Solitary fibrous tumor of the nasal cavity and orbit

Solitary fibrous tumors (SFT) are rare spindle cell neoplasms generally associated with the serosal surface, especially the pleura. Two SFT are reported arising in the nasal cavity and orbit, occurring in a 33 year old female and a 21 year old male, respectively. The lesions lacked the characteristic features of other recognized neoplasms that occur in these regions. Immunohistochemically, the tumors cells were diffusely and strongly positive for vimentin and CD34 and some or many tumor cells expressed neuron-specific enolase and Leu-7. Ultrastructurally, the tumor cells showed no distinct features although they were suggested to be primitive mesenchymal or fibroblast-like cells. Both tumors were diploid by flow cytometry. The two patients have had benign clinical courses with limited follow-up. Our findings suggest that SFT is of mesenchymal cell origin and support another location for SFT, indicating additional evidence against mesothelial origin. SFT should be included in the differential diagnosis of spindle cell tumors arising in the nasal cavity and orbit.     

Fine needle aspiration cytology of orbital masses

OBJECTIVE: To review our experience with fine needle aspiration of orbital lesions. STUDY DESIGN: Over an eight-year period, 24 orbital fine needle aspiration (FNA) samples were recorded, 22 of them adequate for interpretation. RESULTS: There were two benign tumors. There were 14 malignant tumors, 5 primary, 8 metastatic and 1 malignant and originating in the nasal cavity, invading the orbit. In two cases the original tissue diagnosis was incorrect and was revised by the fine needle aspirate. There were six nonneoplastic cases. In one case an infectious agent was identified, and another showed atypical lymphoid cells. Of the two nondiagnostic cases, one was compatible clinically with an orbital pseudotumor, and the other had no available follow-up. A specific diagnosis was achieved in 18 of 24 instances, or 75% of the cases. CONCLUSION: FNA is useful in the workup of an orbital lesion, leading to prompt diagnosis and treatment.     

The lesions of the pterygopalatine and infratemporal spaces: Computed tomography evaluation

OBJECTIVE: The purpose of this study was to categorize the computed tomography features of lesions affecting the pterygopalatine fossa and infratemporal fossa and thus aid in the diagnosis of these lesions. DESIGN: Eighty-six patients with lesions of the pterygopalatine fossa and infratemporal fossa were examined with computed tomography; the lesions were confirmed by both surgery and biopsy. The patients were divided into three groups: group I consisted of patients in whom the lesions had originated in one or both fossae; group II, of patients in whom the lesions originated in other oral and maxillofacial regions but showed extension into the pterygopalatine and infratemporal fossae; and group III, of patients in whom the lesions had multicentric origins. RESULTS: Of the 11 cases in group I, demarcation was confined to both fossae in 4 patients, and involvement of the adjacent structures was shown on computed tomography images in 7 patients. Involved structures included the maxillary sinus (4 sides), nasal cavity (3 sides), mandibular ramus (6 sides), buccal space (2 sides), base of the skull (5 sides), palate (3 sides), and parapharyngeal space (5 sides). In the 70 cases in group II, computed tomography images showed that lesions had invaded both fossae via following routes: (1) 40 lesions in the maxillary sinus had infiltrated posterolaterally into 26 pterygopalatine and 39 infratemporal fossae; (2) two nasal cavity and three nasopharynx tumors had infiltrated laterally or lateroanteriorly into five pterygopalatine and one infratemporal fossae; (3) lesions originating in mandibular rami (9 lesions), buccal regions (4 lesions), parapharyngeal spaces (1 lesion) and parotid glands (1 lesion) had intruded medially into 15 infratemporal fossae; (4) two temporal bone tumors had encroached inferiorly on two infratemporal fossae; (5) four palate tumors had led to involvement of three pterygopalatine and four infratemporal fossae; and (6) four inflammatory diseases of the facial spaces involved two pterygopalatine and four infratemporal fossae. Group III lesions (5 cases) affecting one pterygopalatine and five infratemporal fossae were hemangiomas; one was a malignant lymphoma. CONCLUSION: Group I lesions may involve the adjacent anatomic structures of both pterygopalatine and infratemporal fossae in every direction. Group II lesions that correspond to the various origins of the maxillofacial region have different pathways of infiltration into the pterygopalatine or infratemporal fossae. Computed tomography examination is very important in the evaluation of lesions involving the pterygopalatine and infratemporal fossae.     

Small cell neuroendocrine carcinoma of the nasal cavity and paranasal sinuses

Small cell neuroendocrine carcinomas (SNECs) of the sinonasal tract are extremely uncommon tumors. We reviewed the clinicopathologic features of six cases of this neoplasm. There was no sex preponderance with three females and three males and a mean age at presentation of 51 years (range, 38 to 68). Two patients had disease limited to the nasal cavity, and in four the tumor involved the nasal cavity and maxillary or ethmoid sinuses. Involvement of the orbit was present in two patients. Surgery was the primary treatment. After a mean follow-up of 37 months, one patient died of local disease and liver metastases, four were alive with recurrent or metastatic disease, and one died of unrelated causes. The tumors were composed of sheets, nests, and trabeculae with extensive areas of necrosis and hemorrhage. The individual cells were small to intermediate in size and had scanty cytoplasm. The nuclei were oval or round and hyperchromatic with absent or inconspicuous nucleoli. Nuclear molding and crush artefact were present in five cases. All tumors had a high mitotic rate with frequent abnormal mitotic figures. All cases stained for Cam 5.2, neuron-specific enolase, and chromogranin. Five cases were positive for AE1:AE3, and four for synaptophysin. No case stained for S-100 protein, or neurofilaments. O-13 stained one case. No case contained EBV-RNA. SNECs of the nasal cavity and paranasal sinuses are aggressive tumors with pathological features similar to those of anaplastic small cell carcinomas of the lung. They exhibit morphological and immunophenotypic features different from olfactory neuroblastoma and should be distinguished from this tumor.     

Multiple sebaceous adenomas and internal malignant disease: a case report with chromosomal analysis

A case of multiple sebaceous adenomas associated with internal malignant disease is further documented. Thirteen similar cases reported in the literature are also reviewed. We support the thesis that this association represents a unique syndrome. It can be seen in both sexes and usually is manifested during the fifth and sixth decades. A family history of malignant disease was revealed among seven of the nine cases mentioned. Of the other skin lesions, keratoacanthoma is also frequently seen. The internal malignant tumors most commonly afflict the gastrointestinal tract, especially the large intestine. With proper treatment the internal tumors appear to be of a low degree of malignancy. However, these patients have a propensity to develop muliple visceral tumors and require periodic follow-up. Some patients develop skin tumors prior to the discovery of internal malignant disease, an event that offers some prognostic value. Chromosomal study of the cultured blood lymphocytes by the Giemsa banding technique failed to reveal any abnormality.     

Nasal septal pediculate carcinoma in situ: differential diagnosis

Pediculated lesions of the nasal cavities are relatively common in daily practice, and include inflammatory polyps, benign tumors (papillomas being the most common), malignant tumors, and specific processes, such as polypoid rhinosporidiosis. The authors describe a female patient with a warty, pediculated, and asymptomatic lesion in the nasal septal mucosa. The anatomo-pathological exam showed this to be a "carcinoma in situ". The few bibliographic citations report only an association between the tumor and contact with wood dust, such as oak, ebony and beech. The patient was not exposed to these elements. It is important to emphasize the routine performance of a complete otolaryngological exam for patients seeking out specialists, in order to detect potentially malignant lesions whose early removal would permit a complete cure.     

Retinoid X receptor expression in the normal pituitary and clinically ''non-functioning'' pituitary tumours

Nasal chondromesenchymal hamartoma is the suggested appellation for a tumefactive process of the nasal passages and contiguous paranasal sinuses in seven children with a detectable mass in the nose. With the exception of one patient who was 7 years of age at diagnosis, the others were 3 months of age or less upon recognition of the mass. Two children were diagnosed in the first 2 weeks of life. Imaging studies showed a complex solid and cystic mass or masses filling the nasal cavity and extending into the ethmoid sinuses in most cases. Erosion of the surrounding bone, including the cribriform plate, resulted in an intracranial component in the four cases. Surgical resection was the treatment of choice despite its technical difficulties that often necessitated a combined intranasal and intracranial approach. Residual disease with continued growth in one case was the clinical outcome in two children, and the remaining five patients have not experienced any further difficulties. The piecemeal fragments of tissue disclosed a collage of histologic features, but the basic morphologic elements were well-demarcated nodules of cartilage with some variation in the cellular density and maturation of the chondrocytes, a myxoid to spindle cell stroma, focal osteoclastlike giant cells in the stroma, and erythrocyte-filled spaces resembling those of the aneurysmal bone cyst. Two of the tumors were less polymorphous or complex in their spectrum of histologic features. These nasal masses have similarities to the so-called chest wall hamartoma or mesenchymal hamartoma of the chest wall in terms of the clinical presentation in infancy and the basic cartilaginous character of both entities. There is a degree of presumption in the designation of these nasal and chest wall tumors as hamartomas because the pathogenesis has not been established for either entity.     

Primary germ cell tumors of the mediastinum: I. Analysis of 322 cases with special emphasis on teratomatous lesions and a proposal for histopathologic classification and clinical staging

BACKGROUND: Primary germ cell tumors of the mediastinum are unusual neoplasms with histopathologic features that are similar to those of germ cell tumors in the gonads. However, their clinical features, behavior, and spectrum of pathologic features in the mediastinum have not yet been fully defined. METHODS: The clinical and pathologic features of 322 cases of primary mediastinal germ cell tumors were reviewed, with special emphasis on teratomatous lesions. The tumors were divided into groups according to their histologic features and correlated with their order of frequency, patient gender and age distribution, and morphologic features. A clinical staging scheme based on the extent and location of the lesions was devised. RESULTS: The overwhelming majority of patients were men (320); only 2 were women (both had teratomatous lesions with additional malignant components). The patients' ages ranged from 1 to 79 years (mean, 40 years). Histologically, all types of germ cell tumors were represented, including 138 teratomas (87 mature teratomas, 6 immature teratomas, and 45 teratomas with additional malignant components); 120 seminomas; 52 nonseminomatous, nonteratomatous germ cell tumors (38 yolk sac tumors, 6 embryonal carcinomas, and 8 choriocarcinomas); and 12 combined germ cell tumors without teratomatous components. The teratomatous lesions with additional malignant components were further separated into subtypes based on the histologic types of their malignant components, i.e., epithelial, mesenchymal, etc. Clinical staging was possible in 242 cases, with 191 cases (79%) in Stage I, 4 cases (1.6%) in Stage II, and 47 cases (19.4%) in Stage III. In each group, the clinical staging correlated well with the clinical outcome for the majority of patients. CONCLUSIONS: The results of this study showed that mediastinal germ cell tumors have demographic and histopathologic distributions similar to those of tumors occurring in the male gonads, with teratomatous and seminomatous lesions being the most common. Among the nonseminomatous germ cell tumors in this study, the yolk sac tumors appeared to occur the most frequently (the ratio of yolk sac tumor occurrence to embryonal carcinoma occurrence was 6.1:1). In addition, the subclassification of teratomas with additional malignant components based on the histologic types of malignancies may lead to more therapy choices for patients. At the same time, the use of a clinical staging scheme may be of value in predicting clinical outcome and planning therapy.     

The origins of the neural crest. Part I: embryonic induction

Nearly 500 long-term rodent carcinogenicity studies carried out by the National Cancer Institute and the National Toxicology Program were examined, and 12 chemicals were identified that produced nasal tumors: allyl glycidol ether, p-cresidine, 1,2-dibromo-3-chloropropane, 1,2-dibromoethane, 2,3-dibromo-1-propanol, dimethylvinyl chloride, 1,4-dioxane, 1,2-epoxybutane, iodinated glycerol, procarbazine, propylene oxide, and 2,6-xylidine. All 12 of these chemicals produced nasal tumors in rats, and 5 also produced nasal tumors in mice. Most of the nasal carcinogens (1) produced tumor increases in both sexes, (2) produced tumors at other sites as well, (3) had significantly reduced survival at doses that were carcinogenic, and (4) were genotoxic. Only 5 of the 12 nasal carcinogens were administered by inhalation. A variety of different types of nasal cavity tumors were produced, and specific tumor rates are given for those chemicals causing multiple tumor types. Increased incidences of nasal neoplasms were often accompanied by suppurative/acute inflammation, epithelial/focal hyperplasia and squamous metaplasia. However, high incidences of these nonneoplastic nasal lesions were also frequently seen in inhalation studies showing no evidence of nasal carcinogenicity, suggesting that in general nasal carcinogenesis is not associated with the magnitude of chronic toxicity observed at this site.     

Ovarian neoplasms in children

OBJECTIVE: To review the clinical presentation, treatment, and outcome in a series of children with ovarian neoplasms. DESIGN: A retrospective review of the medical records in a case series of 29 girls with ovarian neoplasms. The length of follow-up ranged from 6 months to 7 1/2 years and averaged 3.0 years in the girls with malignant tumors. SETTING: The patients were treated at a large referral children's hospital. PATIENTS: Twenty-nine girls with ovarian neoplasms were treated from 1976 to 1992. The average age of the patients was 10 years and ranged from 2 to 16 years. MAIN OUTCOME MEASURES: The principal outcomes examined were mortality and surgical morbidity. RESULTS: The most common presenting symptoms for these ovarian tumors in pediatric patients included chronic abdominal pain, an abdominal mass, or distention. Three girls presented with precocious puberty or hirsutism. In 27 cases, the tumor was a primary ovarian lesion. In two patients, the ovarian mass was the presenting finding for a stage IV non-Hodgkin's lymphoma. Seventeen tumors were benign and 12 were malignant. Tumors originating from the germ-cell line predominated (n = 17). Seven of the 10 ovarian malignant neoplasms were stage I at the time of diagnosis. All but one of the girls with malignant tumors received either adjunctive radiation therapy or multiple-agent chemotherapy. Two girls with sex cord/stromal cell tumors who presented with stage I disease ultimately developed widespread metastases. Both girls with large epithelial tumors survived. All of the girls with benign tumors and seven (70%) of 10 with malignant lesions survived. CONCLUSION: Ovarian tumors are unusual lesions in the pediatric population. Unlike in adults, such neoplasms generally originate from the germ-cell line. Whereas most ovarian tumors in girls are benign, some children have malignant tumors that are very aggressive and do not respond well to adjuvant therapy. In particular, malignant sex cord/stromal cell tumors, even when they present at an early stage, may behave unpredictably.     

Invasive squamous cell carcinoma arising from asymptomatic choristomatous cysts of the orbit. Two cases and a review of the literature

BACKGROUND: Epithelial choristomatous cysts are common orbital lesions, the most frequent of which are dermoid or epidermoid tumors. Massive enlargement or extraorbital extension of these benign lesions may occur. Malignant transformation of the epithelial lining of epidermoid cysts is rarely reported. METHODS: Two patients are presented in whom the epithelial lining of a previously asymptomatic choristomatous cyst of the orbit underwent malignant transformation to produce invasive squamous cell carcinoma. The unusual origin and clinical presentation of the lesions caused a delay in the diagnosis and therapy in both patients. Metastatic workup was negative in both patients, who underwent resection of their tumors via orbital exenteration with craniofacial resection. Reported cases of malignant transformation in analogous choristomatous cysts elsewhere in the cranium are reviewed. RESULTS: One patient is alive and well without recurrent disease 40 months postoperatively. The second patient died of a pulmonary embolus 2 months postoperatively. Autopsy showed no residual tumor. Overall, only 3 of 18 reported patients with epidermoid choristoma of the head and orbit with malignant transformation were alive when reported. CONCLUSIONS: Malignant squamous metaplasia is believed to be a rare complication of orbital dermoid or epidermoid cysts, with only two previously reported cases. However, malignant transformation is relatively frequent in analogous epidermoid cysts found elsewhere in the cranial vault, especially after incomplete excision. These reports encourage the complete removal of epithelial choristomas of the orbit.     

Molecular analysis reveals a high mutation frequency in the first untranslated exon of the PPOX gene and largely excludes variegate porphyria in a subset of clinically affected Afrikaner families

Primary mediastinal ependymomas are unusual tumors, with only two case reports previously reported in the literature. In this study, we review our experience with three cases of primary mediastinal ependymomas, including the clinical, histopathologic, immunohistochemical, and ultrastructural features. The three patients in this study were white women with a mean age of 50 years (age range, 36 to 71 years). Presenting symptoms were nonspecific; radiographically, all lesions were circumscribed posterior mediastinal masses without evidence of bone involvement. There was no evidence of central nervous system, sacral, or pelvic ependymoma. All tumors were completely resected, ranged in size from 5 to 7 cm (mean, 6 cm), and exhibited glistening pseudocapsules. Two tumors had a solid, tan-gray cut surface and one lesion was cystic with a mural tumor nodule. All neoplasms showed histologic features of conventional cellular ependymomas with perivascular pseudorosettes and occasional true ependymal rosettes. Germ cell components were not present in any case and immunohistochemical analysis showed glial fibrillary acidic protein, S-100, and patchy cytokeratin immunoreactivity in all three cases as well as absence of reactivity for HMB 45, chromogranin, and synaptophysin. Ultrastructural features included multipart "zipper-like" junctions, intracytoplasmic lumina containing microvilli, occasional cytoplasmic basal bodies, and apical cilia. A microscopic metastasis was present in a regional lymph node in one case at the time of resection; however, there is no evidence of recurrence or distant metastasis in any of the cases during the postoperative period (mean length of follow-up, 64 months). Ependymomas rarely occur in the mediastinum and have a predilection for the posterior mediastinum. The paravertebral location, microscopic identification of adjacent sympathetic ganglia, and lack of teratomatous or other germ cell components suggest that mediastinal ependymomas are likely derived from paravertebral ependymal rests. Primary mediastinal ependymomas are characterized by a prolonged and indolent clinical course. Metastasis to regional lymph nodes may occur, but distant metastases are unusual in our experience. Complete surgical excision seems to offer the best chance for long-term survival.     

Low-grade myofibroblastic sarcoma: analysis of 18 cases in the spectrum of myofibroblastic tumors

The clinicopathologic, immunohistochemical, and ultrastructural features of a seemingly distinctive low-grade spindle cell sarcoma showing myofibroblastic differentiation have been analyzed in a series of 18 patients. The age range of the patients (7 women and 11 men) was 19-72 years (median: 42 years). A painless, enlarging mass was the most common clinical presentation. Five tumors arose in the oral cavity (including four lesions in the tongue), four in the lower extremities and three in the upper extremities, four cases in the abdominal/pelvic cavity, and two on the trunk. Eight soft-tissue cases involved skeletal muscle, three cases were located in perifascial tissues, and two arose in subcutaneous tissue. Tumor size ranged from 1.4 to 17 cm (median: 4 cm); in six cases (of which four were abdominal/pelvic) the lesion was larger than 5 cm. All patients were treated surgically, and four received additional adjunctive therapy. Histologically, most cases were cellular lesions showing a diffusely infiltrative pattern, and were composed of spindle-shaped tumor cells arranged mainly in fascicles. Tumor cells had poorly defined, palely eosinophilic cytoplasm and fusiform nuclei, which were either tapering and wavy or plumper and vesicular with indentations and small inconspicuous nucleoli. Tumor cells were set in a collagenous matrix often with prominent hyalinization. Mild nuclear atypia was noted in 16 cases; in the other 2 cases, and in the metastases of one other lesion, a greater degree of nuclear atypia was seen. In all but one case, the mitotic rate ranged from 1 to 6 mitoses in 10 HPFs (mean: 2/10 HPFs); in a single case, there were more than 20 mitoses in 10 HPFs. Immunohistochemically, all cases stained positively for at least one myogenic marker; 12 cases were positive for desmin, 11 for alpha-smooth muscle actin, and 6 for muscle actin (HHF35). Seven neoplasms were desmin positive/ alpha-smooth-muscle actin negative, and five cases were desmin negative/alpha-smooth-muscle actin positive emphasizing the variable immunophenotype of myofibroblastic lesions. In addition, 7 of 10 tumors stained at least focally positive for fibronectin. Ultrastructural examination in five cases showed characteristic features of myofibroblasts. Follow-up in 11 patients (median: 29 months) revealed local recurrence in 2 cases, and multiple distant soft-tissue, intraosseous, and pulmonary metastases in one other patient. Low-grade myofibroblastic sarcoma seems to represent a distinct entity in the spectrum of low-grade myofibroblastic neoplasms and is distinguishable from fibromatosis, myofibromatosis, solitary fibrous tumor, fibrosarcoma, and leiomyosarcoma.     

Mathematics preparation and professional development of deaf education teachers

Tumors of the nasal fossa and paranasal region are uncommon and have non-specific initial clinical features. This complicates the diagnosis and delays treatment. We reviewed all our cases of nasal sinus tumors (84 benign, 50 malignant and 15 moderately malignant) and the relevant literature. This data was use to develop a protocol for classifying the symptoms, clinical and radiological features, coded diagnosis, and the most suitable treatment and follow-up.     

Chordomas of the mediastinum: clinicopathologic, immunohistochemical, and ultrastructural study of six cases presenting as posterior mediastinal masses

Six cases of chordomas presenting as primary posterior mediastinal tumors are described. Three patients were female, and three were male between the ages of 8 and 65 years (mean, 40.6 years). In all cases, the tumors presented radiographically as relatively well-circumscribed, encapsulated soft tissue masses that did not seem to be related to the thoracic or dorsal spine. Only in one case, focal infiltration of bone at the level of T6-T7 was observed at the time of surgery. Histologically, the lesions showed a spectrum of features that ranged from sheets and cords of large cells with abundant vacuolated cytoplasm to small, stellate cells embedded within an abundant mucoid matrix. In one case, the cell population showed more pronounced nuclear atypia with loss of cytoplasmic vacuolization, frequent mitotic figures, necrosis, and solid areas characterized by a perivascular distribution of atypical spindle cells set against a myxoid stroma. Another case showed features of chondroid chordoma, with an immature chondroid-appearing matrix surrounding the atypical tumor cells. Immunohistochemical studies in all cases showed positive staining of the tumor cells with CAM 5.2 and broad-spectrum keratin, epithelial membrane antigen (EMA) and vimentin, and, to a lesser extent, with S-100 protein. Stains for muscle actin, carcinoembryonic antigen (CEA), and desmin were negative. Ultrastructural examination in two cases showed a spectrum of features that varied from large cells with abundant cytoplasm containing scattered ribosomes, glycogen granules, Golgi apparatti, abundant intermediate filaments, and small lumen formation with immature microvilli to smaller cells with elongated cytoplasmic processes, fewer intermediate filaments, rare desmosome type intercellular junctions, and complexes of mitochondria/rough endoplasmic reticulum. On clinical follow-up, two patients died with metastases to the lungs, chest wall, and liver from 1 to 3 years after diagnosis, and two patients are alive and well without evidence of disease after 3 and 16 years. Chordoma should be entertained in the differential diagnosis of posterior mediastinal tumors. Application of immunohistochemical stains or electron microscopy will be of aid in separating them from other conditions that may histologically closely resemble these lesions.     

Non-Hodgkin lymphoma of the central skull base: MR manifestations

OBJECTIVE: The aim of this study was to demonstrate the MR characteristics of non-Hodgkin lymphoma of the skull base to help in the differential diagnosis of this neoplasm from other conditions. MATERIALS AND METHODS: MR of five patients, 7-64 years old, with pathologically proved lymphomas of the skull base were reviewed. Three cases had primary skull base lesions involving the sphenoid bone and the cavernous sinus. One case with a nasal cavity lesion involving the skull base and one with a relapsing skull base lesion of previously treated tonsillar lymphoma were included. RESULTS: The lesions had signal intensities that were similar to that of gray matter of brain on both T1- and T2-weighted imaging. Bilateral cavernous sinuses were involved with encasement of internal carotid arteries in every case. Postcontrast MR showed homogeneous enhancement of the tumor with dural infiltration along the planum sphenoidale, clivus, or tentorium. The clivus was destroyed or replaced by tumors in adult cases but in two children the clivus was preserved with intact sphenooccipital synchondrosis. In one case the tumor extended to the extracranial portion through the jugular foramen. CONCLUSION: The MR findings of a permeative lesion of the skull base, invasion of the cavernous sinus without arterial narrowing, infiltration along the dural surface, and an iso- or hypointensity with brain on T2-weighted imaging should suggest lymphoma.     

Unilateral lobectomy for Hurthle cell adenoma

Considerable controversy exists regarding the ability to predict the biologic behavior of Hurthle cell tumors. Some have found the clinicopathologic criteria used to differentiate benign from malignant lesions to be unreliable and have advocated total thyroidectomy for all Hurthle cell neoplasms. From January 1980 to December 1995, 39 patients had surgery for Hurthle cell tumors of the thyroid. The surgical pathologic findings were reviewed by an experienced pathologist (JP). Eight patients had histologic findings of capsular or vascular invasion consistent with carcinoma and had total thyroidectomy. Four of these patients had postoperative evidence of residual disease and were treated by radiation ablation. No evidence of invasion was found in 31 patients diagnosed with Hurthle cell adenoma. Twenty-three of these patients had unilateral lobectomy; total thyroidectomy was done in the remaining 8 patients, 5 of whom were found to have an associated papillary carcinoma at the time of operation. There were no operative deaths or significant morbidity. Twenty-two adenomas (71%) were found in females, whereas males had malignant tumors in 6 of 8 cases (P = 0.025). The mean age of adenoma patients is 54.1 years, and that of the carcinoma patients is 55.8 years. Mean size of benign tumors was 2.8 cm and of malignant tumors 4.1 cm (P = 0.04). Four of seven (57%) carcinomas were larger than 4 cm as compared with 6 of 30 (20%) adenomas (P = 0.069). Follow-up has ranged from 1 month to 15 years, with a mean of 3.2 years. There have been no deaths, and no patients with Hurthle cell adenoma have had evidence of recurrence or metastases during follow-up. Our data suggest that carcinoma patients tend to be male and tumor size is larger. An association was found when trying to predict malignancy by using 4 cm as a threshold size. We conclude that pathologic evidence of capsular or angioinvasion can accurately differentiate benign from malignant tumors. Unilateral thyroid lobectomy is adequate therapy for the treatment of Hurthle cell adenoma, with total thyroidectomy reserved for those patients with histologically proven carcinoma.     

Xenopus laevis fertilisation: analysis of sperm motility in egg jelly using video light microscopy

OBJECTIVE: To evaluate the origin of pseudomyxoma peritonei (PMP) in Chinese women. METHODS: The clinicopathologic features of 15 cases of PMP were reviewed. Immunostaining using antibodies for CK7 and CK20 was performed in the ovarian, appendiceal and peritoneal lesions of these cases. RESULTS: Appendiceal pathology was documented in five cases, including four mucinous cystadenoma and one simple mucocele. Eight ovarian tumors were found, including seven mucinous cystadenocarcinomas of low malignant potential and one mucinous cystadenoma. Synchronous ovarian and appendiceal lesions were discovered in three cases. One patient had adenocarcinoma of the pancreas. The origin of mucin production was not known in four cases with metastatic adenocarcinoma found in two of them. Immunoreactivity for CK20 was demonstrated in the tissues derived from the peritoneum, ovary, appendix and pancreas while only 23% (3 out of 13 women) of the peritoneal lesions and 33% (2 out of 6 women) of the ovarian tumors were immunoreactive for CK7. CONCLUSIONS: PMP is a heterogeneous lesion, which may develop from mucinous metaplasia of the peritoneum or from appendiceal, or ovarian lesions. Careful examination of the ovary and appendix with performance of appendectomy is advised in every case of PMP. Immunohistochemical examination of the peritoneal, ovarian or appendiceal lesions using antibodies, in particular that for CK7 would help in defining the origin of mucin production.     

Regional epidemiological features of lip, oral cavity, and oropharyngeal cancer

Lip, oral cavity, and oropharyngeal cancer are among the most common forms of the disease in the world. These types of cancer display significant geographic, ethnic, and socioeconomic variations. We examined the cases of cancer of the lip, oral cavity, and oropharynx diagnosed in the Department of Otolaryngology at the University of Uluda? School of Medicine during the last 5 years, July 1990 to June 1995, and recorded the epidemiological features of these tumors. The Department of Otolaryngology treated a total of 26,225 in- and outpatients during the 5-year period. 320 of these patients (1.2%) were seen for head and neck cancer. 42 of the 320 patients (13.1%) were diagnosed with cancer of the lip, oral cavity, and oropharrynx. After the larynx, this was the second most frequent location of malignant head and neck tumors. We discovered the following epidemiological and pathological features: (1) The incident rate was highest in patients between 41 and 60 years of age. (2) 70% of the patients were male, and 76% of them had a history of tobacco/alcohol use. (3) Occupation had no apparent relevance (four of the patients were farmers). (4) Approximately one third of the patients had undergone medical therapy prior to diagnosis. (5) One third of the patients had initially seen a dentist for treatment, and approximately half had poor dental and oral hygiene. (6) The most frequent symptom was ulceration. (7) Histopathological examination revealed squamous cell carcinoma in 88% of the cases. (8) The cancer was localized to the lip in 31% of cases, oral cavity, 50%, and oropharynx, 19%. (9) Almost half of the cancer cases were diagnosed in advanced stage (stages III and IV).     

Spindle cell malignant lymphoepithelial lesion of the parotid gland: clinical, light microscopic, ultrastructural, and in situ hybridization findings in one case

Malignant lymphoepithelial lesions (MLEL) are rare tumors of the salivary glands that show high incidence in Inuit Canadians, Alaskans, and Greenland Eskimos. The tumors are usually anaplastic or poorly differentiated squamous cell carcinomas. Focal spindle cell elements have been rarely reported. The tumors have been epidemiologically linked to Epstein-Barr virus infection. We present a case of malignant lymphoepithelial lesion showing exclusive spindle cell morphology. The patient is a 44-year-old male Inuit Canadian who presented with a long-standing history of a left parotid mass. The mass did not show evidence of rapid growth or facial nerve involvement. Parotidectomy was performed. The tumor was histologically composed of spindle cells nodules in a background of lymphocytes. The spindle cells showed no evidence of cytologic atypia but were mitotically active. Immunohistochemical staining for low-molecular-weight cytokeratin was only focally positive. The differential diagnosis included a mesenchymal neoplasm and malignant lymphoepithelial lesion. Electron microscopic examination confirmed the squamous nature of the neoplasm. Intracytoplasmic viral particles were also identified ultrastructurally. In situ hybridization for Epstein-Barr virus mRNA using a 30-base oligonucleotide probe specific for the EBER-1 gene showed very high level of expression in the tumor cells. No expression was noted in the adjacent parotid gland tissue. Our findings confirm the squamous nature of malignant lymphoepithelial lesions despite the spindle cell morphology occasionally seen in these neoplasms. They also confirm the strong role of Epstein-Barr virus infection in the pathogenesis of these tumors. This may have further diagnostic and therapeutic implications.(ABSTRACT TRUNCATED AT 250 WORDS)