Clear cell tumors of bone

Except for clear cell carcinomas that metastasize to bone, with renal cell carcinoma being the principal representative of that group, clear cell osseous neoplasms are rare. The only distinct nosologic entity in this category that is primary in the bone is the clear cell chondrosarcoma (CCCS). This lesion, which is most often seen in the proximal femur or humerus, affects males more often than females and has a peak incidence during the third and fourth decades of life. Radiologic images of CCCS show a well-circumscribed, often calcified lytic lesion that may expand the bone, but only uncommonly breaches the cortex. Clear cell elements in CCCS are accompanied by "conventional" foci of chondrosarcoma in less than 50% of cases; noncartilaginous "secondary features," including areas of osteogenesis, osteoclast-like giant cells, and zones resembling aneurysmal bone cyst or giant cell tumor of bone, may be apparent as well. CCCS is a relatively indolent malignancy; roughly 25% of patients experience local recurrences of their tumors or suffer metastasis, but tumor-related death is uncommon, particularly when the lesion has been completely resected en bloc. Sporadic examples of other tumors in bone also may be focally or entirely composed of clear cells. These include osteosarcoma, chondroblastoma, chordoma, adamantinoma, Ewing's sarcoma, and primitive neuroectodermal tumor. The last two of these lesions represent the most common primary clear cell bone tumors in children, whereas metastatic renal clear cell sarcoma is the most frequent metastatic pediatric tumor in this category.     

The dominant T cell clone is present in multiple regressing skin lesions and associated T cell lymphomas of patients with lymphomatoid papulosis

This study was undertaken to determine the clonality of lymphomatoid papulosis (LyP), its clonal relationship to lymphomas, which occur at high frequency in LyP patients, and to define the cell lineage of Reed-Sternberg-like cells in type A lesions of LyP. Punch biopsies of skin of 11 adult patients with LyP were analyzed for morphologic subtype of LyP, surface antigens, and clonal T-cell receptor (TCR) gene rearrangements. Clonal rearrangements were identified by semiquantitative polymerase chain reaction amplification and sequencing of TCR-beta chain genes in nine patients and TCR-gamma chain genes in two patients. A single dominant clone was detected in multiple separate LyP lesions, often of different histologies, in nine patients. The same clone was detected in LyP lesions and the anaplastic large cell lymphoma (ALCL) of 2 patients and the mycosis fungoides (MF) of 2 other patients. No dominant clone could be detected in one patient with LyP uncomplicated by lymphoma or in a second patient with LyP and MF. A T-cell lineage was evident for RS-like cells in cell culture and in type A lesions. These results show that multiple regressing skin lesions and associated T cell lymphomas (MF and ALCL) are clonally related in most LyP patients, which suggest that the disease in these patients was initiated by a non-random genetic event.     

Clear cell tumors of the alimentary tract and abdominal cavity

In a population of male workers in two ship maintenance companies (n = 32), a workplace survey was conducted in order to quantify their physical load. Postural load was measured by using the Ovako Working posture Analyzing System. During 7480 observations, working postures, exertion of force and working activities were recorded. Awkward postures of the back occurred in 38% of the worktime, stress on the neck/shoulder region due to one or both arms above shoulder level was present in 25% of the worktime. Forceful exertions during lifting, pushing and pulling activities sometimes exceeded published guidelines for manual material handling. Determinants of physical load could be identified and a hazard evaluation procedure was designed by applying rating schemes to weight various patterns of physical load. Ship maintenance work compared well with other strenuous occupations. Considering the high prevalence of back pain (80%) and neck/shoulder pain (60%), as well as the results of the observation method ergonomic improvements are warranted. Physical load can be reduced by several technical adaptations and applications, and by enlarging task rotation.     

White fibrous papulosis of the neck

Since its introduction, fluorescein angiography has been widely used to investigate diseases of the ocular fundus. A case of fatal acute myocardial infarction after intravenous fluorescein angiography is presented. This appears to be the first case documented by autopsy in which the findings are compatible with myocardial infarction as the cause of death. Although there are no known contraindications for fluorescein angiography in patients with a history of cardiovascular disease, the indications for this elective procedure should be carefully reviewed in such patients. Adequate emergency resuscitation equipment should be available in the fluorescein angiography suite.     

Clear cell neoplasms of the urinary tract and male reproductive system

Herein is a review of clear cell neoplasms of selected sites in the urinary tract and male reproductive system, including the kidney, the urinary bladder, testis, epididymis, and prostate. Clear cell cytoplasmic alteration in neoplasms at these sites is a relatively common light microscopic finding. Examples of such neoplasms with clear cell change include the clear cell type of renal cell carcinoma, clear cell adenocarcinoma of urethra and bladder, the classic type of seminoma, papillary cystadenoma of the epididymis, and well-differentiated adenocarcinoma of the prostate. Of importance, numerous non-neoplastic benign entities may also manifest cleared cytoplasm and therefore are presented in the differential in this review. Indeed, knowledge of the neoplastic and non-neoplastic entities displaying clear cell change at each anatomic site should enable the surgical pathologist to approach the differential diagnosis of these conditions in a more logical and rigorous fashion.     

Clear cell mammary malignant myoepithelioma with abundant glycogens

Malignant myoepithelioma (myoepithelial carcinoma) of the breast is extremely rare. A case is reported of a 46 year old female with clear cell mammary malignant myoepithelioma that, on histological examination, was glycogen abundant clear cell carcinoma. Immunohistochemically, the clear cells showed myoepithelial differentiation--that is, they were a smooth muscle actin and S100 protein positive. This case shows that glycogen abundant clear cell carcinoma is a variant of malignant myoepithelioma of the breast.     

Clear cell odontogenic carcinoma with lymph node metastasis

Clear cell odontogenic tumors are rare. Review of the literature showed 9 cases with a prominent clear cell component. These lesions have exhibited an aggressive behavior characterized by an infiltrative local growth pattern, recurrence, or metastases. We report a case of an odontogenic tumor that exhibited a biphasic pattern and was characterized by lymph node involvement identical histologically to the primary tumor. We conclude that the presence of a clear cell component in an ameloblastomatous tumor should be viewed as a sign of de-differentiation, and that a malignancy with or without metastases should be considered and ruled out in such cases.     

Langerhans cell histiocytosis of the skin

Cutaneous involvement in Langerhans cell histiocytosis (LCH) occurs in 50% of cases and may be the presenting feature. It is, therefore, important to recognize the wide spectrum of clinical disease that this disorder may adopt in the skin. Cutaneous involvement is not necessarily a benign feature and many patients progress to multi-system disease. There are a number of treatments available for cutaneous LCH. The rationale is to start with the simplest treatment and progress to systemic or interventional therapy as needed.     

Merkel cell carcinoma of the skin

Primary neuroendocrine carcinoma of the skin or Merkel cell carcinoma is an aggressive primary neoplasm. It is commonly seen in the elderly, on the head, neck and extremities, where it can mimic a benign or less malignant skin tumour. Pathological examination shows a generally dense growth of small dark cells, with immunohistochemical evidence of neuroendocrine differentiation. The microscopic appearance is very similar to metastatic oat cell carcinoma from the lung and this must be excluded by clinical means and appropriate imaging studies. In this study we present 13 new cases of Merkel cell carcinoma (the largest published series in the UK) and summarize 214 cases from the literature in which the survival data are given. In our series, 5 of 13 patients died from spread of the Merkel cell carcinoma. From this and other studies, it appears that early diagnosis and wide local excision may be the only way to prolong survival. No other adjuvant therapy has proved effective.     

Clear cell sarcoma of kidney with tumor extension into the right atrium

A 28-year-old man with a Wilms tumor extending into his right atrium was successfully treated using cardiopulmonary bypass. Histologic examination revealed clear cell sarcoma with invasion of the inferior vena cava. This case represents the oldest patient with clear cell sarcoma of the kidney ever published in the English literature.     

Clear cell sarcoma of the kidney relapsing after 10 years of asymptomatic evolution

In normal pregnancy, end-diastolic flow appears in the umbilical artery around the 13th week of gestation, with a velocity which increases progressively with advancing gestation. The detection of reversed flow in the umbilical artery, the highest expression of an increase in placental vascular resistance, is extremely uncommon in the first half of gestation and, in three of the four cases reported in the literature, there were chromosomal abnormalities. We report a new case of reversed end-diastolic flow in the umbilical artery in a 13-week fetus with increased nuchal translucency thickness, megacystis and tachycardia. Cytogenetic analysis of chorionic villi and amniocytes revealed trisomy 13. The findings provide further evidence for a possible association between reversed end-diastolic flow in the umbilical artery and chromosomal abnormalities. However, the effectiveness of this potential marker in an unselected population requires further evaluation.     

Clear cell adenocarcinoma of the uterine cervix: a histological and histochemical study

A case of Mullerian clear cell adenocarcinoma of the uterine cervix occurring in a young women is presented. A detailed histological and histochemical study of this type of tumour is important so as to separate it from the clear cell tumour of mesoenphric origin. The association of Mullerian clear cell adenocarcinoma and other abnormalities of the vagina and cervix with the administration of maternal nonsteroidal oestrogens has been recently stressed in the literature. However, our patient is illustrative of the 30-50% of cases reported to date which have few if any of the associated abnormalities of the genital tract and have no known exposure to non-steroidal oestrogens.     

Clear cell renal carcinoma metastatic to the thyroid. A case report

A case of clear cell renal carcinoma metastatic to the thyroid 5 years after surgical removal of the primary tumor is presented. The differential diagnosis related to cyto-histologic findings, the uncommon occurrence and the unpredictable behaviour of clear cell renal carcinoma are discussed.     

Clear cell sarcoma: an extremely rare cause of pleural disease

We present the case of a 36 yr old woman with a persisting complaints of left chest pain. A chest radiograph revealed multiple left pleural thickenings. Classical exploration was negative. Thoracic surgery allowed the subtotal removal of a huge pleural tumour. The histological examination revealed a clear cell sarcoma. The literature on this extremely rare tumour is reviewed.     

Clear cell odontogenic tumor in the mandible: report of a case with an immunohistochemical study of epithelial cell markers

A rare case of clear cell odontogenic tumor is presented with an immunohistochemical study using epithelial cell markers. A 35-year-old Japanese man was admitted with a complaint of painless swelling in the anterior region of his mandible. Radiological examination showed a relatively well-defined multilocular radiolucency with root resorption of the adjacent teeth. Despite a subtotal mandibulectomy, the tumor recurred three times. Histologically, the tumor was composed of proliferating clear cells and infiltrated through the cancellous bone. Histochemical and ultrastructural analyses detected cytoplasmic glycogen granules in the clear cells. They showed immunoreactivities for cytokeratin 8, 13 and 19, filaggrin and anti-ameloblastoma antibodies, suggesting an odontogenic epithelial origin.