A phase II trial of weekly infusional 5-fluorouracil in combination with low-dose leucovorin in patients with advanced colorectal cancer

We examined 59 breast cancers for p53 and bcl-2 protein expression by immunohistochemistry. The results were correlated with Ki-67 immunostaining. p53-negativity was noted in 40 cases and the remaining 19 tumours were p53-positive. Thirty-six tumours showed strong expression of bcl-2 and in 23 no staining for this protein was observed. We found statistically significant reverse correlation between expression of p53 and bcl-2 in majority of carcinomas: 31 cases were bcl-2 positive and p53-negative, and 14 tumours were bcl-2-negative and p53-positive. Six carcinomas showed no nuclear staining for Ki-67 and in the remaining 53 the percent of cancer cells positive for Ki-67 ranged from 1 to 60 (mean: 14.6). In these 53 cases we found that bcl-2-positive tumours were characterized by lower proliferation than bcl-2-negative tumours, the mean value of Ki-67 immunostaining being 10.7% and 23.0%, respectively. p53-negative tumours showed lower proliferation than p53-positive tumours: mean Ki-67 index was 10.2% and 23.9%, respectively. We conclude that immunohistochemically detected p53 and bcl-2 proteins show a significant inverse relationship in majority of breast carcinomas and their expression correlates with tumour proliferation (Ki-67 immunostaining).     

Immunohistologic analysis of gastrointestinal and pulmonary carcinoid tumors

Carcinoid tumors are potentially malignant neoplasms that arise in various body sites, including the lung and gastrointestinal tract. Those that appear cytologically atypical are more likely to behave aggressively than more typical carcinoid tumors. However, in the absence of cytological atypia or large tumor size, it is difficult to predict the biology of an individual tumor, because some lesions metastasize, whereas others do not. This study had four aims: (1) To study the expression pattern of p53, Ki-67, NCAM, and S-100 in carcinoid tumors and to relate these expression patterns to classical histopathologic features and to tumor location. (2) To identify nonhistological markers that might more accurately predict the early behavior of carcinoid tumors. (3) To determine whether sustentacular cells are present in carcinoid tumors arising in tissues derived from different embryological derivatives. (4) To determine the synaptophysin and chromogranin immunoreactivity in neuroendocrine tumors arising in various locations. The immunostaining reactions were quantitatively scored by three observers. Only 3 of the 39 tumors (all histologically atypical) were strongly positive for Ki-67; two of these were also strongly p53 immunoreactive. NCAM immunostaining differed according to the site of origin: 76.5% of foregut lesions, 58% of the midgut lesions, and 20% of hindgut lesions were positive. S-100 immunostaining ranged from 41% in foregut lesions to 50% in both the hindgut- and midgut-derived tumors. S-100-positive sustentacular cells were present in 20.5% of carcinoid tumors. All tumors stained with antibodies against synaptophysin. In contrast, 100% of midgut, 60% of hindgut, and 88% of foregut tumors were chromogranin positive. Carcinoid tumors tend to have low proliferative rates. p53 immunostaining tends to be strongly positive in tumors that are histologically atypical, but it is negative in typical carcinoid tumors arising in the gastrointestinal tract and lungs. Immunostaining reactions with antibodies to NCAM, S-100, and chromogranin differ depending on the site of origin. Synaptophysin stains 100% of carcinoid tumors regardless of their site of origin. In contrast, antibodies to chromogranin fail to stain 40% of hindgut tumors and 12% of foregut carcinoid tumors. S-100-positive sustentacular cells are present in foregut and midgut tumors but not in hindgut tumors.     

Mitotic cyclins and cyclin-dependent kinases in melanocytic lesions

Recent evidence has implicated cyclins and cyclin-dependent kinases in the evolution and progression of various malignancies. We studied the immunohistochemical expression of cyclin A, cyclin B, and cyclin-dependent kinase p34cdc2 in a broad spectrum of benign and malignant melanocytic lesions. Formalin-embedded, parrafin-fixed tissue sections from 66 malignant melanomas (MM) and 60 benign nevi were examined for the expression of these cell-cycle proteins. The results were compared with the standard proliferative marker Ki-67 and mitotic index. MM showed significantly higher immunoreactivity for cyclin A, cyclin B, p34cdc2, and Ki-67 compared with benign nevi. Cyclin A, p34cdc2, and Ki-67 displayed strong co-expression in MM. Overexpression of cyclin A and p34cdc2 correlated with histological type, mitotic activity, Ki-67 index, tumor thickness, Clark's level, and clinical outcome in MM. In invasive MM, increased immunostaining of cyclin A and Ki-67 were associated with decreased patient survival. These findings indicate potential roles of mitotic cyclins and cyclin-dependent kinases in the pathogenesis and progression of malignant melanoma.     

Malignant peripheral nerve sheath tumors: the St. Jude Children's Research Hospital experience

BACKGROUND: Malignant peripheral nerve sheath tumors (MPNSTs) are uncommon in young patients. To contribute to the understanding of these tumors, we reviewed the records of all patients treated for PNSTs at one institution over a 30-year period. METHODS: We reviewed the records of eight patients treated for benign PNSTs and 28 patients treated for 29 MPNSTs. We focused on the latter group, statistically testing several clinical factors for their significance in affecting survival. RESULTS: Five-year survival in patients with MPNSTs was 39%. The most significant prognostic factor was gross tumor resectability (p = 0.0004). Five-year survival for patients with resectable tumors was 65%, whereas no patient with unresectable disease survived > 25 months. Tumor grade, site, and patient race were also significant factors by univariate analysis but were not significant when adjusted for resectability. CONCLUSION: Gross tumor resection is crucial in treating malignant PNSTs. Supplemental radiation therapy is recommended for positive microscopic margins. More effective treatment is still being sought for unresectable disease.     

Membrane type 1-matrix metalloproteinase is involved in the formation of hepatocyte growth factor/scatter factor-induced branching tubules in madin-darby canine kidney epithelial cells

The cyclin-dependent kinase inhibitor p27 is a negative regulator of the cell cycle and a potential tumor suppressor gene. Because we had previously demonstrated that loss of p27 protein is associated with aggressive behavior in colorectal adenocarcinomas, we used immunohistochemistry and in situ hybridization to evaluate the potential role of alterations in p27 expression in primary and metastatic colorectal adenocarcinomas. Parallel immunostaining was performed for Ki-67 and p53. We evaluated 13 cases of metachronous and 23 cases of synchronous primary and metastatic colorectal tumor pairs. In the synchronous subgroup (Stage IV tumors), 57% of the primary tumor and metastases pairs did not express p27 protein and the remainder were low expressors. In the metachronous subgroup, 54% of the primary tumors were low expressors and the remainder high expressors of p27 protein. There was a significant reduction in the expression of p27 in the metachronous metastases (mean positive cells: 14.5%) when compared to the corresponding primary tumors (mean positive cells: 41.8%), P = 0.0023. All the primary and metastatic tumors in the metachronous subgroup showed high levels of p27 mRNA expression. There was no association between loss of p27 and either Ki-67 count or p53 expression. Because p27 is known to be up-regulated when epithelial cells are grown in suspension, the down-regulation of p27 in circulating tumor cells may confer the ability to grow in an environment of altered extracellular matrix or intercellular adhesion properties, two situations which may facilitate metastases.     

Hepatocyte growth factor and c-MET in benign and malignant peripheral nerve sheath tumors

Hepatocyte growth factor (HGF), secreted by mesenchymal cells, has pleiotropic biological activities on several cell types. HGF and its receptor, the c-met proto-oncogene product (c-MET) have been implicated in the genesis and progression of several carcinomas and sarcomas. It has been suggested that MET/HGF autocrine signaling may contribute to tumorigenesis in sarcomas. HGF has been recently found to be a mitogen for rat Schwann cells and to be present in neurofibromas in NF1 patients. In this investigation, we assessed the immunoreactive patterns of HGF and MET in benign and malignant peripheral nerve sheath tumors (PNST) using archival formalin-fixed tissue. The standard avidin-biotin-peroxidase method was used. All benign tumors were negative with HGF. Eight cases of MPNST were positive with both HGF and MET. In some malignant PNST, positivity with both ligand and the receptor may be indicative of an autocrine mediated signal transduction and may implicate HGF/MET in tumor progression. Immunoreactivity with MET was strikingly greater in MPNST in contrast to benign PNST; this finding may prove to be helpful in distinguishing some histologically low-grade MPNST from cellular and atypical benign PNST.     

Single cell multiple biomarker analysis in archival breast fine-needle aspiration specimens: quantitative fluorescence image analysis of DNA content, p53, and G-actin as breast cancer biomarkers

Fine-needle aspiration (FNA) is a sensitive and cost-effective method for evaluating breast lesions. However, the diagnosis of early premalignant lesions is less reliable by FNA because of a lack of distinctive cytological features. Accurately defining the risk of such lesions at the individual level may have significant impact in breast cancer prevention and management. The main objective of this preliminary study was to develop a method to study multiple biomarkers on archival FNA slides using quantitative fluorescence image analysis (QFIA). Biomarkers p53, G-actin, and DNA content were labeled with an immunofluorescence technique and measured by QFIA simultaneously on a single cell basis. QFIA allows the labeling and measurement procedures to be carried out in situ, without the need to remove cells from the slide while preserving the morphology of the cells. FNA slides from 72 incident patients were obtained for this study. Fifty-six cases had an adequate number of cells for the actual analysis (25 benign breast lesions, 14 proliferative breast diseases with nuclear atypia, and 17 malignant lesions). The DNA content (> or = 5c) and G-actin (average gray mean, > 90) were positive in 81% and 88% of malignant lesions, respectively. These were significantly higher than the corresponding positive rates in benign lesions (7% and 15%, respectively; P <0.01 for both). None of the benign cases were positive for G-actin and DNA simultaneously, and none of the malignant cases were negative for G-actin and DNA together. p53 was positive in 33% of malignant lesions and 8% of benign lesions (P >0.05). Our study demonstrates the feasibility of evaluating multiple biomarkers by QFIA on archival FNA-fixed specimens. The G-actin and DNA content assayed by QFIA may be potential intermediate end point markers for breast cancer individual risk assessment.     

Impedance of a goat eye lens

Cyclins are essential proteins in cell cycle control, and their deranged expression has been reported to be associated with malignant transformation. Involvement of cyclins in the development of endometrioid carcinomas of the endometrium was studied immunohistochemically using antibodies against both cyclin A and tumor suppressor gene product p53, and their expression was compared with that of Ki-67 antigen. Sixty-two cases of endometrial endometrioid carcinoma and 20 cases of normal endometrium (10 proliferative and 10 secretory phase) were examined. Of the 62 endometrioid carcinomas, atrophic endometrium and hyperplasia were found adjacent to the cancers in 30 and 19 cases respectively. Cyclin A was expressed in < 1% of the glandular cells of normal endometrium in the proliferative phase and in hyperplasia, but was negligible in normal secretory phase and atrophic endometrium. p53 was almost always negative in normal endometrium and hyperplasia. Of the 62 endometrioid carcinomas, 12 tumors (19.4%) overexpressed cyclin A and 21 tumors (33.8%) overexpressed p53 (positive cells > 1%). Cyclin A and p53 were more frequently expressed in poorly differentiated tumors than in well differentiated tumors (cyclin A, p = 0.002; p53, p = 0.016). In addition, cyclin A-positive cells were topographically related to those cells positive for p53 as well as Ki-67. In conclusion, the abnormal expression of cyclin A and p53 is associated with high-grade endometrial endometrioid carcinomas.     

Improved detection of adenocarcinoma of serous fluids with p53 immunocytochemistry

OBJECTIVE: To investigate the potential value of p53 protein immunostaining in identifying malignant cells in serous fluids. STUDY DESIGN: We applied p53 immunostaining to 26 cytologically malignant, 8 suspicious and 34 benign specimens of serous fluids from 68 patients. For comparison, staining for carcinoembryonic antigen (CEA) was also done on all the specimens. RESULTS: CEA was positive in 23 of 26 (88%) cytomorphologically malignant, 3 of 8 (38%) suspicious and 1 of 34 benign cases. p53 Nuclear immunostaining was positive in 12/26 (46%) malignant, 2/8 (26%) suspicious and no benign cases. Correlation between p53 staining and serous fluid type (benign, suspicious or malignant) was significant. The P based on Fisher's exact test was < .0001. Two cases that were reported cytomorphologically as suspicious stained positively with p53; further investigation in those cases confirmed the diagnosis of metastatic adenocarcinoma. CONCLUSION: p53 Immunostaining of serous fluids seems to be of value in identifying carcinoma cells, especially in those cases that show inconclusive or bland cytologic features. Combining p53 with CEA immunostains in clinically or cytologically suspicious cases may assist in recognition of carcinoma cells and in pursuing an appropriate therapeutic approach.     

Differential expression of cell survival and cell cycle regulatory proteins in cutaneous squamoproliferative lesions

Previous models of cutaneous carcinogenesis have primarily focused on the regulation of keratinocyte (KC) proliferation and differentiation. However, it has become clear in many neoplastic systems that altered rates of cell death and/or inability to undergo growth arrest can also contribute to the development of cancer. Apoptosis-regulatory proteins include those that block apoptosis such as Bcl-2 and Bcl-x, whilst a related protein Bax promotes apoptosis. Cell cycle regulatory proteins include those associated with growth arrest, i.e. p21wafl, p53, and those associated with proliferation, i.e. Ki-67. Paraffin embedded samples from ten different lesions of squamous cell carcinoma (SCC), Bowen's disease (BD), keratoacanthomas (KA), and nine normal adult skin samples were stained by immunohistochemistry to detect expression of Bcl-2, Bcl-x, Bax, Ki-67, p21wafl, p53 and apoptosis (TUNEL assay). Compared to low levels of Bcl-x and Bcl-2 immunostaining in normal skin, all the squamoproliferative lesions had strong and diffuse KC expression of Bcl-x (>80%) but minimal to absent KC Bcl-2 expression (<15%). Bax immunopositivity was limited to the basal layer in normal skin and BD. In contrast, by examining serial sections both Bcl-x and Bax appeared to be coexpressed by the majority of malignant KCs in KA and SCC (>70%). These immunostaining profiles reveal that squamoproliferative lesions, including invasive transformed KCs, preferentially express Bcl-x over Bcl-2, in addition to upregulating their Bax levels. Even though there were numerous TUNEL positive cells in these squamoproliferative lesions, no other evidence of apoptosis was seen reinforcing the necessity to use caution when relying on TUNEL staining for identification of programmed cell death in skin biopsies. Normal sun-exposed skin had low but detectable p53 and rare p21wafl KC expression. Significantly higher numbers of p21wafl and p53 immunopositive KCs were noted throughout the lesions in BD and SCC in contrast to KA where p53 and rare p21wafl immunopositive KCs were primarily limited to the periphery of the tumor cell islands. In general, p53 KC expression was higher in all squamoproliferative lesions and sun-exposed normal skin compared to p21Wafl expression. Summary of the expression of cell cycle regulatory proteins for both p21wafl and p53 KC expression was: SCC > BD > KA, in marked contrast to Ki-67 KC expression which was: BD > KA > SCC. The relatively few malignant cells in SCC that were actively participating in the cell cycle (i.e. Ki-67 positive) suggests that these neoplasms may arise primarily by increased cell survival and resistance to apoptosis rather than by hyperproliferation. These studies emphasize the importance of examining multiple members of protein families that regulate apoptosis, proliferation, growth arrest, and differentiation. It is the overall balance between these cellular phenomena that determine whether a cell remains viable or undergoes programmed cell death and contributes to the appearance of a neoplasm. The overexpression of Bcl-x may confer a survival advantage to malignant KCs unable to growth arrest to repair damaged DNA (mutant p53) and/or undergo terminal differentiation (increased p21wafl). Thus, mutation or aberrant expression of such proteins may participate in the multistep process of carcinogenesis that gives rise to these squamoproliferative lesions.     

Postoperative prognostic factors for carcinoma of the thoracic esophagus

To evaluate significant postoperative prognostic factors for esophageal carcinoma, clinicopathological findings and several markers for biological malignant potential were studied, including cell nuclear DNA contents, EGF receptor, p53 protein, MMP-2, Ki-67 positive cell rate, and tumors infiltrating Leu 7 cells. The subjects of this study were 96 patients with thoracic esophageal carcinoma, who underwent radical surgery with extended lymphadenectomy. In the pathological findings, the postoperative survival rate significantly correlated with depth of invasion (pT1(-2) vs. pT3, p = 0.003), lymph node involvement (pNo vs. pN1, p = 0.0002), vascular invasion (-vs. +, p = 0.0003), stage (pSt. 1-2A vs. 3, p = 0.0018), and the number of node involvements (1-3 vs. more than 4, p = 0.025). Analyzing the markers for the malignancy, a significant difference in postoperative mortality due to the relapse was recognized with p value of 0.0009 between Ki-67 positive (under 1%) and Ki-67 negative (over 1%) tumor. Ki-67 positive tumor significantly correlated with the mortality in both cases with pNo (p = 0.024) and pN1 (p = 0.020). Low-grade tumor infiltrating Leu 7 cells significantly correlated with the mortality (Grade 1+ vs. 2+, p = 0.013; Grade 1+ vs. 3+, p = 0.008). These results suggest that Ki-67 study is a useful prognostic factor after radical surgery for thoracic esophageal carcinoma.     

Diagnostic value of an antibody enzyme-linked immunosorbent assay using affinity-purified antigen in an area endemic for melioidosis

Oral squamous cell carcinoma develops through a series of precancerous stages manifested at the microscopic level as epithelial dysplasia. Mutation of the p53 tumour suppressor gene is thought to be an important component of oral carcinogenesis. p53 regulates cell proliferation and DNA repair by inhibiting the cell cycle at G1/S; loss of p53 function may therefore lead to aberrant cell kinetics. To date, no studies have examined the relationship between p53 protein and alterations in cell kinetics in oral epithelial dysplasia from a single anatomical site. Serial sections were studied from 40 routinely processed biopsy specimens of epithelial dysplasia from the floor of the mouth. The expression of p53 protein was determined by immunohistochemistry and cell proliferation was studied by immunostaining for the cell cycle-dependent protein Ki-67. The number of positive cells per millimetre of basement membrane was determined using computer image analysis and compared with site-matched normal controls. The mean p53 labelling index (LI) in normal mucosa was low, 3.48 +/- 0.92 [mean +/- 95 per cent confidence interval (CI)], and increased sharply in the transition from mild (42.49 +/- 21.71) to moderate (104.86 +/- 51.39) epithelial dysplasia. The mean p53 LI for severe dysplasia was 119.09 +/- 56.50. Differences were also observed in the distribution of p53-positive cells between grades of dysplasia, with the development of compact p53-positive foci in severe dysplasia. Mean proliferative indices, as determined by Ki-67 expression, were significantly associated with grade of epithelial dysplasia. Furthermore, there was a significant correlation between p53 LI and Ki-67 score (r2 = 0.37, P = 0.01). It is concluded that altered p53 protein expression is probably an early event in oral carcinogenesis in the floor of the mouth and is associated with dysregulation of cell proliferation at this site.     

Low levels of apoptosis and proliferative activity in colorectal villous tumors: comparison with tubular tumors

In order to clarify the cell kinetics of colorectal villous tumors (VT), 21 villous adenomatous areas and 12 carcinomatous areas within villous adenomas were investigated for proliferative activity and apoptosis and compared with a series of 41 tubular tumors (TT), demonstrating elements of intramucosal carcinomas as well as tubular adenomas (so-called carcinoma in tubular adenoma). Proliferation was estimated in terms of Ki-67 labeling indices and mitotic indices, and apoptosis was assessed by DNA nick-end labeling to give apoptotic indices. Apoptotic indices of villous adenomatous and carcinomatous regions were significantly lower than the values for their tubular counterparts. Ki-67 labeling indices were also significantly lower for adenoma components. Apoptotic indices, Ki-67 labeling indices and mitotic indices increased with atypia raised in tubular adenoma components. Correlations of mitotic indices with apoptotic indices, Ki-67 labeling indices with apoptotic indices and mitotic indices with Ki-67 labeling indices were found for each villous tumor group and tubular tumor group, and the apoptosis and proliferation ratios for villous tumors were relatively low, suggesting a tendency for greater growth due to less cell deletion. Although this is only one of the biological features of villous tumor groups, it might play a major role in generation of malignancy.     

Detection of growth fraction in tumors by Ki67 monoclonal antibody in cytologic smears: a prospective study of 40 cases

The monoclonal antibody (MAb) Ki67 detects a nuclear antigen in cycling tumor cells. Quantitation of proliferating cells is helpful in predicting the recurrence and metastatic potential of tumors as previously reported. We conducted a prospective study on 40 benign and malignant tumors by performing Ki67 immunocytochemical stains on cytologic smears and their corresponding frozen tissues. Quantitation of Ki67 positive cells was done by counting 300 cells in 5-7 high-power fields in cytologic smears and tissues. Only nuclear or nucleolar immunostaining was considered positive for MAb Ki67. The number of Ki67 positive tumor cells in cytologic smears correlated well with Ki67 positive cells from corresponding tissues. On the average, cytologic smears showed 1.9% higher Ki67 positivity in malignant tumors as compared to their corresponding frozen tissues (P < 0.001). The Ki67 positivity in malignant tumors was found to be significantly higher when compared with benign tumors (P < 0.001). We conclude that cytologic smears can be used for the determination of growth potential in tumors by MAb Ki67. Additionally, cytologic preparations can be used during intraoperative consultations when adequate tissue is not available for the above mentioned study.     

Hepatocellular proliferation and development of hepatocellular carcinoma: a case-control study in chronic hepatitis C

Patients with hepatitis C have an increased risk of developing hepatocellular carcinoma (HCC). This is related to the stage of chronic liver disease, as characterized histologically by hepatic fibrosis and architectural distortion, but it is unclear whether histological markers can define the risk of developing HCC. We conducted a case-control immunohistochemical study of Ki-67, a marker for hepatocellular proliferation, in livers of 18 patients who had developed HCC more than 2 years after the biopsy specimen had been taken. Using conditional logistic regression analysis, the results were compared with 18 selected controls, who were age-matched patients with hepatitis C of similar histological stage who had not developed HCC. We also examined livers for cellular dysplasia, p53 mutations, and bcl-2 overexpression, and assessed whether the results could be correlated with demographic and disease-related variables, such as gender, region of birth, alcohol consumption, severity of liver disease, HCV genotype, and markers of hepatitis B virus (HBV) infection. Livers from patients who developed HCC were more often positive for Ki-67 (13 of 18 [72%] v 9 of 18 [50%]; P = .06) and tended to have higher mean Ki-67 scores (6 +/- 7.5 v 3 +/- 4.4; P = .10) compared with control cases. In the HCC-predisposed group, three livers showed large cell dysplasia, two were positive for p53 mutations, and two for bcl-2 overexpression. In contrast, in the non-HCC group, only one case had dysplasia, and none were positive for immunostaining for p53 or bcl-2 mutations. With the exception of one case, all livers with large cell dysplasia or p53 mutations and bcl-2 overexpression were also positive for Ki-67. Twelve (55%) of the 22 Ki-67-positive cases were anti-HBc-positive in the serum, in contrast to 2 of 14 (14%) patients in the Ki-67-negative group (P = .01). Patients with evidence of past infection with HBV were more often Ki-67 positive than those who had no evidence of past infection (85% [11 of 13] v 45% [10 of 22]; P = .02). There were no other associations between demographic or disease-related variables and Ki-67 expression. Increased hepatocellular proliferative activity, as assessed by Ki-67 expression, may be one factor indicative of an increased risk of developing HCC among patients with chronic hepatitis C. Furthermore, past infection with HBV appears to be an important correlate of increased hepatocellular proliferation in hepatitis C.     

Components of the vectorial capacity of Aedes poicilius for Wuchereria bancrofti in Sorsogon province, Philippines

Oncocytic neoplasms of the adrenal gland are rare. We describe the clinicopathologic and immunohistochemical findings of seven oncocytic adrenocortical neoplasms, five oncocytomas, and two oncocytic neoplasms of uncertain malignant potential. Three tumors were studied using electron microscopy. These neoplasms occurred in five women and two men (median age, 55 years) with no clinical evidence that the neoplasms were functional. The size of the neoplasms varied from 5.0 cm to 13.5 cm. Histologically, each neoplasm was composed exclusively of oncocytes. The oncocytomas had very low or absent mitotic activity and no evidence of necrosis. The two oncocytic neoplasms of uncertain malignant potential had increased mitotic activity and necrosis but no evidence of invasion or metastases. Nuclear atypia, either focal or generalized, was found in all neoplasms. Immunohistochemical studies performed using fixed, paraffin-embedded sections showed strong reactivity with the mitochondrial antibody mES-13 in all neoplasms. Four of five oncocytomas and one oncocytic neoplasm of uncertain malignant potential expressed keratin, predominantly keratin 18, as shown using the CAM 5.2 and AE3 antibodies. Two neuroendocrine-associated markers, neuron specific enolase and synaptophysin, were positive in seven and five neoplasms, respectively. However, all neoplasms were negative for the other neuroendocrine markers tested, including chromogranin A, tyrosine hydroxylase, and dopamine beta-hydroxylase, as well as for epithelial membrane antigen, S100, and p53. Using the MIB-1 (Ki-67) antibody, proliferative activity was increased in both oncocytic neoplasms of uncertain malignant potential. All six patients with available clinical follow-up data are alive without evidence disease, although the follow-up interval is relatively short (< 2 years) for the two patients with oncocytic neoplasms of uncertain malignant potential. We conclude that oncocytic adrenocortical neoplasms are nonfunctional tumors that can become large before they are detected by radiologic studies. The majority of neoplasms are benign and should not be misdiagnosed as carcinoma.     

Tumor proliferation, p53 expression, and apoptosis in laryngeal carcinoma: relation to the results of radiotherapy

BACKGROUND: Radiotherapy is used in the treatment of laryngeal carcinoma. The search for biologic parameters that could be used to identify patients who will respond to radiotherapy is crucial. The aim of this study was to determine whether the Ki-67 and p53 indices and the pretreatment apoptotic index would be useful in predicting local control and survival for a group of laryngeal carcinoma patients given postoperative radiotherapy. METHODS: Fifty-seven patients with laryngeal carcinoma treated between 1988 and 1993 were included in this study. Postoperative radiotherapy was given to a mean dose of 57.7 gray (Gy) (range, 50-68; median, 60) in 2-Gy daily fractions. Ki-67 and p53 immunostaining were performed on paraffin-embedded tissue. Cells were evaluated for apoptosis using hematoxylin and eosin-stained slides. Clinicopathologic tumor characteristics were studied in relation to Ki-67, p53, and apoptotic indices, and as prognostic factors for local control and survival in both univariate and multivariate analysis. RESULTS: The Ki-67, p53, and pretreatment apoptotic indices were not related to any clinicopathologic tumor characteristics. Five-year actuarial local control for the whole group was 47%. Patients with tumors that had low Ki-67 proliferation had better long term local control (P < 0.01). and survival (P < 0.03). p53 expression was not predictive of local control or survival in this study. Patients with tumors that had low pretreatment apoptotic indices had better local control (P < 0.049) and survival (P < 0.056) than patients with highly apoptotic tumors. Tumor extension and the pretreatment apoptotic index were significant predictive factors for local control and survival in multivariate analysis. CONCLUSIONS: Ki-67 proliferation measurement and the pretreatment apoptotic index are useful in predicting the clinical outcome of laryngeal carcinoma patients referred for radiotherapy. The role of p53 oncoprotein determination in predicting these outcomes is unclear. Assessment of biologic tumor characteristics could aid in the selection of patients for different treatment strategies.     

New histopathologic data of prognostic value in extra-adrenal paragangliomas. Study of 9 cases

BACKGROUND: The biological behavior of paragangliomas is difficult to evaluate by classic histological criteria thus justifying the use of immunohistochemical markers as prognostic factors. METHODS: Nine extra-adrenal paragangliomas (three jugulo-tympanic, four carotid-body tumors, and two retroperitoneal) were studied by conventional histological criteria, and also by chromogranin A and neuron-specific enolase (NSE) immunohistochemical staining for the study of chief cells, and S-100 as a marker of sustentacular cells. The rate of cell proliferation was studied by the proliferating cell nuclear antigen (PCNA). The correlation between these parameters and the clinical evolution of the neoplasms, which were classified as benign, locally aggressive, and malignant (with metastasis), were also analyzed. RESULTS: The atypia and the mitotic rate did not correlate with the behavior of the tumor. Less immunostaining with the anti-S-100 and anti-chromogranin A antibodies was observed in the malignant paragangliomas and in those which were locally aggressive. In the benign tumors the proliferative rate (PCNA) oscillated between 0.7% and 3.7%, and 40 or less PCNA positive cells were counted in 10 high-power field (HPF) (40x). In malignant and locally aggressive tumors the proliferative rate was 5% or more, with 60 or more cells that were positive for PCNA being found in 10 HPF. CONCLUSIONS: The histopathologic signs implying worse prognosis in extra-adrenal paragangliomas are a decrease in chromogranin A and S-100 immunoreactivity and a rate of cell proliferation of 5% or greater, or a number of cells stained for proliferating cell nuclear antigen greater than 50 in 10 high-power field.     

Intraosseous malignant peripheral nerve sheath tumor in a patient with neurofibromatosis

Malignant peripheral nerve sheath tumors (MPNSTs) are uncommon sarcomas that almost always arise in soft tissue. They can develop in pre-existing neurofibromas or schwannomas, de novo from peripheral nerves, or following radiation therapy. Primary intraosseous MPNST is rare and has been reported most frequently in the mandible. Of the reported cases involving the long bones, none has been associated with neurofibromatosis type 1 (NF-1). We report a case of MPNST arising in the femur in a patient with NF-1.