Distribution of basal/myoepithelial markers in benign and malignant bronchioloalveolar proliferations of the lung.

We investigated the staining pattern of commonly used basal cell/myoepithelial markers, such as p63 (a p53-homologous nuclear protein), basal cell-specific cytokeratin antibody (34betaE12, K903), and smooth muscle myosin heavy chain (SMMHC) in benign and malignant bronchioloalveolar proliferations of the lung. We studied 85 lung lesions consisting of 35 bronchioloalveolar carcinoma, 30 well-differentiated adenocarcinoma, and 20 cases of benign lung lesions. In normal lung, p63, K903, and SMMHC decorated the basal cells of large and small airways and occasional cells of terminal bronchioles. In reactive processes, a distinctive staining pattern was present in 19/20 (95%) of the cases characterized by staining of basal cells of the airways and bronchiolar epithelium and squamous metaplastic epithelium for p63 and K903, whereas 12/20 (60%) stained with SMMHC. Respiratory ciliated cells, alveolar epithelial cells, and nonepithelial cells were negative. In bronchioloalveolar carcinoma, a discontinuous peripheral rim of p63-immunoreactive cells was retained surrounding and intermingled with the malignant bronchioloalveolar proliferation in 31/35 (88.5%) cases, SMMHC in 28/35 (80%) cases, and K903 in 20/35 (57%) cases. For adenocarcinoma, a majority of the cases (28/30, 93%) were negative for p63 and K903; however, SMMHC showed artifactual staining in the desmoplastic stroma in 6/30 (20%) cases. Our results highlighted the differential expression of basal cell markers across various bronchioloalveolar lesions. The staining pattern of basal cells in bronchioloalveolar carcinoma supports that these neoplasms may actually be carcinoma in-situ.

Endoglin (CD105) and vascular endothelial growth factor as prognostic markers in prostatic adenocarcinoma.

We studied endoglin and vascular endothelial growth factor (VEGF) expression as prognostic markers in prostatic adenocarcinoma in 50 radical prostatectomy specimens. Cases were further categorized by Gleason score as follows: 8 to 10, 9 cases; 7(4 + 3), 9 cases; 7 (3 + 4), 14 cases; 6, 13 cases; and 4 or 5, 5 cases. All cases were immunostained for endoglin, CD31, and VEGF. Positively stained microvessels were counted in densely vascular foci in a x 400 field. VEGF staining intensity was scored on a 2-tiered scale. Results were correlated with survival and other parameters. Endoglin demonstrated significantly more microvessels than did CD31 (mean +/- SD, 37 +/- 15 vs 22 +/- 17; P < .001). VEGF expression was low in 21 cases (42%) and high in 29 (58%). Endoglin correlated positively with Gleason score, lymph node metastases, tumor stage, and preoperative prostate-specific antigen level (P < .05) but not with CD31. VEGF correlated significantly with angiolymphatic invasion and Gleason score (P < .05). A high endoglin microvessel count and VEGF expression correlated with shorter survival. Endoglin is a more specific and sensitive marker for tumor angiogenesis than CD31 and may serve as a prognostic marker for prostatic adenocarcinoma.

Pitfalls in the diagnosis of herpes simplex infection in respiratory cytology.

OBJECTIVE: To evaluate the prevalence and potential pitfalls in making an accurate diagnosis of respiratory herpetic infection. STUDY DESIGN: Eighteen cases with the diagnosis of herpes simplex virus (HSV) infection were identified from a total of 7,501 (0.24%) respiratory specimens. All cases were evaluated for classic cytomorphologic features of HSV infection and associated cytologic findings. The parameters studied included number of cells with HSV cytopathic effect, intranuclear inclusions, multinucleation, presence of atypical squamous cells, reparative changes, presence and degree of inflammation and associated obscuring factors. RESULTS: Only a minority of cases (28%) had numerous cells with classic viral cytopathic change. Four (22%) of 18 cases showed atypical squamous cells, and 5 (28%) revealed reparative changes. The majority of the cases were associated with inflammation, which was severe in 4 cases (22%). Blood and degenerative changes obscured the cytologic findings in 3 cases (17%). One case showed a necrotic background. CONCLUSION: Due to the low prevalence of HSV infection in respiratory cytology, a high index of suspicion is necessary for an HSV diagnosis. Pitfalls for a false negative diagnosis include limited number of cells with viral cytopathic change, only mononuclear cells with viral changes and obscuring inflammation or blood. Pitfalls for a false positive diagnosis of malignancy include atypical keratinized squamous cells, atypical repair, cellular degeneration and necrotic background.

The diagnostic utility of D2-40 for malignant mesothelioma versus pulmonary carcinoma with pleural involvement.

Differentiating malignant mesothelioma (MM) from pulmonary carcinoma in pleural fluid cytology can be challenging. Recent studies have suggested that D2-40, a novel lymphatic marker, may be a useful marker for mesothelial differentiation in surgical specimens. However, there are no available data regarding its utility in effusion cytology specimens. We investigated the utility of D2-40 in pleural fluid cytology in differentiating MM from pulmonary carcinomas. Twenty cases of pleural effusion smears of surgically confirmed MM with their corresponding cell blocks were retrieved from the database of the hospital computer system. We also included 10 cases of metastatic pulmonary adenocarcinoma (PA) and 10 cases metastatic pulmonary squamous cell carcinoma (PSCC) involving the pleural fluid. Cell blocks were formalin-fixed, paraffin embedded, and immunostained for TTF1, p63, calretinin, CK5/6, WT-1, and D2-40. Cases were scored as negative (<5% positivity) or positive (>5% moderate/strong positivity). The positive rates for TTF1, p63, calretinin, CK5/6, WT-1, and D2-40 were as follows: MM (0/20), (0/20), (17/20), (18/20), (19/20), (17/20), for PA (8/10), (0/10), (3/10), (0/10), (0/10), (0/10), and for PSCC (1/10), (10/10), (6/10), (10/10), (0/15), (0/10). The staining pattern for D2-40 was characterized by thick membranous staining. Diffuse cytoplasmic staining by D2-40 was seen in 2 cases of pulmonary carcinoma, counted as negative. Our study showed that in differentiating MM from PA, CK5/6, WT-1, and D2-40 have high specificity and sensitivity for MM. Although calretinin is a sensitive IHC marker for MM, it is not specific since it stained 30% of PA. Conversely, to differentiate between MM and PSCC, p63 and WT-1 are the best available markers. We recommend a panel of CK5/6, p63, D2-40, and WT-1 to differentiate MM from pulmonary carcinomas in effusion cytology specimens.

Lymphatic microvessel density as prognostic marker in colorectal cancer.

Lymph node metastases is an important prognostic indicator for disease progression and crucial for therapeutic strategies in the work-up of colorectal carcinoma. In this study, we investigated tumor lymphangiogenesis and vascular endothelial growth factor (VEGF) expression as predictive markers for the risk of lymph node metastasis and their relation to other prognostic parameters in colorectal carcinoma. Resected colorectal carcinomas from 90 patients were examined, including 30 patients without lymph node metastases, 30 with only lymph node metastases, and 30 with liver metastases. Cases were immunostained for CD31, D2-40, and VEGF. Positivity stained microvessels were counted in densely vascular/lymphatic foci (hot spots) at x 400 field (=0.17 mm2). Intensity of staining for VEGF was scored on a two-tiered scale. D2-40 lymphatic microvessel density demonstrated significant correlation with CD31 counts (20+/-9 vs 18+/-6/0.17 mm2 field, P<0.05) and VEGF expression (P<0.01). VEGF was expressed in 61/90 (67%) cases. D2-40 identified lymphatic tumor invasion in 48/90 patients, which was greater than CD31 (37/90) and hematoxylin and eosin (H&E) (31/90). There was a positive significant correlation of D2-40, CD31 counts, and VEGF expression with the presence of lymphovascular invasion and lymph node metastases (P<0.05). D2-40 lymphatic microvessel density correlated significantly with depth of invasion (pT), positive vascular pedicle lymph nodes and liver metastases (P<0.05). In conclusion, D2-40 lymphatic microvessel density showed prognostic significance with positive correlation with lymphovascular invasion, pT, and metastases to lymph nodes and liver. Immunostaining with D2-40 enhances the detection of lymphatic invasion relative to H&E staining and the endothelial marker, CD31.

Clinical significance of a cytologic diagnosis of atypical glandular cells, favor endometrial origin, in Pap smears.

OBJECTIVE: To evaluate the significance of a diagnosis of atypical glandular cells, favor endometrial origin (AGC-EM), using cytohistologic correlation. STUDY DESIGN: A retrospective search identified 90 cervicovaginal smears (vaginal pool) with a diagnosis of AGC-EM, in 2 tertiary care medical centers between January 1998 and December 2002. RESULTS: Forty-six (51%) were conventional preparations and 44 (49%) were liquid-based monolayers (SurePath, TriPath Imaging Inc., Burlington, North Carolina, U.S.A.). Follow-up biopsies were available in 55 of 90 (61%) cases, 15 of 90 (17%) cases had cytology follow-up, and 20 of 90 (22%) were lost to follow-up. The patients ranged in age from 30 to 86 years (mean, 56); 56 of 90 (62%) were > 50 years. Among the patients who underwent biopsy, 22 (40%) had a clinically significant lesion, including 10 (18%) endometrial adenocarcinomas, 8 (15%) endometrial hyperplasias and 4 (7%) high grade squamous intraepithelial lesion/squamous cell carcinoma, nonkeratinizing type. The remaining 33 patients had benign histology, including benign endometrium, endometrial polyp, tubal metaplasia, cystic endometrial atrophy and cervical microglandular hyperplasia. Of the patients with cytologic follow-up, 2 had Pap smears showing atypical squamous cells of undetermined significance, while the remainder had negative results. CONCLUSION: In our study population, 40% (22 of 55) of women who underwent biopsy following a diagnosis of AGC-EM had significant uterine lesions, with the majority of the lesions endometrial in origin. Patients with a diagnosis of AGC-EM, especially those > 50, should be followed closely, and endometrial sampling should be included in their initial workup.

Endoglin (CD105) and vascular endothelial growth factor as prognostic markers in esophageal adenocarcinoma.

Endoglin (CD105), a member of transforming growth factor beta1 receptor complex, has been shown to be a more useful marker to identify tumor angiogenesis than panendothelial markers such as CD31. We investigated endoglin and vascular endothelial growth factor (VEGF) expression as possible prognostic markers in esophageal adenocarcinoma. Surgical specimens from 75 patients with esophageal adenocarcinoma treated with esophagectomy were immunostained for endoglin, CD31, and VEGF. We also included 10 cases of Barrett's esophagus with high-grade dysplasia and 10 cases with Barrett's esophagus low-grade dysplasia. Positively stained microvessels (MVs) were counted in hot spots at magnification of x400. Results were expressed as the highest number of MV identified. For VEGF, intensity of staining was scored on 3-tiered scale. Endoglin demonstrated significantly more vessels than the CD31 (mean, 28.9 +/- 13.2 versus 19.0 +/- 9.4, P < .001). Both endoglin and CD31 MV counts showed significant correlation with stage of the disease (r = 0.59, P < .001; r = 0.52, P < .001, respectively) and patient survival (log rank P < .01). Only endoglin MV count was significantly correlated with the presence of angiolymphatic invasion (r = 0.34, P < .05) and lymph node (LN) metastases (r = 0.48, P < .001). Univariate analysis showed that endoglin MV count is an independent prognostic factor. Endoglin showed a significant increase in MV count in Barrett's esophagus with high-grade dysplasia when compared with Barrett's esophagus low-grade dysplasia (P < .01), whereas CD31 did not show any significant difference. VEGF was expressed in 48 (64%) of 75 cases of adenocarcinoma and was significantly correlated with angiolymphatic invasion, LN metastases, and survival. In conclusion, endoglin is a specific and sensitive marker for tumor angiogenesis. Endoglin staining also showed prognostic significance with positive correlation with the presence of angiolymphatic invasion, LN metastases, tumor stage, and survival.

The value of epithelial membrane antigen expression in separating benign mesothelial proliferation from malignant mesothelioma: a comparative study.

Differentiating reactive mesothelial (RM) proliferation from malignant mesothelioma (MM) can be cytologically challenging. There have been discordant studies reporting the value of epithelial membrane antigen (EMA) in differentiating RM from MM. In this study, we investigated the expression of two different clones of EMA in RM and MM. Twenty cases of pleural effusion smears of RM and 20 cases of MM with their corresponding cell blocks were retrieved from the hospital computer system. Diagnosis of MM was confirmed by surgical decortication or pneumonectomy with immunostaining studies and/or electron microscopy. Cases of RM were confirmed by clinical history and histology. Cell blocks were formalin-fixed, paraffin-embedded, and immunostained for EMA clone Mc5 and EMA clone E29. The positive rates for clone Mc5 were 14/20 (70%) for MM and 12/20 (60%) for RM and EMA clone E29 were 15/20 (75%) for MM and 0/20 (0%) for RM. The sensitivity and specificity for EMA clone Mc5 were 70 and 40%, respectively. For EMA clone E29, the sensitivity and specificity were 75 and 100%, respectively. In conclusion, both RM and MM immunostained for EMA clone Mc5, indicating that it is not a reliable immunocytochemical marker for differentiating RM from MM. EMA clone E29 was negative in all cases of RM and positive in 75% of MM and therefore is a reliable immunocytochemical marker for differentiating RM from MM.

Prognostic significance of thyroid transcription factor-1 expression in both early-stage conventional adenocarcinoma and bronchioloalveolar carcinoma of the lung.

Thyroid transcription factor 1 (TTF-1) is a diagnostic immunohistochemical marker for primary pulmonary neoplasms, but its utility as a prognostic marker is not well established. Surgical specimens from 100 cases of pulmonary adenocarcinoma were retrieved from the hospital computer system, including 50 cases of conventional adenocarcinoma (CA) and 50 cases of bronchioloalveolar adenocarcinoma (BAC) (32 nonmucinous type and 18 mucinous type). Representative sections were immunostained for TTF-1. Positive immunohistochemical study was correlated with other prognostic parameters. In the CA group, strong or moderate TTF-1 expression was seen in 30 of 50 (60%) patients and was associated with significantly better survival compared with those patients having weak staining (7 cases; 14%) or negative staining (13 cases; 26%) (P <0.01; log-rank test). Spearman and Pearson's correlation showed no significant correlation between TTF-1 expression and tumor grade, size, recurrence, or vascular invasion; therefore, TTF-1 was considered an independent predictor of survival. In the BAC group, TTF-1 was strongly expressed in 34 of 50 cases (68%) and was negative in 16 of 50 cases (32%), including 14 mucinous BACs. Although TTF-1 immunoreactivity was not statistically associated with good survival in BAC patients, those patients with strong immunohistochemical expression showed a trend toward longer survival. Our results indicate that TTF-1 positivity is an independent predictor of better survival, especially in patients with CA. Mucinous and nonmucinous BACs exhibit disparate staining patterns with TTF-1, with nonmucinous BAC demonstrating greater positivity. Although nonmucinous BAC patients showing strong positive staining had longer survival, the difference was not statistically significant, which is probably related to the overall good survival of patients with early-stage BAC.

Diagnostic value of HepPar1, pCEA, CD10, and CD34 expression in separating hepatocellular carcinoma from metastatic carcinoma in fine-needle aspiration cytology.

Differentiating primary and metastatic hepatic malignancies can be diagnostically challenging in fine-needle aspiration cytology (FNAC). We compared four immunohistochemical (IHC) markers, pCEA, CD10, HepPar1, and CD34, in differentiating hepatocellular carcinoma (HCC) from metastatic carcinoma (MC) in FNAC specimens. Sixty cases of liver FNAC with their corresponding cell blocks were retrieved from the hospital computer system, including 30 HCC and 30 MC (15 colon, 10 breast, and 5 pancreas). The diagnoses were confirmed by clinical follow-up and surgical resection or core needle biopsy. The direct cytologic smears were air-dried and Diff-Quik-stained, and alcohol-fixed and Papanicolaou-stained. Cell block sections from the aspirates were immunostained for pCEA, CD10, HepPar1, and CD34. IHC on cytologic smears for HCC was performed on 10 cases and compared with the cell block results. In HCC, CD10, and pCEA demonstrated the characteristic canalicular staining in 23/30 (77%) and 24/30 (80%) of the cases, respectively; however, none of the MC showed a canalicular staining pattern. HepPar1 was positive in 26/30 (87%) of the HCC cases and one MC. CD34 stained sinusoidal endothelial cells in 27/30 (90%) cases of HCC and six MC. Our results demonstrate that the canalicular staining pattern for CD10 and sinusoidal staining pattern of CD34 are very specific, in addition to the high specificity and sensitivity of HepPar1 for HCC. Cell blocks were more informative in demonstrating the characteristic architecture and immunostaining pattern of the malignancy than the cytologic smears. An IHC panel consisting of pCEA, CD10, HepPar1, and CD34 is useful for confirming HCC in FNAC of the liver.

Endoglin (CD105) and vascular endothelial growth factor as prognostic markers in colorectal cancer.

Endoglin (CD105) has been shown to be a more useful marker to identify proliferating endothelium involved in tumor angiogenesis than panendothelial markers such as CD31. We investigated endoglin and vascular endothelial growth factor expression as possible prognostic markers in colorectal cancer. Surgical specimens from 150 patients with resected colorectal carcinomas were immunostained for endoglin, CD31 and vascular endothelial growth factor. Colorectal carcinoma cases consisted of 50 cases without lymph node metastases, 50 cases with only lymph node metastases and 50 cases with liver metastases (38 cases also had positive lymph nodes). Positively stained microvessels were counted in densely vascular foci (hot spots) at x 400 fields in each specimen. For vascular endothelial growth factor, intensity of staining was scored on a three-tiered scale. Results were correlated with other prognostic parameters. Endoglin demonstrated significantly more proliferating neoplastic microvessels than CD31 (31+/-10 vs 19+/-8/0.15 mm2 field, P<0.001). Low vascular endothelial growth factor expression within tumor cells was seen in 49 (33%) and high expression in 101 cases (67%). There was a positive correlation of endoglin, CD31 counts and vascular endothelial growth factor overexpression with the presence of angiolymphatic invasion and lymph node metastases (P<0.05). Only endoglin counts correlated significantly with liver metastases and positive vascular pedicle lymph nodes (P<0.05), while vascular endothelial growth factor showed significant correlation with the depth of invasion (P<0.01). Endoglin, by staining higher numbers of the proliferating vessels in colon carcinoma, is a more specific and sensitive marker for tumor angiogenesis than the commonly used panendothelial markers. Endoglin staining also showed prognostic significance with positive correlation with angiolymphatic invasion and metastases to lymph nodes and liver.