Abstract P2-03-01: Analytical validation of a standardized scoring protocol for Ki67 assessed on breast excision whole sections: An international multicenter collaboration

Aims: (i) Determine whether between-observer reproducibility for Ki67 when assessed on whole sections according to a standardized scoring protocol is adequate for clinical application. (ii) Compare between-observer reproducibility of Ki67 scores assessed on hot-spots to scores using a global method that averages across a tissue section.

Background: The nuclear proliferation biomarker Ki67 has multiple potential roles in breast cancer, including aiding decisions based on prognosis, but unacceptable levels of between-laboratory variability have been observed. The International Ki67 in Breast Cancer Working Group has undertaken a systematic program to determine whether Ki67 measurement can be analytically validated and standardized across labs. In phase 1, variability in visual interpretation was identified as an important source of variability. Phases 2 and 3a showed that adherence to defined scoring methods substantially improved reproducibility in scoring tissue microarrays and core-cut biopsies. We now assess whether acceptable reproducibility can be achieved on whole sections.

Methods: Adjacent sections from 30 primary ER+ breast cancers were centrally stained for Ki67 to assemble 4 sets of 30 stained tumor sections, circulated around 23 labs in 12 countries. Ki67 was scored by 2 methods by all labs: (a) global: 4 fields of 100 tumor cells each were selected to reflect observed heterogeneity in nuclear staining (b) hot-spot: the field with highest Ki67 percentage of tumor cells with nuclear staining was selected and up to 500 cells scored. Ki67 scores were log2-transformed for statistical analyses and back-transformed for presentation. The primary objective was to assess whether either method could achieve an intraclass correlation coefficient (ICC) significantly greater than 0.8, considered substantial to almost-perfect reproducibility. Secondary objectives were to assess which method had highest observed ICC and to assess whether observers identified the same “hot-spots”.

Results: ICC for the global method was 0.87 (95%CI: 0.799-0.93), marginally meeting the prespecified success criterion. The ICC for the hot-spot method was 0.83 (95%CI: 0.74-0.90) and had a CI extending below the success criterion. Across the 23 labs, geometric mean value of the 30 scores ranged from 8.5 to 19.6 for the global method and from 12.8 to 30.3 for the hot-spot method. The overall mean (95% CI) of these values was 12.9 (11.9-14.0) and 20.9 (19.1-22.8), respectively. Visually, between-laboratory agreement in location of selected hot-spot varies between cases. The median times for scoring were 9 and 6 minutes for global and hot-spot methods respectively.

Conclusions: The global method marginally met the prespecified criterion of success; it should now be evaluated for clinical validity in appropriate cohorts of cases. The hot-spot method was observed to have slightly less reproducibility between labs. The time taken for scoring by either method is practical using counting software we are making publicly available. Establishment of external quality assessment schemes is likely to improve the reproducibility between labs further.

(Supported by a grant from the Breast Cancer Research Foundation)

Citation Format: Nielsen TO, Leung SCY, Zabaglo LA, Arun I, Badve SS, Bane AL, Bartlet JMS, Borgquist S, Chang MC, Dodson A, Ehinger A, Fineberg S, Focke CM, Gao D, Gown AM, Gutierrez C, Hugh JC, Kos Z, Lænkholm A-V, Mastropasqua MG, Moriya T, Nofech-Mozes S, Osborne CK, Penault-Llorca FM, Piper T, Sakatani T, Salgado R, Starczynski J, Sugie T, van der Vegt B, Viale G, Hayes DF, McShane LM, Dowsett M. Analytical validation of a standardized scoring protocol for Ki67 assessed on breast excision whole sections: An international multicenter collaboration [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P2-03-01.

Abstract P1-07-01: Attainment of extremely high concordance rates between fluorescence in situ hybridization and immunohistochemistry in testing for human epidermal growth factor receptor 2 (HER2) in breast cancer using a normalized scoring system for immunohistochemistry: a four year experience with over 9000 cases

Background: The 2007 ASCO-CAP guidelines mandate a high level (95%) of concordance between different testing modalities such as fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) for demonstration of the human epidermal growth factor receptor 2 (HER2) status in breast cancer. As few laboratories had been able to attain this level of concordance, the ASCO-CAP guidelines mandated regulation of pre-analytical variables such as fixation time in an attempt to improve concordance. We wished to test our hypothesis that the major reason for discordance between IHC and FISH results is false positive IHC, i.e., IHC 3+ immunostaining in cases which are non amplified by FISH, and that the vast majority of these false positives can be eliminated by using a normalized IHC scoring system.

Materials and Methods: A total of 9,022 breast cancer cases, representing all those submitted to PhenoPath Laboratories for FISH testing from pathology laboratories around the United States between September 2008 and May 2012, had parallel sections immunostained with the rabbit monoclonal antibody SP3 to the HER2 gene product, with localization via a polymer based detection system. Tumor was scored according to ASCO-CAP criteria, as 0, 1+, 2+ or 3+; however, scoring was tabulated in two ways. The first was an absolute HER2 score based solely on analysis of the carcinoma, and the second was a normalized HER2 score, obtained by subtracting the score of the non-neoplastic breast epithelium from that of the infiltrating cancer. FISH was performed using the Vysis PathVysion combined HER2 and CEP17 probe kit with morphometric analysis performed using a MetaSystems image analysis system that incorporated the Metafer software. A score of > 2.2 was required for classification as amplified, and <1.8 for classification as non amplified.

Results: Using the standard scoring system, negative concordance (0 or 1+ IHC, non-amplified by FISH) was obtained in 3448/3496 (98.6%) of cases, and positive concordance (3+ IHC, amplified by FISH) was obtained in 502/666 (75.3%) of cases, indicating the presence of significant numbers of falsely IHC positive cases. However, using the normalization method, the negative concordance rate remained unchanged at 3903/3960 (98.6%) but the positive concordance rate improved to 450/463 (97.2%). The absolute number of false IHC positive cases, using the normalization method, was reduced by over 90%, from 164 to 13.

Discussion: Extremely high concordance rates, with elimination of the vast majority of false IHC positive cases, can be attained in a clinical laboratory examining tissues from divergent sources, even in the absence of controlling pre-analytical variables, by employing a normalized scoring system for IHC.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P1-07-01.

Multivariate analysis of expression of the microtubule-associated protein, tau, predicts improved progression free and overall survival in patients with metastatic HER-2-negative breast cancers treated with docetaxel and vinorelbine plus filgrastim

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Background: Drugs that poison the mitotic spindle, including taxanes and vinca alkaloids, are active agents against breast cancer. Preliminary evidence showed that high expression levels of tau predicted improved PFS and OS in patients with metastatic HER-2-negative breast cancers treated with docetaxel and vinorelbine plus filgrastim. We now tested whether levels of tau and another microtubule associated protein, beta-tubulin, could predict PFS and OS in multivariate analysis using other prognostic marker studies, including ER, PR, p53 and Ki-67 on a tissue microarray (TMA) obtained from patients in the SWOG S0102 trial. Materials and Methods: Immunohistochemistry (IHC) using antibodies to tau, beta-tubulin, ER, PR, p53, and Ki-67 was performed on a TMA constructed from the S0102 paraffin blocks. All markers were scored semiquantitatively from 0 to 3. Progression free survival (PFS) and overall survival (OS) were evaluated using multivariate analysis. Results: A total of 38 patients (41.3%) were evaluated. Tau was positively correlated with ER (r=0.36; p=0.0325) and PR (r=0.63; p<0.0001), but not with beta tubulin (p=0.34), Ki-67 (p=0.58), or age (p=0.73). Beta tubulin was not significantly correlated with any other markers. Adjusting for age, there was a significant effect of tau expression on OS (HR=0.667, p= 0.0193) and PFS (HR=0.653; p=0.0035), with higher tau associated with longer survival. When adjusted for both age and PR, there was a marginally significant effect of tau on OS (HR=0.582; p=0.056) and PFS (HR=0.604; p= 0.065). Beta tubulin was not associated with OS (HR=0.909; p=0.66) and PFS (HR=0.904; p=0.58) adjusted for age. Conclusions: In multivariate analysis, identification of breast cancer specimens showing high expression levels of tau predicts improved PFS and OS in patients with metastatic HER-2-negative breast cancers treated with docetaxel and vinorelbine plus filgrastim. High expression of tau also correlated with PR and ER expression. These results confirm and expand earlier studies of the predictive power of tau in a multivariate analysis using a panel of IHC markers for breast cancer.

No significant financial relationships to disclose.

p63 Expression in Lung Carcinoma

p63 is a recently discovered member of the p53 family that has been shown to be important in the development of epithelial tissues. p63 may also play a role in squamous cell carcinomas of the lung, head and neck, and cervix, and its expression is increased in these tumors. The purpose of this study was to investigate the expression of p63 in a broad spectrum of histologic types of lung tumors. A total of 441 cases of primary lung tumors with follow-up data were identified, and the paraffin-embedded tissue blocks were used to construct a duplicate core tissue microarray. After review of the tissue cores, 408 cases, consisting of 123 squamous cell carcinomas, 93 adenocarcinomas, 68 large cell carcinomas, 68 classic carcinoids, 31 atypical carcinoids, 11 large cell neuroendocrine carcinomas, and 14 small cell carcinomas, were adequate for analysis. Immunohistochemistry was performed at 2 different laboratories using monoclonal antibody 4A4 to detect the expression of p63, using different staining protocols. p53 expression was also studied with immunohistochemistry using monoclonal antibody DO-7. Kaplan-Meier curves were plotted to compare the survival of p63-expressing versus nonexpressing tumors. A large proportion of squamous cell carcinomas expressed p63 (96.9%), most showing strong positive nuclear immunoreactivity. Expression in other nonsmall cell lung cancers was also present. Thirty percent of adenocarcinomas and 37% of large cell carcinomas showed p63 expression. In the neuroendocrine tumors, an increasing proportion of tumors stained for p63 as tumor grade increased; 1.9% of classic carcinoids, 30.8% of atypical carcinoids, 50% of large cell neuroendocrine carcinomas, and 76.9% of small cell carcinomas were positive. Approximately half of the positively staining neuroendocrine cases showed strong staining. Expression of p63 was of prognostic significance in neuroendocrine tumors (P < 0.0001), with higher-grade tumors more likely to express p63. Correlation between p63 and p53 expression was not observed (P = 0.18) in nonsmall cell lung cancer; however, a significant correlation between the 2 markers was found in neuroendocrine tumors (P < 0.0001). p63 staining was repeated with a different staining protocol, yielding similar results overall but a lower percentage of positive cases (34.2% vs. 48.4% of tumors positive). In conclusion, p63 expression is consistently expressed in squamous cell carcinoma in the lung, but is also expressed in a subset of adenocarcinomas and large cell carcinomas. Pulmonary neuroendocrine tumors also show p63 staining in some instances, particularly in higher-grade tumors, and the majority of small cell carcinomas are p63-positive. These results suggest that p63 may be involved in oncogenesis in a broader range of tumors than was previously thought.

P504S immunohistochemical detection in 405 prostatic specimens including 376 18-gauge needle biopsies

P504S is a recently described, prostate cancer-specific gene that encodes a protein involved in the beta-oxidation of branched chain fatty acids. A recent study has shown that immunohistochemical detection of P504S gene product is a sensitive and specific marker of prostatic carcinoma in formalin-fixed, paraffin-embedded tissues. We performed a detailed analysis of P504S protein expression in a large series of prostate and bladder specimens with special emphasis on staining in specific morphologic patterns of prostatic adenocarcinoma, posthormonal and radiation therapy cases, and invasive urothelial carcinoma. A total of 366 prostate needle core biopsies from 124 patients with prostate cancer, 10 biopsies from 2 patients without prostate cancer, 28 prostatectomy specimens (16 with specific morphologic patterns, 7 posthormonal therapy and 5 postradiation therapy specimens), 5 bladder specimens with invasive urothelial carcinoma, and a single transurethral resection specimen from a patient with hormonally treated prostate cancer and invasive urothelial carcinoma were stained with P504S monoclonal antibody at a 1:250 dilution using standard heat-induced epitope retrieval and avidin-biotin technique. Extent (0, no staining; 1+, 1-10% staining; 2+, 11-50% staining; 3+, > or =51% staining) and location (luminal, subluminal, and diffuse cytoplasmic) of immunoreactivity in carcinoma and benign tissues were recorded. A total of 153 of 186 biopsies (82%) with prostatic adenocarcinoma stained for P504S. Pseudohyperplastic, atrophic, ductal, and mucinous prostatic carcinomas stained similarly, as did cases treated with hormone or radiotherapy. In 81 of 377 (21%) foci of benign prostatic tissue there was staining that was almost always focal, faint, and noncircumferential. Seminal vesicles did not stain for P504S. Five of six (83%) specimens with invasive urothelial carcinoma had 2+ staining and one case had focal staining. We conclude that immunohistochemistry for P504S has potential utility in the diagnosis of prostate cancer, including those treated by hormones and radiation. Circumferential luminal to subluminal and diffuse cytoplasmic staining is the most specific staining pattern for prostatic carcinoma and is almost never associated with benign prostatic tissue. However, a negative P504S immunostain does not automatically rule out prostate cancer, as 18% of cases were negative. Additionally, occasional benign glands, high-grade prostatic intraepithelial neoplasia, atypical adenomatous hyperplasia, and urothelial carcinoma may express P504S. Therefore, we think that P504S is best used only in conjunction with strict light microscopic correlation and preferably with high molecular weight cytokeratin immunostaining.

Low-grade (fibromatosis-like) spindle cell carcinoma of the breast

Spindle cell carcinoma of the breast, a variant of metaplastic carcinoma, includes a wide spectrum of lesions with histomorphologic and nuclear features ranging from overtly malignant to mildly atypical. Spindle cell carcinomas with mildly atypical features may resemble fasciitis, fibromatosis, or myofibroblastic tumors and therefore are often misinterpreted as such. A recent study has suggested that spindle cell carcinomas with a dominant fibromatosis-like phenotype, unlike spindle cell carcinomas in general, have no propensity for distant metastasis and should be termed "tumors" rather than "carcinomas." To investigate the question of fibromatosis-like spindle cell breast carcinoma (FLSpCCs) metastatic potential, we studied cases of FLSpCC seen at the University of Texas M.D. Anderson Cancer Center between 1987 and 2000. Clinical, pathologic, and immunophenotypic features were reviewed, with emphasis on biologic behavior and predictors of clinical outcome. Our series included 24 women who ranged in age from 55 to 85 years (mean 66 years). Tumor size ranged from 1.0 to 5 cm (mean 2.8 cm). Most tumors were grossly well defined but had microscopic infiltrative borders. Tumors showed a dominant fibromatosis-like or myofibroblastic-like growth pattern with prominent collagenization. Inflammatory infiltrate was noted in the majority of tumors. Cytokeratin-positive cells were seen in all cases and usually appeared as cords or sheets of polygonal cells; isolated cytokeratin-positive cells were rare. In most tumors immunoreactivity for smooth muscle actin (SMA) was confined to the cytokeratin-negative cells. In five cases intense co-expression of cytokeratin and SMA was noted. None of the tumors showed immunoreactivity for smooth muscle heavy chain myosin, estrogen receptors, progesterone receptors, or HER-2/neu. Ki-67 expression was noted in fewer than 5% of tumor cells. Treatment consisted of local excision (seven cases) or modified radical mastectomy (13 cases). Treatment was unknown in four cases. In patients who underwent axillary nodal dissection, no lymph node metastases were found. Two of the six patients who underwent local excision developed local recurrence. Two patients who underwent modified radical mastectomy developed lung metastases within 2 years after the initial diagnosis. The metastatic tumors were histologically similar to the primary tumors. Our findings indicate that FLSpCCs have the potential for local recurrence and distant metastasis and should be treated accordingly. Because FLSpCCs may be underdiagnosed as benign, the use of immunohistochemical studies, especially for cytokeratins and SMA, is essential in the evaluation of any spindle cell proliferations of the breast.

Renal angiomyolipoma: further immunophenotypic characterization of an expanding morphologic spectrum

BACKGROUND

Renal angiomyolipoma is a benign tumor histologically characterized by proliferation of spindle cells, epithelioid cells, and adipocytic cells in concert with many thick-walled blood vessels. To add further diagnostic confusion, an epithelioid cell-predominant variant of renal angiomyolipoma has recently been described. HMB-45 immunoreactivity correlates with ultrastructural striated organelles that closely resemble premelanosomes, although no evidence of melanogenesis has been documented in this tumor.

OBJECTIVE

To further characterize the immunophenotypic and ultrastructural profile of renal angiomyolipoma based on phenotypic cell type (epithelioid, spindle, and adipocytic cell).

DESIGN

Formalin-fixed, paraffin-embedded tissues from 27 renal angiomyolipomas and 8 renal cell carcinomas were immunostained with monoclonal antibodies to the melanoma-associated antigens HMB-45, HMB-50, NKI/C3 (CD63), and tyrosinase; the smooth muscle-related antigens calponin and muscle-specific actin (HHF-35); S100; and cytokeratin (CK). All renal angiomyolipomas were also immunostained with a polyclonal antibody to renin. Ultrastructural examination was performed on 9 selected cases.

RESULTS

All renal angiomyolipomas stained positive for HMB-45, HMB-50, NKI/C3, muscle-specific actin (HHF-35), and calponin. Overall, HMB-45, HMB-50, and NKI/C3 preferentially stained the epithelioid cells. Tyrosinase staining was present in 50% of the renal angiomyolipomas with adequate tissue for staining (12 of 24 cases); positive staining and intensity paralleled HMB-45, HMB-50, and NKI/C3. Muscle-specific actin (HHF-35) and calponin preferentially stained the spindle cells. The adipocytic cells stained positive for both melanoma-associated antigens and smooth muscle antigens. Epithelioid cells, spindle cells, and adipocytic cells were CK, S100, and renin negative. Ultrastructural findings paralleled immunohistochemical staining patterns. Premelanosome-like organelles and electron dense granules were more readily detected in the epithelioid cells within the tumor, whereas ultrastructural characteristics of smooth muscle cells were more easily found in the spindle cells. All renal cell carcinomas stained positive for CK, NKI/C3 staining was variable, and all were negative for HMB-45, HMB-50, smooth muscle actin (HHF-35), and calponin.

CONCLUSION

In renal angiomyolipoma, the epithelioid and spindle cells have preferential staining patterns for melanoma-associated antigens versus smooth muscle antigens, respectively. Positivity in renal angiomyolipoma for HMB-50, NKI/C3, and tyrosinase, in addition to HMB-45, provides evidence for the presence of different melanoma-associated gene products. Immunophenotypic overlap of the 3 histologically distinct renal angiomyolipoma cell populations suggests a common cell line, supporting a unitarian concept for renal angiomyolipoma. Ultrastructural characteristics of the 3 renal angiomyolipoma cell phenotypes parallel the immunophenotype, giving further support to a common cell line. Our study lends further credence to the perivascular epithelioid cell concept as proposed by Bonetti and colleagues.

Renal angiomyolipoma: further immunophenotypic characterization of an expanding morphologic spectrum

BACKGROUND

Renal angiomyolipoma is a benign tumor histologically characterized by proliferation of spindle cells, epithelioid cells, and adipocytic cells in concert with many thick-walled blood vessels. To add further diagnostic confusion, an epithelioid cell-predominant variant of renal angiomyolipoma has recently been described. HMB-45 immunoreactivity correlates with ultrastructural striated organelles that closely resemble premelanosomes, although no evidence of melanogenesis has been documented in this tumor.

OBJECTIVE

To further characterize the immunophenotypic and ultrastructural profile of renal angiomyolipoma based on phenotypic cell type (epithelioid, spindle, and adipocytic cell).

DESIGN

Formalin-fixed, paraffin-embedded tissues from 27 renal angiomyolipomas and 8 renal cell carcinomas were immunostained with monoclonal antibodies to the melanoma-associated antigens HMB-45, HMB-50, NKI/C3 (CD63), and tyrosinase; the smooth muscle-related antigens calponin and muscle-specific actin (HHF-35); S100; and cytokeratin (CK). All renal angiomyolipomas were also immunostained with a polyclonal antibody to renin. Ultrastructural examination was performed on 9 selected cases.

RESULTS

All renal angiomyolipomas stained positive for HMB-45, HMB-50, NKI/C3, muscle-specific actin (HHF-35), and calponin. Overall, HMB-45, HMB-50, and NKI/C3 preferentially stained the epithelioid cells. Tyrosinase staining was present in 50% of the renal angiomyolipomas with adequate tissue for staining (12 of 24 cases); positive staining and intensity paralleled HMB-45, HMB-50, and NKI/C3. Muscle-specific actin (HHF-35) and calponin preferentially stained the spindle cells. The adipocytic cells stained positive for both melanoma-associated antigens and smooth muscle antigens. Epithelioid cells, spindle cells, and adipocytic cells were CK, S100, and renin negative. Ultrastructural findings paralleled immunohistochemical staining patterns. Premelanosome-like organelles and electron dense granules were more readily detected in the epithelioid cells within the tumor, whereas ultrastructural characteristics of smooth muscle cells were more easily found in the spindle cells. All renal cell carcinomas stained positive for CK, NKI/C3 staining was variable, and all were negative for HMB-45, HMB-50, smooth muscle actin (HHF-35), and calponin.

CONCLUSION

In renal angiomyolipoma, the epithelioid and spindle cells have preferential staining patterns for melanoma-associated antigens versus smooth muscle antigens, respectively. Positivity in renal angiomyolipoma for HMB-50, NKI/C3, and tyrosinase, in addition to HMB-45, provides evidence for the presence of different melanoma-associated gene products. Immunophenotypic overlap of the 3 histologically distinct renal angiomyolipoma cell populations suggests a common cell line, supporting a unitarian concept for renal angiomyolipoma. Ultrastructural characteristics of the 3 renal angiomyolipoma cell phenotypes parallel the immunophenotype, giving further support to a common cell line. Our study lends further credence to the perivascular epithelioid cell concept as proposed by Bonetti and colleagues.

Renal angiomyolipoma: further immunophenotypic characterization of an expanding morphologic spectrum

BACKGROUND

Renal angiomyolipoma is a benign tumor histologically characterized by proliferation of spindle cells, epithelioid cells, and adipocytic cells in concert with many thick-walled blood vessels. To add further diagnostic confusion, an epithelioid cell-predominant variant of renal angiomyolipoma has recently been described. HMB-45 immunoreactivity correlates with ultrastructural striated organelles that closely resemble premelanosomes, although no evidence of melanogenesis has been documented in this tumor.

OBJECTIVE

To further characterize the immunophenotypic and ultrastructural profile of renal angiomyolipoma based on phenotypic cell type (epithelioid, spindle, and adipocytic cell).

DESIGN

Formalin-fixed, paraffin-embedded tissues from 27 renal angiomyolipomas and 8 renal cell carcinomas were immunostained with monoclonal antibodies to the melanoma-associated antigens HMB-45, HMB-50, NKI/C3 (CD63), and tyrosinase; the smooth muscle-related antigens calponin and muscle-specific actin (HHF-35); S100; and cytokeratin (CK). All renal angiomyolipomas were also immunostained with a polyclonal antibody to renin. Ultrastructural examination was performed on 9 selected cases.

RESULTS

All renal angiomyolipomas stained positive for HMB-45, HMB-50, NKI/C3, muscle-specific actin (HHF-35), and calponin. Overall, HMB-45, HMB-50, and NKI/C3 preferentially stained the epithelioid cells. Tyrosinase staining was present in 50% of the renal angiomyolipomas with adequate tissue for staining (12 of 24 cases); positive staining and intensity paralleled HMB-45, HMB-50, and NKI/C3. Muscle-specific actin (HHF-35) and calponin preferentially stained the spindle cells. The adipocytic cells stained positive for both melanoma-associated antigens and smooth muscle antigens. Epithelioid cells, spindle cells, and adipocytic cells were CK, S100, and renin negative. Ultrastructural findings paralleled immunohistochemical staining patterns. Premelanosome-like organelles and electron dense granules were more readily detected in the epithelioid cells within the tumor, whereas ultrastructural characteristics of smooth muscle cells were more easily found in the spindle cells. All renal cell carcinomas stained positive for CK, NKI/C3 staining was variable, and all were negative for HMB-45, HMB-50, smooth muscle actin (HHF-35), and calponin.

CONCLUSION

In renal angiomyolipoma, the epithelioid and spindle cells have preferential staining patterns for melanoma-associated antigens versus smooth muscle antigens, respectively. Positivity in renal angiomyolipoma for HMB-50, NKI/C3, and tyrosinase, in addition to HMB-45, provides evidence for the presence of different melanoma-associated gene products. Immunophenotypic overlap of the 3 histologically distinct renal angiomyolipoma cell populations suggests a common cell line, supporting a unitarian concept for renal angiomyolipoma. Ultrastructural characteristics of the 3 renal angiomyolipoma cell phenotypes parallel the immunophenotype, giving further support to a common cell line. Our study lends further credence to the perivascular epithelioid cell concept as proposed by Bonetti and colleagues.

Immunohistochemical distinction of endometrial stromal sarcoma and cellular leiomyoma

Distinguishing low grade endometrial stromal sarcoma (ESS) from benign smooth muscle proliferations like cellular leiomyoma (CL) can be problematic; because of differing treatments and prognosis, this distinction is important. The authors tested the hypothesis that low grade ESS could be distinguished from CL by immunohistochemistry using a panel of antibodies that have not previously been used in this setting. Antibodies to calponin, smooth muscle myosin heavy chain (SMM-HC), the Wilms tumor gene product (WT-1), and CD10 were applied to 14 cases of ESS (10 low grade, 4 high grade) and 9 CL. Among low grade ESS, 3 of 10, 3 of 10, 9 of 10, and 10 of 10 were positive for expression of calponin, SMM-HC, WT-1, and CD10, respectively. Of CL, all 9 were positive for calponin, SMM-HC, and WT-1, whereas 3 of 9 marked with antibodies to CD10. Overall, SMM-HC and calponin were expressed strongly in CL but weakly expressed in ESS; the converse was true for CD10. Expression of WT-1 and the reticulin-staining pattern do not discriminate between these two tumors. Antibodies to SMM-HC, CD10, and calponin can reliably distinguish ESS from CL.

Quantitative evaluation of HER-2/neu status in breast cancer by fluorescence in situ hybridization and by immunohistochemistry with image analysis

We correlated quantitative results obtained in 40 invasive breast cancer cases for HER-2 gene amplification by fluorescence in situ hybridization with protein expression by immunohistochemical studies with computer-assisted image analysis. Fluorescence in situ hybridization (FISH) results were quantified as the mean number of fluorescent signals per nucleus, and immunohistochemical slides were read by semiquantitatively assessing membranous immunostaining intensity in tumor cells vs nonneoplastic breast tissue or quantitatively evaluated by image analysis. We found high correlation between immunohistochemical results by semiquantitative scoring and by image analysis. FISH results correlated with immunohistochemical results moderately when the staining intensity of only tumor cells was assessed and significantly better when the difference in staining intensity between tumor cells and nonneoplastic breast tissue was assessed. The correlation with FISH results was further improved when immunohistochemical study was combined with heat-induced epitope retrieval (HIER). Although FISH and immunohistochemical studies assess different aspects of the HER-2/neu gene (amplification vs overexpression), we found good correlation between the diagnostic techniques. The correlation was best when immunohistochemical studies were combined with HIER and assessed as the difference between tumor cells and nonneoplastic breast tissue.

E-cadherin reactivity of 95 noninvasive ductal and lobular lesions of the breast. Implications for the interpretation of problematic lesions

Studies suggest that E-cadherin is useful to classify epithelial breast lesions as ductal or lobular, but extensive experience with this antibody is lacking. We studied reactivity of lesions with classic and indeterminate morphologic features. We reviewed 95 lesions and divided them into unanimous and nonunanimous diagnosis groups; the unanimous group served as benchmark lesions to which E-cadherin reactivity could be standardized and compared. All 37 ductal lesions in the unanimous group had strong, diffuse E-cadherin reactivity. Two of 22 classic lobular carcinoma in situ (LCIS) lesions had sparse E-cadherin-reactive lobular cells within a few terminal duct lobular units. Neither displayed transition from nonreactive to reactive cells. Of 36 lesions in the nonunanimous group, 19 had insufficient morphologic features for definitive classification. Only 6 of 19 were E-cadherin reactive, including several minimally proliferative lesions. The other 17 lesions in the nonunanimous group had LCIS and ductal carcinoma in situ (DCIS) features. All had no E-cadherin, or strong membrane reactivity of constituent cells in varying proportions, without a transition between reactive and nonreactive cells. Results suggest that the majority of morphologically nondiagnostic atypical lesions are lobular, including those associated with DCIS. E-cadherin seems to be absent in most lobular lesions.

Evaluation of chemoresistance markers in women with epithelial ovarian carcinoma

OBJECTIVE

Preliminary studies have suggested that lung resistance protein (LRP), multidrug resistance protein (MRP), and p27 may be useful markers of chemoresistance. Our goal was to evaluate the expression of LRP, MRP, and p27 in normal ovaries and chemosensitive and chemoresistant ovarian carcinomas.

METHODS

Fourteen women with normal ovaries and fifty women with epithelial ovarian carcinoma who underwent cytoreductive surgery from 1996 through 1998 had specimens stained with immunocytochemistry for LRP, MRP, and p27. All women received paclitaxel/platinum-based chemotherapy. Twenty-nine women had a disease-free survival (DFS) of at least 12 months after completion of chemotherapy (sensitive) and 21 women had persistent disease during treatment (resistant).

RESULTS

Evaluation of LRP expression revealed significant differences between the normal ovaries and cancers in both the epithelial (57% vs 90%, P = 0.03) and stromal (86% vs 32%, P = 0.001) components. Evaluation of MRP expression revealed significant differences between normal ovaries and cancers in the epithelial component (7% vs 66%, P = 0.001) but not in the stromal component (14% vs 4%, P = 0.1). Evaluation of p27 revealed significant reductions in expression in cancers compared with normal ovaries for both the epithelial (90% vs 55%, P = 0.02) and stromal (88% vs 5%, P = 0.001) components. Comparison between the chemosensitive and chemoresistant groups revealed no significant differences in expression of LRP and MRP, in either the epithelial or stromal component, but significantly lower levels of p27 were expressed in the epithelial component of the chemoresistant group (P = 0.01).

CONCLUSIONS

The expression of LRP, MRP, and p27 is significantly different in ovarian cancers compared with normal ovaries. Low levels of p27 expression are associated with chemoresistance; however, LRP and MRP expression are not prognostic for chemosensitivity.

Immunohistochemical analysis of gynecologic tumors

Ancillary techniques such as immunohistochemistry (IHC) enable the surgical pathologist to extract additional information from fixed, deparaffinized tissue specimens and to provide data critical to optimal clinical management of the patient. In this review of applications of IHC to the analysis of gynecologic malignancies, the usefulness of immunohistochemical analysis of neoplasms of the cervix, endometrium, and ovary is summarized. In the uterine cervix, dysplasia is associated with qualitative and quantitative alterations in the expression of the Ki-67 antigen expression, as well as an ability to detect human papillomavirus. Endometrial endometrioid adenocarcinomas display a highly characteristic immunophenotype, with coexpression of cytokeratin and vimentin and demonstration of foci of high molecular weight cytokeratin expression; in addition, IHC analysis of estrogen and progesterone receptor and p53 expression can provide important prognostic information about this tumor. Stromal tumors of the endometrium may display a partial smooth muscle immunophenotype, but novel markers such as CD10 provide new tools for the identification of these tumors. The immunophenotypes of the normal ovarian surface epithelium (OSE) and corresponding tumors display significant overlap with, but important distinctions from, mesothelium, and important new markers such as the Wilms tumor gene product can prove useful in the identification of carcinomas of the OSE. Important prognostic markers for carcinomas of the OSE include the HER-2/neu gene product and p53, alterations of which can both be assessed by IHC techniques. Finally, the recent availability of markers of ovarian stroma, including Melan-A and inhibin-alpha, has provided a means for the positive identification of ovarian stromal tumors, which can manifest protean histological appearances.

Epstein-Barr virus, methotrexate, and lymphoma in patients with rheumatoid arthritis and primary Sjögren's syndrome: case series

OBJECTIVE

Rheumatoid arthritis (RA) and primary Sjögren's syndrome (SS) are associated with an increased risk of lymphoma. Epstein-Barr virus (EBV), a ubiquitous herpes virus, has been linked etiologically to lymphoma in patients with RA and primary SS. Recently, methotrexate (MTX) has also been linked to the development of these lymphomas. We investigated the frequency of EBV in lymphoma tissue of patients with RA and primary SS and the association of MTX with lymphomagenesis.

METHODS

Twenty-three patients with RA and 9 with primary SS with a history of lymphoma were identified by writing to all Arthritis Foundation member rheumatologists in Washington State. Formalin fixed, paraffin embedded tissue blocks were then requested from pathology laboratories. Lymph nodes from 5 RA patients without lymphoma were also studied. In situ hybridization using a biotinylated EBER-1 oligonucleotide probe was used to detect EBV in tissue sections. Positive and negative laboratory controls were used to ensure procedural integrity.

RESULTS

Specimens from 21 RA patients were obtained, with 2 subsequently excluded due to specimen quality. Specimens from 6 patients with primary SS were obtained. In situ hybridization for EBV was positive in 5/19 (26%) RA patients and 1/6 patients with primary SS. In the nonmalignant lymph nodes no patient showed EBV. One primary SS and 12 RA patients were known to be taking MTX at the time of lymphoma diagnosis. Of the EBV positive RA lymphoma patients, 4/5 were receiving MTX at the time of diagnosis. These results show that EBV is present in lymphoma tissue of some patients with RA and very few with primary SS.

CONCLUSION

EBV is over-represented in the lymphomas of patients with RA, but whether MTX plays a role in predisposing patients with RA and primary SS to the development of lymphoma, perhaps by influencing behavior of EBV, remains unclear.

Alterations in SPARC and VEGF immunoreactivity in epithelial ovarian cancer

OBJECTIVE

Secreted protein, acidic and rich in cysteine (SPARC), is a matricellular protein that modulates cell adhesion and growth. It is thought to play a decisive role in tissue remodeling and angiogenesis. Alterations in SPARC expression have been observed in a variety of solid tumors; however, no consistent pattern of deregulation has been characterized. Vascular endothelial growth factor (VEGF) has emerged as an important regulator of tumor neovascularization. Recent work has shown that SPARC modulates the mitogenic activity of VEGF in normal endothelium. While its role in malignant transformation remains elusive, SPARC may contribute to tumor propagation and invasion. This study examines the immunoreactivity of SPARC and VEGF associated with neoplastic transformation of the ovary.

METHODS

Immunostaining for VEGF and SPARC protein was performed on 62 archival specimens.

RESULTS

Fourteen normal ovaries and 48 ovarian carcinomas were evaluated. SPARC was detected in the stroma of 63% of ovarian carcinomas. In contrast, SPARC was observed in the stroma of only 29% of normal ovaries (P = 0.02). Furthermore, SPARC was limited in normal ovaries to premenopausal patients, juxtaposed either with vesiculated follicles or within the corpus luteum. VEGF was observed in 42% of ovarian carcinomas with immunoreactivity confined to tumor cells. The level of VEGF immunoreactivity was significantly higher in ovarian carcinoma compared to normal ovary epithelium (42 vs 7%, P = 0.02).

CONCLUSIONS

Immunoreactivity of SPARC and VEGF is heightened in association with ovarian carcinoma, with a distinct distribution of SPARC in the stroma of neoplastic ovaries and VEGF within tumor cells. No obvious pattern of coincident SPARC and VEGF immunoreactivity was detected. These results indicate the possibility of an aberration in the interaction that has been described in normal endothelium between SPARC and VEGF in association with malignant transformation.

Cytokeratin 8 immunostaining pattern and E-cadherin expression distinguish lobular from ductal breast carcinoma

Immunohistochemistry using antibodies to cytokeratin 8 can serve as a valuable diagnostic tool for the differentiation of lobular from ductal carcinomas of the breast. In contrast with ductal carcinomas, which exhibit a peripheral-predominant immunostaining pattern, adjacent tumor cells "molding" to each other, lobular carcinomas exhibit a ring-like perinuclear immunostaining pattern, creating a "bag of marbles" appearance with neighboring tumor cells. This immunostaining pattern is stable even in the tumors that otherwise do not exhibit characteristic histomorphologic features (i.e., solid or pleomorphic type of a lobular carcinoma) and tumors that mimic growth patterns characteristic of the respective other tumor type (i.e., targetoid or single-file growth pattern in a ductal carcinoma). Furthermore, we demonstrate that ductal carcinomas express E-cadherin in a similar peripheral-predominant immunostaining pattern (33/33 cases), while all 15 lobular carcinomas were negative for E-cadherin, suggesting a role for E-cadherin in the architectural organization of the cytoskeletal scaffolding within the tumor cells.

Detection of stromal invasion in breast cancer: the myoepithelial markers

Breast cancer can only be life threatening when it becomes invasive, at which point it carries potential for spreading and metastasis. Therefore, it is critical to distinguish invasive carcinomas (IC) from noninvasive lesions, the latter including ductal carcinoma in situ (DCIS) and benign breast lesions. While this distinction is usually made based on histologic evaluation alone, in a small but significant number of cases, accurate diagnosis may be impossible, particularly in the context of core needle biopsies. To this end, a number of immunohistochemical markers have been utilized to help establish the presence (or absence) of stromal invasion. The fact that the loss of the myoepithelial cell (MEC) layer is a hallmark of IC (but not DCIS) suggests the use of antibodies to MEC to distinguish IC from DCIS. However, these markers have a wide range of specificity and sensitivity, with the potential for problems in interpretation. The use of many of these markers is limited by high rates of 'false positive' or 'false negative' immunostaining. In this review, the biology of stromal invasion in breast carcinomas will be discussed, as well as the various myoepithelial markers, with emphasis on pitfalls related to their sensitivity and specificity in the detection of MECs in the breast. Finally, the authors will discuss diagnostically challenging breast lesions, which may require the use of MEC marker studies to reach a definitive diagnosis.

Salivary gland basal cell and canalicular adenomas: immunohistochemical demonstration of myoepithelial cell participation and morphogenetic considerations

OBJECTIVE

To evaluate cellular composition of salivary gland adenomas using 3 monoclonal antibodies that recognize a smooth muscle phenotype confirmed to be sensitive for myoepithelial differentiation.

DESIGN

Immunohistochemical evaluation of 25 salivary gland basal cell and canalicular adenomas.

SETTING

Archival pathology material from the files of Henry Ford Hospital, Detroit, Mich, and the University of California at San Francisco.

RESULTS

All basal cell adenoma variants exhibit some degree of myoepithelial cell participation with periductal, epithelioid, and spindled (stromal-like) morphologic structures. Only the canalicular adenomas, even if mixed with trabecular and solid patterns, are devoid of staining with these 3 antibodies, suggesting an adenoma composed exclusively of ductal luminal cells.

CONCLUSIONS

There is an overlapping histomorphologic and common cellular composition of the basal cell adenoma variants with other recognized adenomas, such as pleomorphic adenoma and myoepithelioma. Relative differentiation toward 3 cell phenotypes (ductal luminal, basal, and myoepithelial) and the character of extracellular matrix production in varying proportions by the neoplastic myoepithelial cells distinguishes the spectrum of salivary gland adenomas identified in current classification schemes.

HER-2/neu protein expression in breast cancer evaluated by immunohistochemistry. A study of interlaboratory agreement

Immunohistochemistry (IHC) is used commonly for evaluating HER-2/neu protein expression in breast cancer. Given the potential clinical importance of HER-2/neu status in patient management, interlaboratory variability in HER-2/neu IHC results in a matter of legitimate concern. We compared the results from 2 laboratories for HER-2/neu determined by IHC on paraffin sections of the same 100 consecutive invasive breast cancers. Both laboratories used the same primary antibody; however, different methods for heat-induced epitope retrieval (microwave or steam) and immunostaining (automated equipment from different manufacturers) and different scoring systems (positive-negative and 0-4+) were used. Slides were read in a blinded fashion and the results from the 2 laboratories were compared. Of the 93 cases evaluable in both laboratories, 24% were scored as HER-2/neu-positive at 1 laboratory, and 23% were scored as positive at the other. Complete concordance in categorization of HER-2/neu status between the 2 laboratories was achieved in 90 of 93 cases. Excellent interlaboratory agreement for HER-2/neu IHC was attained using the same primary antibody to HER-2/neu, even without standardization of assay method or scoring criteria. However, standardization of these parameters remains an important objective to optimize interlaboratory agreement.

Assessment of proliferative activity in breast cancer: MIB-1 immunohistochemistry versus mitotic figure count

The proliferative activity is one of the most important single prognostic parameters in breast cancer diagnosis and the time-honored measure of proliferative activity, the mitotic figure count, is an integral component of most combined prognostic scores. The detection of the cell cycle-specific antigens Ki-67, and the development of anti-Ki-67 antibodies, including the paraffin-reactive antibody MIB-1, have established immunohistochemical detection of cell cycle-specific antigens as a measure of proliferative activity in breast cancer diagnosis. The current study was performed to correlate mitotic figure counts with the proliferative activity as assessed by MIB-1 immunohistochemistry, taking into consideration the interobserver reliability of 5 pathologists in estimating mitotic figure counts. In 32 consecutive invasive ductal breast carcinomas, mitotic figure counts were performed independently by 5 pathologists. Mitotic activity was expressed as number of mitotic figures per 10 high-power fields and in a 3-tier score according to the Scarff Bloom Richardson system. Immunohistochemistry was performed using MIB-1 antibody, heat-induced epitope retrieval, and the standard avidin-biotin-immunoperoxidase method. MIB-1 immunohistochemistry was assessed in 3 representative 20x fields by semiquantitative estimation (% of tumor cells positive) and by image analysis (number of MIB-1-positive cells/mm2). We found a high degree of interobserver correlation among 4 experienced pathologists, in both mitotic figures per 10 high-power fields and the 3-tier scoring system. We observed significant, albeit weak, correlations between semiquantitative and quantitative MIB-1 immunohistochemistry and the number of mitotic figures per 10 high-power fields (r between .36 and .53), but this significance was lost in 3 of the 5 observers when mitotic activity was expressed in the 3-tier scoring system. This study confirms mitotic figure counting in the hands of experienced pathologists as a valid, reproducible means of assessing proliferative activity in routine breast cancer diagnosis. The statistically significant, albeit only weak, correlation with MIB-1 immunohistochemistry is in agreement with results obtained by others and suggests that MIB-1 immunohistochemistry cannot be translated by a simple conversion factor into combined prognostic scores to replace the time-honored mitotic figure counts.

RANTES production by cultured primate endometrial epithelial cells

PROBLEM

RANTES (regulated upon activation, normal T cell expressed and secreted), is a chemokine with monocyte, macrophage, T lymphocyte, and eosinophil attractant and activating activities. This mediator has been detected in the peritoneal fluid of patients with endometriosis and in cultures of stromal cells from human endometrial and endometriotic tissue. To determine if endometrial epithelial cells were also a potential source of this mediator, primate endometrial epithelial cells were cultured in vitro and the constitutive and stimulated production of RANTES in these cultures was measured.

METHOD OF STUDY

Uterine tissue was obtained from Macaca nemestrina monkeys and the endometrial epithelial cells were isolated and placed in culture for 24-72 hr. RANTES was measured in cell extracts and culture fluids by enzyme-linked immunosorbent assay (ELISA).

RESULTS

Constitute release of RANTES was low, ranging from 28-52 ng/mL but addition of interferon gamma (INF-gamma) or the combination of IFN-gamma and tumor necrosis factor alpha (TNF-alpha) produced a marked increase in RANTES production. The greatest release, which was nearly 500-fold greater than the basal level, was observed at 72 hr with the combined addition of TNF-alpha and INF-gamma. Nearly 90% of the stimulated RANTES was released into culture fluids, while cell associated RANTES was minimal constituting only 11.2% of the total.

CONCLUSION

These findings indicate that endometrial epithelial cells can produce and release RANTES. This chemokine may be an important attractant and activator of macrophages, T lymphocytes and/or eosinophils in the uterus during the reproductive cycle or implantation.

The myoepithelial immunophenotype in 135 benign and malignant salivary gland tumors other than pleomorphic adenoma

BACKGROUND

We have previously studied the immunoreactivity of 3 novel smooth muscle-specific proteins, alpha-smooth muscle actin, smooth muscle myosin heavy chains, and calponin, to assess myoepithelial differentiation in pleomorphic adenomas.

OBJECTIVE

To further expand our knowledge of myoepithelial differentiation in other benign and malignant salivary gland tumors.

DESIGN

Formalin-fixed paraffin sections of 135 salivary gland tumors with associated normal glands were stained with monoclonal antibodies using the avidin-biotin complex immunoperoxidase method and enzymatic and microwave heat-induced epitope retrieval.

RESULTS

In adenoid cystic carcinomas and epithelial-myoepithelial carcinomas, all 3 markers exclusively highlighted the myoepithelial cell components and the epithelial cells were entirely negative. No immunostaining was detected in canalicular adenomas, oncocytomas, Warthin tumors, acinic cell carcinomas, mucoepidermoid carcinomas, squamous cell carcinomas, and polymorphous low-grade adenocarcinomas. Salivary duct carcinomas and adenocarcinomas, not otherwise specified had a distinctive pattern of uniform periductal staining of reactive myofibroblastic cells, and in salivary duct carcinomas some ducts retained a peripheral immunoreactive myoepithelial cell layer.

CONCLUSION

Immunoreactivity for these 3 smooth muscle-specific proteins confirms the known neoplastic myoepithelial component of adenoid cystic carcinomas and epithelial-myoepithelial carcinomas. The consistently positive staining pattern in adenoid cystic carcinomas may be diagnostically useful in discriminating histologically similar but consistently negative polymorphous low-grade adenocarcinomas. Periductal linear staining in adenocarcinoma, not otherwise specified and salivary duct carcinomas is distinctive and appears to represent a tight cuff of myofibroblasts associated with the infiltrating glands.

Comparison of fluorescence in situ hybridization and immunohistochemistry for the evaluation of HER-2/neu in breast cancer

PURPOSE

To compare fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) in the determination of HER-2/neu status of breast cancers.

MATERIALS AND METHODS

FISH and IHC for HER-2/neu were performed on formalin-fixed paraffin sections of 100 consecutive invasive breast cancers. FISH was performed at Beth Israel Deaconess Medical Center, Boston, MA, using the Oncor/Ventana INFORM kit (Ventana Medical Systems, Tucson, AZ; formerly sold by Oncor, Inc, Gaithersburg, MD) in a laboratory certified as proficient in this procedure. IHC was performed at PhenoPath Laboratories, Seattle, WA, using a polyclonal antibody to the HER-2/neu protein. FISH and IHC were analyzed in a blinded fashion, and the results were then compared. Procedure and interpretation times and reagent costs for FISH and IHC were also compared.

RESULTS

HER-2/neu was amplified by FISH in 26% of cases, and 23% were HER-2/neu-positive by IHC. FISH and IHC were both assessable in 90 cases. Concordance between FISH and IHC results was seen in 82 of these cases (91%, P <.001). The FISH procedure required more technologist time and more interpretation time per case for the pathologist than IHC. Reagent costs were substantially higher for FISH than for IHC.

CONCLUSION

There is a high level of correlation between FISH and IHC in the evaluation of HER-2/neu status of breast cancers using formalin-fixed paraffin-embedded specimens. Although the choice of which assay to use should be left for individual laboratories to make based on technical and economic considerations, our results may make it difficult to justify the routine use of FISH for determination of HER-2/neu status in breast cancer.

Specificity of HercepTest in determining HER-2/neu status of breast cancers using the United States Food and Drug Administration-approved scoring system

PURPOSE

To evaluate the specificity of the HercepTest for Immunoenzymatic Staining (Dako Corp, Carpinteria, CA) for determining HER-2/neu protein expression in breast cancer.

MATERIALS AND METHODS

Forty-eight invasive breast cancers previously found to be HER-2/neu-negative by two different immunohistochemical (IHC) assays and not amplified for the HER-2/neu gene by fluorescence in situ hybridization were studied using the HercepTest kit. HercepTest was performed according to the manufacturer's guidelines, and the results were scored on a 0 to 3+ scale using the United States Food and Drug Administration (FDA)-approved grading system. In this system, cases scored as 2+ or 3+ are considered HER-2/neu-positive.

RESULTS

Among these 48 cases, the IHC score using the FDA-approved scoring system was 0 in four cases (8.3%), 1+ in 16 (33.3%), 2+ in 21 (43.8%), and 3+ in seven (14.6%). Therefore, 58.4% of these cases were categorized as HER-2/neu-positive, and the specificity of the HercepTest kit for HER-2/neu expression was 41.6%. However, with the use of a modified scoring system that took into account the level of staining of nonneoplastic epithelium, the specificity increased to 93.2%.

CONCLUSION

Our results indicate that the HercepTest kit, when used in accordance with the manufacturer's guidelines and the FDA-approved scoring system, results in a large proportion of breast cancers being categorized as positive for HER-2/neu protein expression and that many of these seem to be false-positives. Consideration of the level of staining of nonneoplastic epithelium resulted in improved specificity. The current FDA-approved scoring system for HercepTest results should be reevaluated before its widespread use in clinical practice.

Abnormal expression of the cystic fibrosis transmembrane regulator in chronic sinusitis in cystic fibrosis and non-cystic fibrosis patients

Cystic fibrosis (CF) patients commonly suffer from chronic sinusitis. Mutations of a single gene, the cystic fibrosis transmembrane conductance regulator (CFTR) gene, have been associated with CF. Functional CFTR protein is localized to the apical cell membrane, while dysfunctional CFTR is commonly found in the cytoplasm. We undertook a preliminary immunocytochemical study of CFTR subcellular localization in CF and non-CF pediatric and adult patients using a newly developed murine monoclonal antibody, TAM. Immunostaining was evaluated for subcellular localization (cytoplasmic versus membranous) and for epithelial layer (basal versus luminal). Analysis of the predominant CFTR distribution patterns demonstrated significant differences in adult versus pediatric groups independent of whether the latter were CF or non-CF (p<.0001 and p<.008, respectively), and no significant difference between the 2 pediatric groups (p = .70). This suggests that the pathophysiology of pediatric sinusitis differs from that of adult sinusitis at the level of secretion production.

Distribution of calponin and smooth muscle myosin heavy chain in fine-needle aspiration biopsies of the breast

The cell types that may be present in any fine-needle aspiration biopsy (FNAB) of breast include epithelial cells (EC), myoepithelial cells (MEC), bipolar stromal cells (BSC), vascular pericytes/endothelial cells (VPEC), and adipose cells (AC). The recognition of most of these benign cellular elements in aspirates of the breast is relatively straightforward, based on distinct cytomorphologic criteria. However, there is controversy regarding the recognition of MEC because BSC are often referred to as MEC by cytopathologists. It is important to identify MEC in breast aspirates, because their presence has been associated with benign epithelial proliferations. In this study we used immunocytochemical methods on archival cytology slides with antibodies specific for MEC, calponin, and smooth muscle myosin heavy chain (SMMHC), to determine the distribution of MEC in FNAB of the breast and to ascertain the distribution of MEC in in situ and invasive carcinomas. Fifteen benign FNABS of breast and corresponding tissue biopsies were obtained along with 10 malignant FNABS and corresponding excisional breast biopsies from 1989-1993. Calponin and SMMHC antibodies were used on archival alcohol-fixed Papanicolaou-stained direct smears as well as the corresponding tissue sections. The distribution and pattern of positive immunostaining with both antibodies were recorded on the benign elements and the carcinomas for both cytologic and histologic slides. Benign breast tissues demonstrated strong continuous immunostaining for calponin and SMMHC of MEC. The interlobular stromal cells as well as intralobular stromal cells showed no immunostaining with either antibody. In cytologic preparations, MEC staining with calponin and SMMHC appeared as spindle cells between epithelial cells or along the edges of the epithelial groups. The bipolar stromal cells did not stain with either antibody. The tissues with DCIS (ductal carcinoma in situ) often showed the presence of MEC with strong calponin immunostaining, but sometimes the immunostaining was discontinuous or entirely absent around markedly dilated ducts. The SMMHC antibody was invariably negative, with architectural DCIS in dilated ducts. Two cases of DCIS with prominent periductal fibrosis or inflammation were positive for calponin, but the periductal stromal cells were calponin- and SMMHC-negative. Invasive carcinoma was negative for both calponin and SMMHC, but areas of DCIS were often positive in a discontinuous pattern. In conclusion, 1) Benign cellular elements from breast tissue FNAB showed strong continuous decoration of MEC with both calponin and SMMHC. Vascular pericytes and vascular smooth muscle were positive for both antibodies, but these cells were not observed in the FNAB. Benign proliferative epithelium showed no local increase in MEC with either antibody. Bipolar stromal cells in tissue and smears did not stain for MEC antibodies. 2) BSC did not correspond morphologically to MEC, and were not decorated with calponin or SMMHC. 3) Calponin-positive MEC were commonly associated with in situ ductal lesions, although they may at times have been discontinuous or absent entirely. DCIS may be recognized in FNAB by the presence of calponin-positive MEC associated with tumor cell groups. 4) Invasive carcinomas were invariably negative for MEC with these antibodies.

Monitoring gene expression profile changes in ovarian carcinomas using cDNA microarray

The development of cancer is the result of a series of molecular changes occurring in the cell. These events lead to changes in the expression level of numerous genes that result in different phenotypic characteristics of tumors. In this report we describe the assembly and utilization of a 5766 member cDNA microarray to study the differences in gene expression between normal and neoplastic human ovarian tissues. Several genes that may have biological relevance in the process of ovarian carcinogenesis have been identified through this approach. Analyzing the results of microarray hybridizations may provides new leads for tumor diagnosis and intervention.

Myoepithelial cells and basal lamina in poorly differentiated in situ duct carcinoma of the breast. An immunocytochemical study

A retrospective study was made of 38 selected brest tumours with a poorly differentiated in situ duct component. These were classified on haematoxylin and eosin (H&E) as ductal carcinoma in situ (DCIS; 10 cases), DCIS with invasion (17 cases) and DCIS with features suggestive of for stromal invasion (11 cases). The last were these lesions composed of neoplastic ducts with irregular outlines and a myoepithelial layer that was not clearly evident or large neoplastic ducts growing close together or surrounded by inflammatory desmoplastic stroma. Cases of DCIS involving areas of sclerosing adenosis were included in this category. Consecutive sections obtained from each case were studied with a panel of antibodies against myoepithelial cells (alpha smooth muscle actin and calponin) and basal lamina (BL) components (laminin and type IV collagen). It was found that in situ lesions showed well-formed basal lamina and/or an evident myoepithelial layer. These features were lacking in the invasive areas. Nine of the 11 cases with suggestive features of stromal invasion were reclassified as invasive duct carcinoma (5 cases)and DCIS (4 cases), according to the absence or presence of a continuous myoepithelial layer and/or basal lamina. In 2 such cases immunohistochemistry yielded equivocal results and the label "suggestive of invasion" was therefore pertinent. Immunohistochemistry facilitates the diagnosis of breast DCIS; myoepithelial and basal lamina markers are useful in differentiating microinvasive from in situ ductal carcinomas of the breast.

Thyroid transcription factor-1: immunohistochemical evaluation in pulmonary neuroendocrine tumors

Thyroid transcription factor-1 (TTF-1), a nuclear transcription protein selectively expressed in the thyroid, the diencephalon, and respiratory epithelium, is expressed in more than 90% of pulmonary small cell carcinomas (SCLCs) and in almost 75% of pulmonary non-small cell carcinomas (NSCLCs), but it is absent in typical pulmonary carcinoids (TCs). Therefore, it was thought that SCLC and NSCLC might share a common lineage, different from that of TC. TTF-1 expression in atypical pulmonary carcinoids (ACs) and large-cell neuroendocrine carcinomas (LCNECs) was not studied previously. We examined TTF-1 expression in 51 TCs, 9 ACs, 8 LCNECs, and 21 SCLCs with use of formalin-fixed material and heat-induced epitope retrieval. TTF-1 expression was seen in 18 (35%) of 51 TCs, all of the 9 ACs, 6 (75%) of the 8 LCNECs, and 20 (95%) of the 21 SCLCs. These results reinforce earlier findings of the excellent sensitivity of TTF-1 for SCLC, and they show similar sensitivity for AC and LCNEC, but they argue against the hypothesis that SCLC and TC are of different cell lineages. The ubiquity of TTF-1 expression in pulmonary NECs demonstrated in this study also argues against its use in their subclassification.

Complete chromogen separation and analysis in double immunohistochemical stains using Photoshop-based image analysis

Simultaneous detection of two different antigens on paraffin-embedded and frozen tissues can be accomplished by double immunohistochemistry. However, many double chromogen systems suffer from signal overlap, precluding definite signal quantification. To separate and quantitatively analyze the different chromogens, we imported images into a Macintosh computer using a CCD camera attached to a diagnostic microscope and used Photoshop software for the recognition, selection, and separation of colors. We show here that Photoshop-based image analysis allows complete separation of chromogens not only on the basis of their RGB spectral characteristics, but also on the basis of information concerning saturation, hue, and luminosity intrinsic to the digitized images. We demonstrate that Photoshop-based image analysis provides superior results compared to color separation using bandpass filters. Quantification of the individual chromogens is then provided by Photoshop using the Histogram command, which supplies information on the luminosity (corresponding to gray levels of black-and-white images) and on the number of pixels as a measure of spatial distribution. (J Histochem Cytochem 47:119-125, 1999)

Expression of androgen receptors in nasopharyngeal angiofibroma: an immunohistochemical study of 24 cases

Angiofibromas are uncommon benign tumors that typically occur in the lateral portion of the nasopharynx of adolescent boys. Numerous reports showed indirect evidence for the presence of sex-hormone receptors, i.e., androgen (AR), estrogen (ER), and progesterone (PR) receptors, in these tumors. The goal of the current study was to show direct evidence of sex hormone receptor expression in angiofibromas with use of sensitive immunocytochemical techniques and to document which cell populations express the receptor. Twenty-four nasopharyngeal angiofibromas were obtained from archived tissue, and immunocytochemical studies were performed with antibodies to AR, PR, and ER. Positive stromal and endothelial nuclear immunostaining, implying the presence of ARs, was seen in 18 (75%) of 24 cases, whereas 2 (8.3%) of 24 cases were positive with antibodies to PR. None of the 24 cases examined was positive with antibodies to ER. These results provide the first direct evidence for the presence of ARs in angiofibromas, which might help to explain the unique clinicopathologic features of these tumors.

Tenosynovial giant cell tumors: evidence for a desmin-positive dendritic cell subpopulation

Diffuse tenosynovial giant cell tumor (DGCT) could present as a large intra-articular mass (pigmented villonodular synovitis, or PVNS) or as an extraarticular mass, which might be confused with a sarcoma, particularly when growth is destructive and giant cells are few. Prompted by a DGCT in which a subpopulation of cells was desmin positive and in which an erroneous diagnosis of myosarcoma was made, we analyzed the frequency of desmin, myogenin, MyoD1, and muscle-specific actin immunoreactivity in 45 well-characterized GCTs. We also analyzed a subset of these cases with antibodies to smooth muscle actin, as well as macrophage, follicular dendritic cell, extrafollicular dendritic cell, and dermal dendrocyte-associated antigens. Sections from 45 cases of formalin-fixed GCTs (22 DGCTs, 13 cases of PVNS, and 10 localized GCTs) were immunostained for desmin, myogenin, MyoD1, and muscle-specific actin. The eight cases that showed the largest number of desmin-positive cells were immunostained for smooth muscle actin, CD45, CD68, CD21, CD35, cytokeratin 8, and Factor XIIIa. Desmin-positive cells were seen in 20 (43%) of 45 cases: 10 (43%) of 22 DGCTs, 5 (38%) of 13 cases of PVNS, and 5 (50%) of 10 localized GCTs. In contrast, none were positive for any of the other muscle-associated proteins. In almost all of the cases, the desmin-positive cells were large and dendriform, with long processes that interdigitated between adjacent round cells. Desmin immunoreactivity was found in almost 50% of all GCTs, in the absence of positivity for other muscle markers. Desmin immunoreactivity in GCT seemed to be confined to a variably sized subpopulation of large dendritic cells whose exact identity remains uncertain.

Immunophenotype of ovarian cancer as predictor of clinical outcome: evaluation at primary surgery and second-look procedure

OBJECTIVE

This study was undertaken to evaluate whether immunophenotyping of advanced epithelial ovarian cancer could predict response to initial chemotherapy and whether tumor immunophenotype changed after chemotherapy.

STUDY DESIGN

Fifty-four patients with stage III and IV ovarian cancer, treated at the University of Washington Medical Center, had pathology specimens evaluated. A subset of 23 patients also had specimens from a secondary surgery evaluated. Using immunocytochemistry, tumors were immunostained for overexpression of c-erb-B-2, epidermal growth factor receptor (EGFR), p53, and expression of the Ki67-defined antigen (a marker of cellular proliferation), tumor necrosis factor alpha (TNFalpha), estrogen receptor (ER), progesterone receptor (PR), and P-glycoprotein (P170, a marker of multidrug resistance). Twenty-four patients had a good response to chemotherapy (defined as a negative, or microscopically positive second look), and 30 had a poor response (defined as grossly positive second look or progressive disease).

RESULTS

Comparison of tumor markers from the initial and the secondary surgeries revealed that the only significant change was in the Ki67-defined cell proliferation rate, which showed a marked reduction in those with a good response to chemotherapy (P = 0.002). Comparison of tumor markers at initial surgery between good and poor responders revealed a correlation with p53 expression. Good responders were less likely to have p53 overexpression compared to poor responders, and this result approached significance (P = 0.058). Comparison of tumor markers at secondary surgery revealed a significant reduction in Ki67-defined cell proliferation rate in good responders compared to poor responders (P = 0.01). No significant differences were found between good and poor responders for the other tumor markers evaluated.

CONCLUSIONS

The only tumor markers to predict for response to chemotherapy were p53 at initial surgery (P = 0.058) and Ki67 indices at secondary surgery (P = 0.001). Expression of steroid hormone receptors, TNFalpha, and P-glycoprotein and overexpression of c-erb-B-2 or EGFR are not associated with chemoresistance.

Oncogene expression: long-term compared with short-term survival in patients with advanced epithelial ovarian cancer

OBJECTIVE

To determine if oncogene overexpression in patients with advanced epithelial ovarian cancer correlates with survival.

METHODS

Twenty-two women with stage III ovarian cancer, observed for a median of 66 (range 48-204) months were compared with 30 with a median survival of 18 (range 2-28) months. Using immunocytochemistry, tumors were immunostained for overexpression of p53, c-erb-B-2, and epidermal growth factor receptor and were evaluated quantitatively for expression of estrogen receptor, progesterone receptor, and Ki-67 antigen, a marker of cellular proliferation.

RESULTS

The median age of long-term survivors was 52 (range 30-76) years compared with 55 (range 36-80) years for short-term survivors. Optimal cytoreduction was achieved in 11 of the 22 long-term survivors compared with seven of the 30 short-term survivors, a significant difference (P=.05). The average level of Ki-67 expression was 43% in long-term survivors and 64% in short-term survivors (P=.007). Overexpression of p53 was seen in 54% of long-term survivors and 80% of short-term survivors (P=.05). A combination of Ki-67 level of 50% or greater plus p53 overexpression was seen in 22% of long-term survivors compared with 68% of short-term survivors (P=.005). Epidermal growth factor receptor, c-erb-B-2, estrogen receptor, and progesterone receptor statuses did not differ significantly between the two groups.

CONCLUSION

Markers that did not correlate with survival included the hormone receptors, estrogen receptor and progesterone receptor, and the oncogenes, c-erb-B-2 and epidermal growth factor receptor. Long-term survivors with advanced ovarian cancer were more likely to have had an optimal cytoreduction and lower levels of Ki-67 antigen expression and were less likely to overexpress p53 than were short-term survivors.