CD56 Reactivity in Small Cell Carcinoma of the Uterine Cervix

Immunosensitivity and specificity of insulinoma-associated protein 1 (INSM1) for neuroendocrine neoplasms of the uterine cervix

OBJECTIVE

Previously, we reported that insulinoma-associated protein 1 (INSM1) immunohistochemistry (IHC) showed high sensitivity for neuroendocrine carcinoma of the uterine cervix and was an effective method for histopathological diagnosis, but that its specificity remained to be verified. Therefore, the aim was to verify the specificity of INSM1 IHC for a large number of non-neuroendocrine neoplasia (NEN) of the cervix.

METHODS

RNA sequences were performed for cell lines of small cell carcinoma (TCYIK), squamous cell carcinoma (SiHa), and adenocarcinoma (HeLa). A total of 104 cases of formalin-fixed and paraffin-embedded specimens, 16 cases of cervical NEN and 88 cases of cervical non-NEN, were evaluated immunohistochemically for conventional neuroendocrine markers and INSM1. All processes without antigen retrieval were performed by an automated IHC system.

RESULTS

The transcripts per million levels of INSM1 in RNA sequences were 1505 in TCYIK, 0 in SiHa, and HeLa. INSM1 immunoreactivity was shown only in the TCYIK. Immunohistochemical results showed that 15 cases of cervical NEN showed positive for INSM1; the positivity score of the tumor cell population and the stain strength for INSM1 were high. Two of the 88 cases of cervical non-NENs were positive for INSM1 in one case each of typical adenocarcinoma and squamous cell carcinoma. The sensitivity of INSM1 for cervical NEN was 94%; specificity, 98%; the positive predictive value, 88%; and the negative predictive value, 99%.

CONCLUSION

INSM1 is an adjunctive diagnostic method with excellent specificity and sensitivity for diagnosing cervical NEN. Higher specificity can be obtained if morphological evaluation is also performed.

INSM1 Is Less Sensitive But More Specific Than Synaptophysin in Gynecologic High-grade Neuroendocrine Carcinomas: An Immunohistochemical Study of 75 Cases With Specificity Test and Literature Review

Insulinoma-associated protein 1 (INSM1) has emerged as a promising diagnostic marker for high-grade neuroendocrine carcinomas (HGNECs); however, it is controversial whether INSM1 is more sensitive than conventional markers chromogranin, synaptophysin, and CD56. Here, we investigated immunohistochemical expression of INSM1 in 75 gynecologic HGNECs using full tissue sections (30 small-cell carcinomas [SmCCs], 34 large-cell neuroendocrine carcinomas [LCNECs], and 11 mixed SmCC and LCNEC), with specificity analysis in 422 gynecologic non-neuroendocrine tumors (410 in tissue microarrays and 12 full sections) and comparison with conventional neuroendocrine markers for their sensitivity and specificity. Positive INSM1 staining was seen in 69 (92%) HGNECs, whereas chromogranin, synaptophysin, and CD56 staining was seen in 61 (81%), 72 (96%), and 44 (69%) tumors, respectively (INSM1 vs. chromogranin, P=0.09; INSM1 vs. synaptophysin, P=0.4942; and INSM1 vs. CD56, P<0.001). The mean percentage of INSM1-positive tumor cells was 54% (median: 60%, range: 0% to 100%), similar to chromogranin (58%, P=0.2903) and higher than CD56 (30%, P=0.00001) but significantly lower than synaptophysin (89%, P<0.00001). INSM1 showed no staining difference among SmCCs, LCNECs, and mixed SmCC-LCNECs. Among the 422 non-neuroendocrine tumors, positive staining was seen in 5% tumors for INSM1, 18% for chromogranin, 19% for synaptophysin, and 25% for CD56. Our study indicates that INSM1 is a highly specific marker (95% specificity) for gynecologic HGNECs with high sensitivity (92%), but it is less sensitive than synaptophysin (96% sensitivity). INSM1 is more specific than chromogranin, synaptophysin, and CD56 for gynecologic HGNECs. Our literature review reveals that INSM1 has consistently (the same antibody clone A8 used for all reported studies) shown higher or similar sensitivity to chromogranin (for all 3 chromogranin antibody clones LK2H10, DAK-A3, DAKO polyclonal); however, whether INSM1 is more or less sensitive than synaptophysin or CD56 for HGNECs is highly dependent on the antibody clones used for synaptophysin (clones MRQ-40 and SNP88 showing higher sensitivity than clones 27G12 and DAK-SYNAP) or CD56 (clones CD564, MRQ-42, and MRQ-54 showing higher sensitivity than clones 123C3D5, 1B6, and Leu243).

Histology-specific FGFR2 alterations and FGFR2-TACC2 fusion in mixed adenoid cystic and neuroendocrine small cell carcinoma of the uterine cervix

Neuroendocrine small cell carcinoma of the uterine cervix portends a dismal prognosis with limited treatment options. Rarely, tumors of mixed-lineage appear in gynecologic malignancies. Here, we report a 77-year-old woman who presented with complete uterine prolapse and 4-month history of vaginal bleeding. Histopathologic evaluation revealed a mixed adenoid cystic carcinoma and neuroendocrine small cell carcinoma of the uterine cervix. The tumor was PD-L1 and HPV 35 positive. The patient was treated with up-front surgery and adjuvant radiation. Independent, histology-specific alterations in FGFR2 and a FGFR2-TACC2 fusion were identified. Progression of disease occurred within 6 months for which she received chemotherapy and immunotherapy. However, the patient expired within a year. We comprehensively review how screening for and targeting of FGFR alterations in recurrent and metastatic cervical cancer might serve as a touchstone for future treatment regimens.

Updates and management algorithm for neuroendocrine tumors of the uterine cervix

Neuroendocrine carcinomas of the cervix account for less than 2% of all invasive cervical cancers and are classified as low-grade (carcinoid, atypical carcinoid tumor) or high-grade (known as small- and large-cell) neuroendocrine carcinomas. There are increasing data showing that cervical neuroendocrine carcinomas may be associated with the human papillomavirus (HPV), especially HPV18, and most will stain positive for p16. Immunohistochemistry markers such as synaptophysin and CD56 are the most sensitive markers. Although there are no commonly associated mutations, PIK3CA, KRAS, and TP53 are the most frequently found mutations in neuroendocrine tumors. Neuroendocrine cervical carcinomas are exceedingly aggressive tumors with a high tendency for nodal involvement and distant metastases. Age, lymph node metastases, smoking, pure small-cell histology, and tumor size are independent prognostic factors. Overall, the 5-year survival rate is 36% and the median overall survival ranges between 22 and 25 months. Treatment options are often extrapolated from small-cell lung cancer and limited retrospective studies. The preferred treatment is a multimodal approach of surgery, chemoradiation, and systemic chemotherapy. The most common chemotherapy regimen used as initial therapy is a combination of cisplatin and etoposide. In the setting of recurrent disease, a combination of topotecan, paclitaxel, and bevacizumab has demonstrated favorable outcomes. Multicenter tumor registries, such as the Neuroendocrine Cervical Tumor Registry (NeCTuR), are an opportunity to evaluate patterns of disease treatment and oncologic outcomes.

Large cell neuroendocrine carcinoma of the endometrium: A case report and literature review

OBJECTIVE

To report a case and review published cases of large cell neuroendocrine carcinoma (LCNEC) of the endometrium.

CASE REPORT

A 51-year-old female presented with postmenopausal bleeding and a palpable pelvic mass. An endometrial biopsy showed a malignant mixed Mullerian tumor (MMMT). Suboptimal debulking surgery was performed. The final pathology revealed stage IVB endometrial LCNEC. Post-operative adjuvant chemotherapy with cisplatin and etoposide was administered. Two months after discontinuing adjuvant chemotherapy, salvage chemotherapy with cisplatin and ifosfamide was administered due to tumor progression; however, obstructive ileus was noted 2 months later. A segmental small bowel resection and palliative colostomy were performed. She died secondary to a post-operative infection 8 days after the operation.

CONCLUSION

Endometrial LCNEC is a rare but aggressive disease. If diagnosed, combined therapies, including staging surgery, following by adjuvant radiotherapy and chemotherapy, should be performed.

Tissue-based Immunohistochemical Biomarker Accuracy in the Diagnosis of Malignant Glandular Lesions of the Uterine Cervix: A Systematic Review of the Literature and Meta-Analysis

Immunohistochemistry is widely used to support a pathology diagnosis of cervical adenocarcinoma despite the absence of a systematic review and meta-analysis of the published data. This systematic review and meta-analysis was performed to investigate the sensitivity and specificity of immunohistochemistry biomarkers in the tissue-based diagnosis of cervical adenocarcinoma histotypes compared with normal endocervix and benign glandular lesions. The systematic review and meta-analysis used a PICOT framework and QUADAS-2 to evaluate the quality of included studies. The literature search spanned 40 years and ended June 30, 2015. Abstracts of identified records were independently screened by 2 of the authors who then conducted a full-text review of selected articles. Sensitivity and specificity of immunohistochemistry expression in malignant glandular lesions of the cervix classified per WHO 2003 compared with 5 benign comparators (normal/benign endocervix, and benign endocervical, endometrioid, gastric, and mesonephric lesions) were calculated. Of 902 abstracts screened, 154 articles were selected for full review. Twenty-five articles with results for 36 biomarkers were included. The only biomarker with enough studies for a meta-analysis was p16 and the definition of positive p16 staining among them was variable. Nevertheless, any positive p16 expression was sensitive, ranging from 0.94 to 0.98 with narrow confidence intervals (CIs), for adenocarcinoma in situ (AIS) and mucinous adenocarcinomas in comparison with normal/benign endocervix and benign endocervical and endometrioid lesions. Specificity for AIS and mucinous adenocarcinomas was also high with narrow CIs compared with benign endocervical lesions. The specificity was high for AIS, 0.99 (0.24, 1.0), and mucinous adenocarcinoma, 0.95 (0.52, 1.0), compared with normal/benign endocervix but with wider CIs, and low with very wide CIs compared with benign endometrioid lesions: 0.31 (0.00, 0.99) and 0.34 (0.00, 0.99), respectively. Results from single studies showed that p16, p16/Ki67 dual stain, ProExC, CEA, ESA, HIK1083, Claudin 18, and ER loss in perilesional stromal cells were useful with high (≥0.75) sensitivity and specificity estimates in ≥1 malignant versus benign comparisons. None of the biomarkers had highly useful sensitivity and specificity estimates for AIS, mucinous adenocarcinomas, or minimal deviation adenocarcinoma/gastric adenocarcinoma compared with benign gastric or mesonephric lesions or for mesonephric carcinoma compared with normal/benign endocervix, benign endocervical, endometrial, or mesonephric lesions. Any expression of p16 supports a diagnosis of AIS and mucinous adenocarcinomas in comparison with normal/benign endocervix and benign endocervical lesions. The majority of studies did not separate mosaic/focal p16 staining from diffuse staining as a distinct pattern of p16 overexpression and this may have contributed to the poor performance of p16 in distinguishing AIS and mucinous adenocarcinomas from benign endometrioid lesions. Single studies support further investigation of 8 additional biomarkers that have highly useful sensitivity and specificity estimates for ≥1 malignant glandular lesions compared with ≥1 of the 5 benign comparators.

Contribution of Human papillomavirus in neuroendocrine tumors from a series of 10,575 invasive cervical cancer cases

Aims

Neuroendocrine tumors (NET) of the cervix are rare tumors with a very aggressive course. The human papillomavirus (HPV) has been linked to its etiology. The objective of this study is to describe HPV prevalence and genotype distribution of NET.

Methods and Results

Forty-nine tumors with histological neuroendocrine features were identified among 10,575 invasive cervical cancer (ICC) cases from an international study. HPV DNA detection was done using SPF10/DEIA /LiPA₂₅ system. Immunohistochemical (IHC) staining for neuroendocrine markers (chromogranin A, synaptophysin, CD56) and for p16^INK4a as a surrogate for HPV transforming infection was performed. In 13 samples with negative IHC for all 3 neuroendocrine markers studied, it was possible to conduct electron microscopy (EM).

NET represented 0.5% of the total ICC series and HPV was detected in 42 out of 49 samples (85.7%, 95%CI:72.8%,94.1%). HPV16 was the predominant type (54.8%), followed by HPV18 (40.5%). p16^INK4a overexpression was observed in 38/44 cases (86.4%). Neuroendocrine IHC markers could be demonstrated in 24/37 (64.9%) cases. EM identified neuroendocrine granules in 8 samples with negative IHC markers.

Conclusions

Our data confirms the association of cervical NET with HPV and p16^INK4a overexpression. Specifically, HPV16 and 18 accounted together for over 95% of the HPV positive cases. Current HPV vaccines could largely prevent these aggressive tumors.

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Neuroendocrine tumors of the cervix are rare tumors with aggressive course.

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We identified HPV DNA in 85.7% of neuroendocrine tumors analyzed.

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HPV16 and 18 accounted together for over 95% of the HPV DNA positive cases.

CD56 (Neural Cell Adhesion Molecule) Expression in Ovarian Carcinomas: Association With High-Grade and Advanced Stage But Not With Neuroendocrine Differentiation

OBJECTIVE

Neural cell adhesion molecule (CD56) has been proposed as a potential marker for neuroendocrine differentiation in carcinomas, together with synaptophysin and chromogranin A. However, CD56 immunoreactivity by itself can be found in a broad variety of tumors, including ovarian neoplasms. CD56 has recently been suggested as a potential target for antibody-based therapy. However, for ovarian carcinoma, there is only limited data available regarding the pattern of CD56 immunoreactivity, coexpression of neuroendocrine markers, and correlation with histological types and clinical parameters.

METHODS

In our study, we therefore evaluated CD56 staining by immunohistochemistry on a tissue micrroarray with 206 ovarian carcinomas, including 151 high-grade serous, 7 low-grade serous, 32 endometrioid, 11 clear cell, 5 mucinous, as well as 33 atypically proliferating serous tumors/serous borderline tumors.

RESULTS

At least focal CD56 immunoreactivity was observed in 65% of carcinomas of all histological types. Moderate staining with at least 10% positive cells was found in 44 (28%) high-grade serous carcinomas (HGSOCs), 2 (29%) low-grade serous and 3(9%) endometrioid carcinomas. Strong immunoreactivity was limited to 10 (7%) HGSOCs. There was no correlation with the expression of chromogranin or synaptophysin. Serous borderline tumors showed only weak and focal staining in 11 (33%). Expression of CD56 overall was significantly associated with high-grade and advanced stage. In the subgroup of HGSOCs, CD56 expression was associated with reduced overall survival (median 30 vs. 47 months, P = 0.039, log rank, univariate analysis).

CONCLUSIONS

CD56 (neural cell adhesion molecule) is frequently expressed in ovarian carcinomas and is significantly associated with HGSOC and advanced tumor stage. Due to its lack of correlation with neuroendocrine differentiation, CD56 expression is of limited diagnostic value, but may rather serve as a marker for tumor progression or as a potential therapeutic target.

Neuroendrocrine tumors of the uterine cervix: A therapeutic challenge for gynecologic oncologists

Neuroendocrine tumors (NETs) are aggressive diseases developing from neuroendocrine cells that most frequently involve the gastro-entero-pancreatic tract and the lung, but more rarely are found in almost all body tissues. Limited biological and clinical data are currently available for NETs in uncommon sites, such as female genital tract. NETs represent 0.9% to 1.5% of the tumors of the uterine cervix. They are more likely to have lymph-vascular space invasion and lymph node involvement, and to develop local and distant relapses when compared with the mostly common cervical squamous cell carcinomas or adenocarcinomas. Positive immunostaining for synaptophysin, chromogranin, CD56, and neuron-specific enolase is often detected in cervical NETs . The most recent editions of the World Health Organization Classification of Gynecologic Tract tumors grouped cervical carcinoid tumor and atypical carcinoid tumor into low-grade NETs and cervical small cell neuroendocrine carcinoma and large cell neuroendocrine carcinoma into high-grade NETs. High-risk HPV DNA is detected in almost all cervical high-grade NETs. No treatment guidelines, based on prospective, well-designed clinical trials, are currently available due to the rarity of these tumors. Many authors have reported different multimodality approaches, mainly derived from NETs of the lung. These usually consist in radical hysterectomy followed by adjuvant chemotherapy or concurrent chemoradiation for early stage disease, definitive concurrent chemoradiation sometimes preceded by neoadjuvant chemotherapy and followed by adjuvant chemotherapy for locally advanced disease, and palliative chemotherapy for metastatic disease. In this systematic review, we address the histologic classification of cervical NETs, analyze their pathogenesis and overall prognosis, and evaluate the different treatment modalities described in the literature, in order to offer a possible algorithm that may help the clinicians in diagnosing and treating patients with these uncommon and aggressive malignancies.

A new marker, insulinoma-associated protein 1 (INSM1), for high-grade neuroendocrine carcinoma of the uterine cervix: Analysis of 37 cases

OBJECTIVE

High-grade neuroendocrine carcinoma of uterine cervix (HGNCUC) has been recognized as a highly malignant tumor. Therapeutic strategy specific to neuroendocrine (NE) tumors needs to be considered, but some cases wouldn't allow simple final diagnoses. Insulinoma-associated protein 1 (INSM1), which is a zinc-finger transcription factor related to NE differentiation, is frequently expressed in NE tumors. We investigated the association between INSM1 and HGNCUC, and the possibility of INSM1 as a useful NE marker.

METHODS

Thirty-seven cases of formalin-fixed and paraffin-embedded HGNCUCs were evaluated immunohistochemically for conventional NE markers and INSM1. We also surveyed polymerase chain reactions and examined the frequency and the genotype of human papillomavirus (HPV) infections.

RESULTS

In HGNCUC, chromogranin A, synaptophysin and neural cell adhesion molecule (NCAM) were expressed in 86%, 86% and 68%, respectively. In addition, INSM1 was detected in 95%. Positivity for INSM1 was clearly evaluated histologically, because the intensity of nuclear staining on positive cells was high and nonspecific reactions were minimal. In uni- and multivariate analyses of prognostic factors on stage I and II surgical cases, the association between INSM1 expression and prognosis was insignificant. We confirmed 72% of 29 examined cases had high risk HPV infections (type 16, 14%; type 18, 86%).

CONCLUSIONS

This study has clarified that INSM1 is closely related to the development of HGNCUC, and a useful new NE marker in conducting its correct and rapid diagnosis.

Neuroendocrine Carcinoma of the Cervix: Review of a Series of Cases and Correlation With Outcome

Introduction Neuroendocrine carcinoma (NEC) of the cervix is associated with a poor prognosis despite multimodal treatment. The correct diagnosis of this tumor type is imperative to provide clinicians and patients with prognostic information and ensure that appropriate treatment is provided. Methods A clinicopathological study was undertaken on all cervical tumors registered as NEC with the West Midlands Cancer Intelligence Unit between January 1, 1998 and December 31, 2009. Of the 45 cases diagnosed during the study period, the tumor samples of 41 cases were traced, anonymized, and then independently reviewed by 2 gynecological pathologists. Results The review confirmed 31/41 (78%) cases to be NEC, which overall, represented 1.3% of all the cervical cancers registered in the West Midlands over the period of the study. In the correct histological context, synaptophysin was the most sensitive and specific positive immunohistochemical marker of NEC differentiation. The cases that on review were confirmed as NEC had a significantly worse outcome than the non-NEC cases: median survival for NEC cases was 33.3 months versus 315.0 months for the non-NEC cases, P = .013. Conclusions Histological review of a series of NECs has shown significantly reduced survival in those patients with confirmed NEC in comparison with those patients where a diagnosis of NEC was not confirmed. We propose morphological and immunohistochemical criteria for the diagnosis of cervical NEC; and discourage unqualified use of the term "small cell carcinoma" as this does not accurately convey the diagnosis of SCNEC. We urge pathologists to use the 2014 World Health Organization classification when reporting these tumors.

Neuroendocrine Tumors of the Female Reproductive Tract: A Literature Review

Neuroendocrine tumors of the female reproductive tract are a heterogeneous group of neoplasms that display various histologic findings and biologic behaviors. In this review, the classification and clinicopathologic characteristics of neuroendocrine tumors of the female reproductive tract are described. Differential diagnoses are discussed, especially for non-neuroendocrine tumors showing high-grade nuclei with neuroendocrine differentiation. This review also discusses recent advances in our pathogenetic understanding of these disorders.

Use of immunohistochemistry in the diagnosis of miscellaneous and metastatic tumors of the uterine corpus and cervix

Uncommon tumors in the uterus present diagnostic challenges. In some cases, the tumor subtype is usually seen outside the gynecologic tract and the possibility of a uterine primary is not considered. In other cases, histologic overlap with more common uterine tumors leads to potential misdiagnosis. Finally, metastatic carcinoma may involve the uterus and cervix. Rarely, symptoms related to the uterine metastasis may precede diagnosis of an extrauterine primary. Without the proper clinical context, the possibility of a missed diagnosis is increased. One must first be aware of these possibilities, but immunoperoxidase studies are often necessary to confirm the diagnosis. In this review, unusual and metastatic tumors involving the uterine corpus and cervix and immunoperoxidase studies used to diagnosis such tumors are discussed.

Neuroendocrine tumors of the gynecologic tract: select topics

Tumors of the diffuse neuroendocrine cell system (DNES) may arise in any component of the gynecologic tract, including the vulva, vagina, cervix, endometrium, and ovary. Overall such tumors in the gynecologic tract are rare, constituting only 2% of gynecologic cancers, comprising a spectrum of tumors of variable biologic potential. Due to the rarity of such tumors, pathologists experience may be limited and these may present diagnostic challenges. Currently the nomenclature employed is still that of the pulmonary classification systems, carcinoid, atypical carcinoid, small and large cell neuroendocrine carcinoma that broadly correlates to low/grade 1, intermediate/grade 2, and high grade/grade 3 of the WHO gastroenteropancreatic neuroendocrine tumors classification. Furthermore in keeping with the lung, proliferative rate is assessed based on mitotic index rather than Ki-67 staining. In this review we cover select neuroendocrine tumors of the gynecologic tract.

Extrapulmonary small cell carcinoma: a clinicopathological study with identification of potential diagnostic mimics

AIMS

To evaluate the clinicopathological features of small cell carcinoma arising outside the lung.

METHODS AND RESULTS

Thirty-seven cases with a pathology diagnosis of extrapulmonary small cell carcinoma (EPSCC) were selected. The clinical notes were reviewed and tumour blocks were selected for a fresh haematoxylin and eosin (H&E) section and immunohistochemical stains. The most common tumour locations were cervix and bladder. Twenty-five cases (68%) were finally diagnosed as EPSCC, nine of which were found with coexisting non small cell carcinoma. Two cases (5%) were diagnosed as large cell neuroendocrine carcinoma (LCNEC) of the cervix. The remainder was classified as 10 poorly differentiated carcinomas (PDCs) (27%). Positive staining for thyroid transcription factor 1 (TTF-1) was noted in nine cases of EPSCC and in none of the cases of PDC (P = 0.034). Synaptophysin immunoreactivity was found in 20 cases of EPSCC and two cases of PDC with neuroendocrine differentiation (P = 0.002), as well as two cases of LCNEC. 34βE12 was positive in eight cases of SCC and two cases of PDC.

CONCLUSIONS

Based on this series, EPSCC may be overdiagnosed. Immunohistochemistry for TTF-1, used in combination with synaptophysin, may help to discriminate EPSCC from PDC.

A clinicopathological aspect of primary small-cell carcinoma of the uterine cervix: a single-centre study of 25 cases

AIMS

Small-cell carcinoma is a variant of poorly differentiated neuroendocrine carcinoma. Primary small-cell carcinoma of the cervix (SCCC) is recognised as a rare and aggressive malignant tumour with poor prognosis. In this study, the authors report 25 Chinese cases of SCCC, with a particular focus on their clinical and pathological characteristics.

MATERIAL AND METHODS

The records of 25 patients from 4075 Chinese patients with cervical cancer were collected and reviewed, including the patients' age, initial symptoms, cervical tumour size, International Federation of Gynaecology and Obstetrics clinical stage, lymph-node metastasis, treatments and follow-up results. Immunohistochemical detection was performed for cytokeratin, epithelial membrane antigen, neuron-specific enolase (NSE), synaptophysin (Syn), chromogranin A (CgA), neuronal cell adhesion molecules (CD56), thyroid transcriptional factor-1 and S100 protein (S100).

RESULTS

The median age of 25 patients with SCCC was 43.7 years. The most common symptom was abnormal vaginal bleeding. Histologically, there were 19 'homogenous' SCCC samples and six samples of SCCC mixed with adenocarcinoma. The proportion of SCCC samples with positive immunoreactivity were 100.0% for NSE, 96.0% for Syn, 68.0% for CD56, 76.0% for CgA, 40.0% for thyroid transcriptional factor-1, 84.0% for epithelial membrane antigen, 68.0% for cytokeratin and 8.0% for S100, respectively. Every patient received one to three types of treatments, including surgery, chemotherapy and radiotherapy. The median survival time of patients was 20.9 months after diagnosis.

CONCLUSION

The higher proportion of positive labelling of Syn, CD56, CgA, and NSE in SCCC implicated that they are valuably applied in a differential diagnosis of the malignancy. The patients with SCCC receive one to three types of therapies, including surgery, chemotherapy and radiotherapy, and have a poor prognosis.

An immunohistochemical study of cervical neuroendocrine carcinomas: Neoplasms that are commonly TTF1 positive and which may express CK20 and P63

Cervical small cell neuroendocrine carcinoma (SCNEC) and large cell neuroendocrine carcinoma (LCNEC) are uncommon but highly aggressive neoplasms. From a diagnostic point of view, there may be problems both in distinguishing these from other neoplasms and in confirming a cervical origin. This is important as management is critically dependent on the correct histologic diagnosis. We undertook a detailed immunohistochemical analysis of a relatively large series of primary cervical SCNEC (n=13) and LCNEC (n=8). Cases were stained with AE1/3, chromogranin, CD56, synaptophysin, PGP9.5, TTF1, p16, p63, CK7, CK20, neurofilament, and CD99. CK20 and neurofilament staining was undertaken to investigate whether some of these neoplasms might exhibit a Merkel cell immunophenotype and CD99 staining to assess whether there is immunohistochemical overlap with neoplasms in the Ewing family of tumors (EFT). For all markers, staining was classified as negative, 1+ (<10% cells immunoreactive), 2+ (10 to 50% cells immunoreactive), or 3+ (>50% cells immunoreactive). Eleven and 6 SCNEC and LCNEC, respectively were positive with AE1/3. Chromogranin, CD56, synaptophysin, and PGP9.5 were positive in 11, 19, 19, and 9 cases, respectively. Altogether 15 cases (71%) (11 SCNEC, 4 LCNEC) exhibited nuclear positivity, often diffuse, with TTF1. All but 1 case was diffusely positive with p16. p63 was positive in 9 cases, including 5 with diffuse nuclear immunoreactivity. Ten and 4 neoplasms were positive with CK7 and CK20, respectively. Neurofilament was positive in 7 tumors. The 4 neoplasms that were CK20 positive were stained with the monoclonal antibody CM2B4, generated against an antigenic epitope on the Merkel cell polyomavirus T antigen; all were negative. CD99 was positive in 6 cases. In 2 cases, adjacent foci of adenocarcinoma in situ (AIS) contained scattered individual chromogranin positive cells, raising the possibility that some cervical neuroendocrine carcinomas arise from neuroendocrine cells in AIS. Four of 13 cases of pure AIS also contained scattered chromogranin positive cells. Our results illustrate that a proportion of cervical neuroendocrine carcinomas are negative with broad spectrum cytokeratins and some of the commonly used neuroendocrine markers. TTF1 positivity is extremely common and may be a useful marker of a neuroendocrine carcinoma. It is of no value in exclusion of a pulmonary primary. p16 is almost always positive in cervical neuroendocrine carcinomas, possibly owing to an association with oncogenic human papillomavirus, although other mechanisms of expression are also possible. Cervical neuroendocrine carcinomas may be p63 positive, illustrating that this marker is not specific for squamous differentiation. CK20 and neurofilament positivity in some cervical neuroendocrine carcinomas is in keeping with a Merkel cell immunophenotype, similar to that described in SCNECs in other organs. However, the absence of staining with CM2B4 argues against a true Merkel cell tumor. CD99 staining in a cervical neuroendocrine carcinoma should not result in misdiagnosis as a neoplasm in the Ewing family of tumors.

Small cell carcinomas and large cell neuroendocrine carcinomas of the endometrium and cervix: polypoid tumors and those arising in polyps may have a favorable prognosis

We report 5 polypoid high-grade neuroendocrine carcinomas of the uterus, 2 small cell carcinomas of the endometrium, and 3 large cell neuroendocrine carcinomas, 2 from the cervix and 1 from the endometrium. The 2 small cell carcinomas of the endometrium arose from and were confined to endometrial polyps, one of which also showed foci of endometrioid adenocarcinoma. The myometrium was free of tumor, despite extensive sampling. The 3 large cell neuroendocrine carcinomas, 2 from the cervix and 1 from the endometrium, were polypoid but did not originate in polyps. Two of these tumors infiltrated myometrium, and one did not. The age of the 5 patients ranged from 25 to 66 years (mean age, 43 years). Four patients presented with vaginal bleeding. One pregnant woman had the largest polypoid tumor discovered during a routine gynecologic examination. Tumor sizes ranged from 2.7 to 10 cm. All 5 patients were treated by radical hysterectomy and 4 received adjuvant chemotherapy. Only 2 patient had pelvic lymph node metastasis. All patients are alive and disease-free from 9 months to 7 years after treatment (mean survival, 47 months). All 5 tumors labeled with chromogranin and synaptophysin and 4 with CD56. Two small cell carcinomas and 2 large cell neuroendocrine carcinomas accumulated p53 protein. Two small cell carcinomas and 2 large cell neuroendocrine carcinomas expressed p16. Our findings suggest that stage of disease and a polypoid gross feature are the best predictors for outcome in small cell carcinomas and large cell neuroendocrine carcinomas of the uterus.

Polysialylated NCAM represses E-cadherin-mediated cell-cell adhesion in pancreatic tumor cells

BACKGROUND & AIMS

Inhibition of cell-cell adhesion between epithelial cells represents an early step during tumor metastasis. Down-regulation or perturbation of E-cadherin-mediated adherens junctions is an essential requirement in this process.

METHODS

The interaction between polysialylated neural cell adhesion molecule (PSA-NCAM) and the E-cadherin adhesion complex was studied by coimmunoprecipitation assays. The presence of PSA-NCAM was correlated with tumor invasion by using cell-cell aggregation and cell migration assays. The importance of polysialic acid (PSA) in the interaction of NCAM with E-cadherin and inhibition of cell-cell adhesion was confirmed by enzymatic removal of PSA from NCAM and down-regulation of PSA-transferases by siRNA.

RESULTS

Expression of oncogenic K-Ras(V12) in pancreatic carcinoma cells resulted in induction of PSA-NCAM expression and reduced E-cadherin-mediated cellular adhesion. The association of PSA-NCAM with the E-cadherin adhesion complex correlated with decreased cell-cell aggregation and elevated cell migration of pancreatic carcinoma cells. Enzymatic removal of PSA from NCAM or reduction of polysialyltransferase expression led to reduced association between NCAM and E-cadherin and subsequently increased E-cadherin-mediated cell-cell aggregation and reduced cell migration.

CONCLUSIONS

Our data suggest the induction of PSA-NCAM by oncogenic K-Ras as a novel molecular mechanism by which E-cadherin-mediated cellular adhesion is reduced and dissemination of tumor cells is facilitated.

Application of immunohistochemistry to gynecologic pathology

CONTEXT

A large variety of tumors and lesions arise in the female genital tract. Although the majority of these can be correctly recognized on routine hematoxylin-eosin-stained slides, occasional cases present a diagnostic challenge. Immunohistochemical stains are extremely useful in resolving many of these problematic cases. As the knowledge in this area is constantly expanding, it is useful to have this updated information in a review form for easy access.

OBJECTIVE

To present our current knowledge of immunohistochemistry of the lesions of the female genital tract in a readily accessible form.

DATA SOURCES

The review is based on previously published articles on this topic.

CONCLUSIONS

Immunohistochemical stains help in reaching a conclusive diagnosis in a variety of problematic lesions seen in gynecologic pathology. As in any other system, immunohistochemical findings need to be interpreted in light of the clinical history and morphologic findings.

Combined large cell neuroendocrine and endometrioid carcinoma of the endometrium

We present the surgical and pathological findings and follow-up of 5 women diagnosed with combined endometrioid and high-grade neuroendocrine carcinoma of large cell type (LCNEC) arising in the endometrium. The mean age of the women was 75 years (range, 50-88 years). Of the 5 tumors, 4 formed polypoid endometrial masses associated with extensive lymphovascular involvement of the myometrium by neoplastic cells. A single endometrial tumor was formed by LCNEC alone, and 4 tumors were composite with varying proportions formed by endometrioid (4/5) and small cell neuroendocrine carcinoma (1/5). In all 5 LCNEC tumor components, an insular growth pattern was noted, whereas a diffuse (solid) pattern was found in 4 tumors, a trabecular in 2, and rosettes/pseudorosettes in another 2. In all 5 tumors, the LCNEC tumor components were labeled with neuron-specific enolase (NSE). Four tumors were reactive for chromogranin A, CAM 5.2, and p53. Three tumors were labeled for AE1/AE3, CD56 (NCAM), p16, and cytokeratin 7. Synaptophysin was reactive in 2 tumors, and CD117 was found in only a single tumor. Of the 3 endometrioid tumor components examined, all were reactive for NSE. Two tumors were reactive for p16 and p53, 1 for CD56, but none for synaptophysin orchromogranin A. We conclude that LCNEC of the endometrium is a distinct clinicopathological entity with a poor prognosis irrespective of stage. The gross and histomorphological features are often suggestive, but confirmation requires immunoperoxidases, including NSE, synaptophysin, chromogranin A, p16, and p53. Combined endometrioid and high-grade LCNEC possess more characteristics of a type II than a type I endometrial carcinoma.

Ovarian nonsmall cell neuroendocrine carcinoma: a clinicopathologic and immunohistochemical study of 11 cases

Nonsmall cell neuroendocrine carcinoma (NSCNEC) of the ovary is a rare and aggressive tumor commonly associated with other surface epithelial and germ cell neoplasms. In this study, we present the clinicopathologic and immunohistochemical features of 11 such cases seen at The University of Texas M.D. Anderson Cancer Center in a 16-year period (1990 to 2005). Patients ranged in age from 22 to 63 years (mean 46.7). The most common presentation was abdominal/pelvic pain (6 cases), followed by ascites (2 cases), pelvic mass, vaginal bleeding, and abdominal bloating (1 case each). Tumors were mostly unilateral, cystic, or solid/cystic and ranged in size from 5 to 26 cm (mean 16.2). In 8 cases, NSCNEC was associated with other epithelial neoplasms, including mucinous neoplasms of low malignant potential, mucinous carcinoma, endometrioid carcinoma, mixed endometrioid and mucinous carcinoma, and a high-grade carcinoma, not otherwise specified. In 2 cases, the tumor was associated with a mature cystic teratoma; one of them also containing an invasive moderately differentiated adenocarcinoma. A single case was associated with a benign ovarian cyst. The latter case had a dermoid cyst in the contralateral ovary. NSCNEC represented anywhere from 10% to 90% of the ovarian tumor. Microscopically, the neuroendocrine component was usually composed of large and/or intermediate oval to round cells. In 2 cases, the intermediate cells were intermixed with small cells. Three cases had also spindle cells. The neoplastic cells were mostly arranged in a solid pattern, nests, or trabeculae. All tumors had a brisk mitotic activity. Immunoperoxidase studies for keratin cocktail, cytokeratin (CK) 7, CK20, CAM 5.2, chromogranin A, synaptophysin, NSE, CD56, and c-kit were performed and the cases stained as follows: keratin cocktail 6/6, CK7 4/5, CK20 3/5, CAM 5.2 3/3, chromogranin A 8/11, synaptophysin 9/9, NSE 1/1, CD56 4/8, and c-kit 5/7. According to the International Federation of Gynecology and Obstetrics staging system, 4 cases were stage I tumors, 3 cases were stage III tumors, and 4 cases were stage IV tumors. Seven patients were treated with total abdominal hysterectomy and bilateral salpingo-oophorectomy followed by chemotherapy. One patient had a bilateral salpingo-oophorectomy with omentectomy and appendectomy followed by chemotherapy; 1 patient had a total abdominal hysterectomy with right salpingo-oophorectomy followed by chemotherapy; one had a bilateral salpingo-oophorectomy followed by chemotherapy, and one had a right salpingo-oophorectomy with appendectomy followed by chemotherapy. Five patients died of disease at 2, 3, 9, 20, and 36 months. One patient is alive with disease at 8 months and 5 are alive without evidence of disease at 11, 28, 37, 66, and 68 months. Four of 5 patients who died of disease had either stage III or IV tumors and 3 of 5 patients who are alive without evidence of disease have stage I tumors. In summary, ovarian NSCNEC is an aggressive tumor with a tendency to present at advanced stage and cause death within a mean of 17 months after diagnosis; however, some patients, particularly those with stage I disease and/or those who have received platinum-based therapy, may have a more favorable prognosis.

Immunohistochemistry as a diagnostic aid in cervical pathology

As with biopsies from other sites in the female genital tract, immunohistochemistry is now being increasingly used in cervical pathology as an aid to diagnosis. In this review, I discuss applications of immunohistochemistry in diagnostic cervical pathology with a particular focus on recent developments. It is emphasised that immunohistochemistry is to be used as an adjunct to routine morphological examination and that no marker is totally specific or sensitive for a given lesion. Although much of this review focuses on glandular lesions, the value of markers, such as MIB1 and p16, in the assessment of pre-invasive cervical squamous lesions is discussed. In the broad field of cervical glandular lesions, topics covered include: the value of markers such as MIB1, p16 and bcl-2 in distinguishing adenocarcinoma in situ and glandular dysplasia from benign mimics; markers of mesonephric lesions, including CD10; markers of value in the diagnosis of minimal deviation adenocarcinoma, such as HIK1083; markers of value in distinguishing metastatic cervical adenocarcinoma in the ovary from primary ovarian endometrioid or mucinous adenocarcinoma. Rarely ectopic prostatic tissue occurs in the cervix, which can be confirmed by positive staining with prostatic markers. A panel of markers, comprising oestrogen receptor, vimentin, monoclonal carcinoembryonic antigen and p16, is of value in distinguishing between a cervical adenocarcinoma and an endometrial adenocarcinoma of endometrioid type. Markers of use in the diagnosis of cervical neuroendocrine neoplasms, including small cell and large cell neuroendocrine carcinoma, are discussed. It is stressed that small cell neuroendocrine carcinomas may be negative with most of the commonly used neuroendocrine markers and this does not preclude the diagnosis. p63, a useful marker of squamous neoplasms within the cervix, is of value in distinguishing small cell neuroendocrine carcinoma (p63 negative) from small cell squamous carcinoma (p63 positive) and in confirming that a poorly differentiated carcinoma is squamous in type.

p16-Positive Small Cell Neuroendocrine Carcinoma of the Endometrium

We report herein a small cell neuroendocrine carcinoma of the endometrium that extended to the cervix and showed strong immunohistochemical staining for p16. The p16 staining raised the possibility of a human papillomavirus (HPV)-related tumor, because in the cervix, a positive p16 immunohistochemical stain is presumptive evidence of HPV. However, the current case was HPV negative. We discuss the molecular pathogenesis of non-HPV-related increased p16 expression.

p16, p14, p53, and Cyclin D1 Expression and HPV Analysis in Small Cell Carcinomas of the Uterine Cervix

Small cell carcinomas (SmCCs) of the uterine cervix are rare tumors. The knowledge regarding protein expression of several checkpoint candidates of cell cycle regulation is limited. Surgically treated SmCCs were selected from our files for immunohistochemical staining (neuroendocrine markers, p53, p16, p14, and cyclin D1). Polymerase chain reaction analysis, using general primers, was performed for human papillomavirus analysis. Nine of 677 tumors (1.3%) were classified as SmCCs after Grimelius staining (8/9 tumors positive) and immunohistochemical reaction against neurone-specific enolase, chromogranin A, synaptophysin (7/9 positive tumors), and CD 56 (8/9 positive tumors). All specimens were positive for at least two of the above. Two SmCCs were p53 positive and one case was p14 positive. Cyclin D1 staining was completely negative. All cases showed strong nuclear and/or cytoplasmic p16-immunostaining. Seven tumors represented human papillomavirus positivity for high-risk types. Four patients died of the tumor after a median time of 36.7 months (range, 15-56 months), representing a 5-year survival rate of 56%. The results suggest that p16 is up-regulated or accumulated in the SmCCs of the uterine cervix, probably caused by infection with human papillomavirus. p14 inactivation is of high prevalence in SmCCs and detection rate of p53 is similar to other histologic types of cervical carcinomas.