Detection of Human Papillomavirus DNA and Expression of p16, Rb, and p53 Proteins in Small Cell Carcinomas of the Uterine Cervix

Advancements in the Understanding of Small-Cell Neuroendocrine Cervical Cancer: Where We Stand and What Lies Ahead

Small-cell neuroendocrine cervical carcinoma (SCNCC) is a rare yet aggressive gynecological malignancy associated with dismal clinical outcomes. Its rarity has led to a limited number of retrospective studies and an absence of prospective research, posing significant challenges for evidence-based treatment approaches. As a result, most gynecologic oncology centers have limited experience with this tumor, emphasizing the urgent need for a comprehensive review and summary. This article systematically reviews the pathogenesis, immunohistochemical and molecular characteristics, prognostic factors, and clinical management of gynecologic SCNCC. We specifically focused on reviewing the distinct genomic characteristics of SCNCC identified via next-generation sequencing technologies, including loss of heterozygosity (LOH), somatic mutations, structural variations (SVs), and microRNA alterations. The identification of these actionable genomic events offers promise for discovering new molecular targets for drug development and enhancing therapeutic outcomes. Additionally, we delve deeper into key clinical challenges, such as determining the optimal treatment modality between chemoradiation and surgery for International Federation of Gynecology and Obstetrics (FIGO) stage I phase patients within a precision stratification framework, as well as the role of targeted therapy within the homologous recombination (HR) pathway, immune checkpoint inhibitors (ICIs), and prophylactic cranial irradiation (PCI) in the management of SCNCC. Finally, we anticipate the utilization of multiple SCNCC models, including cancer tissue-originated spheroid (CTOS) lines and patient-derived xenografts (PDXs), to decipher driver events and develop individualized therapeutic strategies for clinical application.

The association between human papillomavirus and bladder cancer: Evidence from meta-analysis and two-sample mendelian randomization

INTRODUCTION

Bladder cancer (BCa) is the 10th most common type of cancer worldwide, and human papillomavirus (HPV) is the most common sexually transmitted infection. However, the relationship between HPV infection and the risk of BCa is still controversial and inconclusive.

METHODS

This systematic review and meta-analysis were conducted following the PRISMA 2020 reporting guideline. This study searched four bibliographic databases with no language limitation. The databases included PubMed (Medline), EMBASE, Cochrane Library, and Web of Science. Studies evaluating the interaction between HPV infection and the risk of BCa from inception through May 21, 2022, were identified and used in this study. This study estimated the overall and type-specific HPV prevalence and 95% confidence intervals (95% CI) using Random Effects models and Fixed Effects models. In addition, this study also calculated the pooled odds ratio and pooled risk ratio with 95% CI to assess the effect of HPV infection on the risk and prognosis of bladder cancer. Two-sample mendelian randomization (MR) study using genetic variants associated with HPV E7 protein as instrumental variables were also conducted.

RESULTS

This study retrieved 80 articles from the four bibliographic databases. Of the total, 27 were case-control studies, and 53 were cross-sectional studies. The results showed that the prevalence of HPV was 16% (95% CI: 11%-21%) among the BCa patients, most of which were HPV-16 (5.99% [95% CI: 3.03%-9.69%]) and HPV-18 (3.68% [95% CI: 1.72%-6.16%]) subtypes. However, the study found that the prevalence varied by region, detection method, BCa histological type, and sample source. A significantly increased risk of BCa was shown for the positivity of overall HPV (odds ratio [OR], 3.35 [95% CI: 1.75-6.43]), which was also influenced by study region, detection method, histological type, and sample source. In addition, the study found that HPV infection was significantly associated with the progression of BCa (RR, 1.73 [95% CI: 1.39-2.15]). The two-sample MR analysis found that both HPV 16 and 18 E7 protein exposure increased the risk of BCa (HPV 16 E7 protein: IVW OR per unit increase in protein level = 1.0004 [95% CI: 1.0002-1.0006]; p = 0.0011; HPV 18 E7 protein: IVW OR per unit increase in protein level = 1.0003 [95% CI: 1.0001-1.0005]; p = 0.0089).

CONCLUSION

In conclusion, HPV may play a role in bladder carcinogenesis and contribute to a worse prognosis for patients with BCa. Therefore, it is necessary for people, especially men, to get vaccinated for HPV vaccination to prevent bladder cancer.

The prognostic impact of the immune microenvironment in small-cell neuroendocrine carcinoma of the uterine cervix: PD-L1 and immune cell subtypes

Background

We investigate the correlation between programmed cell death-ligand 1 (PD-L1) and tumor-associated immune cell (TAIC) density in small-cell neuroendocrine carcinoma of the uterine cervix (SCNEC) and their correlation with clinicopathologic features.

Methods

PD-L1 and mismatch repair protein (MMR) expression in cancer cells and the density of TAIC were evaluated by immunohistochemistry in 89 SCNEC patients. The combined positive score (CPS), tumor proportion score (TPS), and immune cell score (ICS) of PD-L1 were measured, along with their correlation with clinicopathologic features in SCNEC patients using statistical analyses.

Results

CPS of PD-L1 ≥ 1 was seen in 68.5% of patients, positive TPS and ICS of PD-L1 were detected in 59.6% and 33.7% of patients, respectively. PD-L1CPS was higher in tumor-infiltrating immune cells (r = 0.387, p = 0.001) and positively correlated with programmed cell death-1 and forkhead box P3 + regulatory T cell (FOXP3 + Treg) infiltration (r = 0.443, p < 0.001; r = 0.532, p < 0.001). There was no statistical correlation between PD-L1 and MMR status. PD-L1CPS and PD-L1ICS positivity were independent prognostic factors, correlating with a favorable survival (HR (95%CI) = 0.363(0.139–0.950), p = 0.039 and HR (95% CI) = 0.199(0.050–0.802), p = 0.023, respectively). PD-L1ICS positivity was an independent indicator of recurrence in SCNEC patients and associated with better disease-free survival (HR (95% CI) = 0.124(0.036–0425), p = 0.001). TAIC and MMR levels had no statistical impact on survival results.

Conclusions

PD-L1 positivity was seen in over half of SCNEC tumors. It may work synergistically with FOXP3 + Treg and other infiltrating immune cells to support an adaptive immune response. PD-L1 positivity may be a favorable prognostic factor in SCNEC.

Clinicopathological Analysis of Neuroendocrine Carcinoma of the Uterine Cervix: A Single-Institution Retrospective Review of 9 Cases

Aim

To evaluate the clinicopathological features affecting the recurrence and survival of 9 cases of neuroendocrine cancer of the cervix.

Method

We retrospectively analyzed 9 cervical neuroendocrine cancer cases identified among 453 cervical cancer patients between 2004 and 2021 at Akdeniz University Gynecological Oncology Outpatient Clinic. Kaplan–Meier survival analysis was used for progression-free survival (PFS) and overall survival (OS). Mathematical functions of mean, standard deviation, median, Min–Max values, and frequencies were used for descriptive statistics. The categorical data were expressed in numbers and percentages (%).

Results

Nine patients with neuroendocrine histological subtype were selected out of 453 patients diagnosed with cervical cancer (1.98%). The average overall survival time of the patients was 26 months. The 5-year survival rate was 53.3%, while the PFS was 62.5%. The most common subtype was small cell neuroendocrine cancer. Tumours were mostly locally advanced at the time of diagnosis. 3 patients' stage was 1b2, while 4 patients were 2b, 1 patient was 3c2r, and 1 patient was 4b. All tumours showed the immunohistochemical staining properties of neuroendocrine cancer. The main treatment modality applied to our patients was surgery + adjuvant CRT. The most used chemotherapeutic agents were cisplatin/carboplatin and etoposide. Recurrence was found in 3 cases, including 5 deaths.

Conclusion

Neuroendocrine tumour of the cervix is a rare subtype with a poor prognosis. Unfortunately, there is not yet a standard treatment protocol due to the limited number of comparative studies of surgery, chemotherapy, and radiotherapy based treatment schemes.

Expression and Significance of HPV16 E6/E7 mRNAs in the Bronchial Brush and TBNA Cells of Patients With Small Cell Lung Cancer

BACKGROUND AND OBJECTIVE

Small cell lung cancer (SCLC) is characterized by rapid growth, strong invasion, and early metastasis. However, the cause of its occurrence remains unclear. High-risk HPV infection is closely related to the occurrence of non-small cell lung cancer and cervical small cell neuroendocrine carcinoma.

METHODS

The expression levels of E6 mRNA and E7 mRNA in HPV16 were detected by qRT-PCR in the bronchial brushing and transbronchial needle aspiration (TBNA) of 310 patients with lung cancer and with benign lung diseases. To make the design of this experiment scientific and reasonable, the expression levels in lung squamous cell carcinoma were taken as positive controls, while those in benign cells were taken as negative controls.

RESULTS

The expression levels of E6 mRNA and E7 mRNA in SCLC group were significantly higher than those in benign cell group and slight higher than those in squamous cell carcinoma group. The expression levels of E6 mRNA and E7 mRNA in the central type of SCLC were significantly higher than those in the peripheral type of SCLC.

CONCLUSIONS

We speculate that the occurrence of some small cell carcinoma is the same as that of some squamous cell carcinoma, which is closely related to HPV16 infection. The overexpression of E6 mRNA and E7 mRNA is in some benign lesion cells, which may be related to HPV transient infection.

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.

Human Papillomavirus Infection, p16INK4a Expression and Genetic Alterations in Vietnamese Cervical Neuroendocrine Cancer

Neuroendocrine cervical cancer is a rare subtype of cervical cancer with a highly aggressive malignancy. This study was conducted to analyse the human papillomavirus (HPV) infection and molecular abnormalities in Vietnamese neuroendocrine carcinomas of the uterine cervix. HPV genotyping and p53 mutations were examined using polymerase chain reaction (PCR)-based direct sequencing. Mutations of epidermal growth factor receptor (EGFR), Kirsten rat sarcoma (KRAS), neuroblastoma RAS viral oncogene homolog (NRAS) and v-Raf murine sarcoma viral oncogene homolog B (BRAF) were identified using commercial kits. Four high-risk HPV genotypes were identified in 26 (86.7%) out of a total of 30 tumours. The prevalence of HPV 16, 18, 31 and 45 was 20.0%, 50.0%, 20.0% and 36.7%, respectively. Overexpression of p16^INK4a was observed in 93.3% of cases and was significantly correlated with high-risk HPV infections. Furthermore, p53 and NRAS mutations were detected in five (16.7%) and one (3.3%) cases, respectively, whereas no EGFR, KRAS or BRAF mutations were observed. These results demonstrate that high-risk HPV infection may be an important oncogenic factor for the development and progression of cervical neuroendocrine carcinoma.

Human Papillomavirus-Associated Oropharyngeal High-Grade Neuroendocrine Carcinoma in an Adolescent: Case Report and Review of Literature

Oropharyngeal small cell carcinomas (OPSmCC) are rare with only few case reports and case series published in the literature. More recently, an association of these tumors with human papillomavirus (HPV) infection has been detected. However, unlike oropharyngeal squamous cell carcinomas which have a better outcome when associated with HPV, OPSmCC exhibit an aggressive behavior. In this article, we report a case of tonsillar carcinoma arising in a 14-year-old boy that was associated with HPV infection. The tumor exhibited morphologic features of small cell carcinoma with no overt squamous differentiation. Yet, by immunohistochemistry, it showed diffuse and strong co-expression of both squamous and neuroendocrine markers. In addition, we present the clinicopathologic features of all the cases of OPSmCC reported in the literature for which p16 and/or HPV testing have been done.

Next-generation Sequencing Reveals Recurrent Somatic Mutations in Small Cell Neuroendocrine Carcinoma of the Uterine Cervix

Small cell neuroendocrine carcinoma (SCNEC) of the uterine cervix is a rare but extremely aggressive tumor. While high-risk human papillomavirus (HPV) is involved at an early stage of oncogenesis in many tumors, additional driving events have been postulated to facilitate the progression of SCNECs. Identification of oncogenic drivers could guide targeted therapy of this neoplasm. Clinicopathologic features of 10 cervical SCNECs are reported. Analyses included immunohistochemical evaluation of p16, p53, synaptophysin, and chromogranin expression; in situ hybridizations and polymerase chain reaction for high-risk HPV and/or HPV 18; and next-generation sequencing based on a 637-gene panel. The patients ranged in age from 28 to 68 years (mean, 45.6 y; median, 40.5 y). All tumors had diffuse p16 and synaptophysin expression. All but 1 tumor was positive for chromogranin (extent of staining ranged from focal to diffuse). HPV 18 was detected in 6 tumors and HPV 35 in 1 tumor. At least 1 driver mutation was detected in 8 tumors. Four cases harbored TP53 somatic mutations, 3 of which correlated with an aberrant p53 staining pattern. Four PIK3CA mutations (p.G106A, p.N345T, p.E545K, and p.E545D) were detected in 3 tumors, 2 of which also harbored TP53 mutations. Oncogenic driver mutations involving KRAS, Erbb2, c-Myc, NOTCH1, BCL6, or NCOA3 were detected in 4 tumors. Mutations in caretaker tumor suppressors PTEN, RB1, BRCA1, BRCA2, and ARID1B were also identified in 4 tumors that commonly coharbored activating oncogenic mutations. Targeted next-generation gene sequencing identified genetic alterations involving the MAPK, PI3K/AKT/mTOR, and TP53/BRCA pathways in SCNECs. The presence of genetic alterations that are amenable to targeted therapy in SCNECs offers the potential for individualized management strategies for treatment of this aggressive tumor.

PD-L1, RB1 and mismatch repair protein immunohistochemical expression in neuroendocrine carcinoma, small cell type, of the uterine cervix

AIMS

Neuroendocrine carcinoma, small cell type, of the uterine cervix (SmCC-Cx) is a rare human papilloma virus (HPV) related tumour with limited therapeutic options. Merkel cell carcinoma, another virus-associated neuroendocrine malignancy, has significant programmed death ligand 1 (PD-L1) expression rates. PD-L1 expression has been reported in other malignancies of the cervix. We aimed to determine the prevalence of PD-L1 in the context of mismatch repair protein (MMR) and RB1 expression status in SmCC-Cx.

METHODS AND RESULTS

Ten cases of SmCC-Cx were tested by immunohistochemistry for expression of PD-L1, MLH1, MSH2, MSH6, PMS2, RB1, CD3, CD20 and for HPV by in-situ hybridisation (ISH). PD-L1 expression was scored quantitatively (H-score) in tumour cells and lymphocytes (tumoral/peritumoral). PD-L1 positivity was seen in seven cases, focal in most (H-score range 3-140). Three of nine cases showed MMR deficiency. PD-L1 expression levels correlated with MMR expression status: all three MLH1/PMS2-deficient cases had a ≥5% PD-L1 staining and an H-score ≥10 (P = 0.01). RB1 was lost in four of nine cases, all PD-L1 positive, but this correlation was not statistically significant. Seven of nine tumours were positive for HPV-ISH; two of these had MLH1/PMS2 loss. Of the two HPV-ISH negative tumours, one had MLS1/PMS2 loss.

CONCLUSIONS

PD-L1 expression, predominantly focal, is seen in 70% of SmCC-Cx, while loss of MMR expression is seen in 33% of SmCC-Cx in our cohort. PD-L1 expression in more than 10% of tumour cells is seen in a subset of tumours in association with loss of MMR expression. These patients may be amenable to immune checkpoint inhibitor therapy as a promising alternative for this aggressive disease.

Differential expression of neuroendocrine markers, TTF-1, p53, and Ki-67 in cervical and pulmonary small cell carcinoma

Small cell carcinoma (SCC) is a highly malignant neuroendocrine tumor that may occur in many anatomic sites of the body.In this study, we compared the different expression of neuroendocrine markers, thyroid transcription factor 1 (TTF-1), p53, and Ki-67 in 23 cases of cervical SCC and 56 cases of pulmonary SCC using immunohistochemistry.Our study showed that cervical SCC had a younger onset age than pulmonary counterpart. Although both had the similar morphological features, different immunohistochemical expression panel was observed in this study. As neuroendocrine tumors, SCC of cervix and lung had similar immunoreactive staining for CD56 and chromogranin A, but the expression of the synaptophysin in cervical SCC was significantly higher than that in pulmonary SCC (P = .007). The TTF-1 expression of pulmonary SCC illustrating diffuse and strong positivity in tumor cell nuclei was significantly higher than that of the cervical SCC (P = .003). There was only 1 case showing p53 protein over-expression in the 23 cases of cervical SCC, and p53 over-expression was observed in 42.9% of pulmonary SCC (P = .001). Only 9 cases of cervical SCC showed ≥80% of the Ki-67 proliferation index, while it was found in 94.6% of pulmonary SCC (P < .001).The different immunohistochemical expressions of these 2 kinds of SCCs may be related with their pathogenetic mechanism, and these differences may be helpful in the identification of the origins of the metastatic SCC with unknown primary site.

Cervical small cell carcinoma frequently presented in multiple high risk HPV infection and often associated with other type of epithelial tumors

BACKGROUND

Small cell carcinoma of the uterine cervix is a rare and highly malignant tumor, and its etiopathogenesis is strongly related to high-risk HPV infections.

METHODS

The clinicopathological data of 30 cases of cervical primary small cell carcinoma were retrospectively analyzed. In situ hybridization, polymerase chain reaction and reverse dot-blot hybridization were employed to detect HPV DNA in both small cell carcinoma and other coexisting epithelial tumors. Immunohistochemistry was used to detect the protein expression of p16 and p53.

RESULTS

Amongst 30 patients with cervical primary small cell carcinoma, 15 patients simultaneously exhibited other types of epithelial tumors, including squamous cell carcinoma, adenocarcinoma, squamous cell carcinoma in situ, and adenocarcinoma in situ. Most tumor cells infected with HPV presented integrated patterns in the nuclei by in situ hybridization. HPV DNA was detected in every small cell carcinoma case (100%) by polymerase chain reaction and reverse dot blot hybridization. 27 cases (90%) harbored type 18, and 15 (50%) displayed multiple HPV18 and 16 infections. The prevalence of HPV 18 infection in small cell carcinoma was higher than in cervical squamous and glandular epithelial neoplasms (P = 0.002). However, similar infection rates of HPV 16 were detected in both tumors (P = 0.383). Both small cell carcinoma and other types of epithelial tumors exhibited strong nuclear and cytoplasmic staining for p16 in all cases. Three cases of small cell carcinoma revealed completely negative p53 immunohistochemical expression in 15 cases of composite tumors, which suggested TP53 nonsense mutation pattern. The pure small cell carcinoma of uterine cervix had similar mutation or wild type pattern for TP53 compared with composite tumor (P = 0.224).

CONCLUSIONS

Cervical small cell carcinomas are often associated with squamous or glandular epithelial tumors, which might result from multiple HPV infections, especially HPV 16 infection. Multiple HPV infections were not correlated with tumor stage, size, lymphovascular invasion, lymph node metastasis, or prognosis. Furthermore, careful observation of specimens is very important in finding little proportion of small cell carcinoma in the composite lesions, specifically in cervical biopsy specimens, in order to avoid the missed diagnosis of small cell carcinoma.

Neuroendocrine carcinoma of the cervix: a systematic review of the literature

BACKGROUND

Neuroendocrine carcinoma of the cervix (NECC) is a rare variant of cervical cancer. The prognosis of women with NECC is poor and there is no standardized therapy for this type of malignancy based on controlled trials.

METHODS

We performed a systematic literature search of the databases PubMed and Cochrane Central Register of Controlled Trials to identify clinical trials describing the management and outcome of women with NECC.

RESULTS

Three thousand five hundred thirty-eight cases of NECC in 112 studies were identified. The pooled proportion of NECC among women with cervical cancer was 2303/163470 (1.41%). Small cell NECC, large cell NECC, and other histological subtypes were identified in 80.4, 12.0, and 7.6% of cases, respectively. Early and late stage disease presentation were evenly distributed with 1463 (50.6%) and 1428 (49.4%) cases, respectively. Tumors expressed synaptophysin (424/538 cases; 79%), neuron-specific enolase (196/285 cases; 69%), chromogranin (323/486 cases; 66%), and CD56 (162/267; 61%). The most common primary treatment was radical surgery combined with chemotherapy either as neoadjuvant or adjuvant chemotherapy, described in 42/48 studies. Radiotherapy-based primary treatment schemes in the form of radiotherapy, radiochemotherapy, or radiotherapy with concomitant or followed by chemotherapy were also commonly used (15/48 studies). There is no standard chemotherapy regimen for NECC, but cisplatin/carboplatin and etoposide (EP) was the most commonly used treatment scheme (24/40 studies). Overall, the prognosis of women with NECC was poor with a mean recurrence-free survival of 16 months and a mean overall survival of 40 months. Immune checkpoint inhibitors and targeted agents were reported as being active in three case reports.

CONCLUSION

NECC is a rare variant of cervical cancer with a poor prognosis. Multimodality treatment with radical surgery and neoadjuvant/adjuvant chemotherapy with cisplatin and etoposide with or without radiotherapy is the mainstay of treatment for early stage disease while chemotherapy with cisplatin and etoposide or topotecan, paclitaxel, and bevacizumab is appropriate for women with locally advanced or recurrent NECC. Immune checkpoint inhibitors may be beneficial, but controlled evidence for their efficacy is lacking.

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.

•

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

•

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

•

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

HPV infection and p16INK4A and TP53 expression in rare cancers of the uterine cervix

Cervix cancer remains among most commonly diagnosed cancer in developing countries. Except squamous cell carcinoma and adenocarcinoma, the etiopathology and oncogenic mechanisms of rare cancers remain largely unknown. The study was performed to investigate the value of HPV infection and the expression of p16^INK4A and TP53 in rare primitive cancers of the cervix. We conducted a retrospective study of rare primitive cancers of the cervix. Main clinicopathological features were reported. HPV infection was detected by in situ hybridization. Expression of p16^INK4A and TP53 was analyzed by immunohistochemistry. Overall, seven cases were identified, including basaloid squamous cell carcinoma (BSCC, n = 2), small cell neuroendocrine carcinoma (SCNEC), granulocytic sarcoma without acute myeloid leukemia, leiomyosarcoma, primitive neuroectodermal tumor and botryoid-type embryonic rhabdomyosarcoma. The mean age of patients was 53.7 years. Four cancers were diagnosed at advanced stages. The prognosis was unfavorable and associated with patient death in five cases. HPV types 16/18 were detected in BSCCs and SCNEC. Strong and diffuse p16^INK4A overexpression was described in the nucleus and the cytoplasm of all tumor cells of BSCCs and SCNEC. The remaining cancers exhibited only scattered and focal p16^INK4A staining. Mutated TP53 protein was detected in BSCC (case 1) and GS. Rare cancers of the cervix are aggressive and associated with poor prognosis. In contrast to mesenchymal tumors, BSCCs and SCNEC are etiologically related to high-risk HPV infection and could be identified by block positive p16^INK4A overexpression as common cancers of the cervix. TP53 mutations are not a negligible genetic event in rare cervical cancers.

A systematic review and meta-analysis on the attribution of human papillomavirus (HPV) in neuroendocrine cancers of the cervix

BACKGROUND

There remains uncertainty about the role of human papillomavirus (HPV) infection in causing small-cell neuroendocrine carcinoma (SCNC) and large-cell neuroendocrine carcinoma (LCNC) of the cervix. To clarify the role of HPV in the development of SCNC and LCNC, we conducted a systematic review and meta-analyses.

METHODS

PubMed and Embase were searched to initially identify 143 articles published on or before June 1, 2017. Studies were limited to methods that tested for HPV in the cancer tissue directly to minimize misattribution. Thirty-two studies with 403 SCNC and 9 studies of 45 LCNC were included in the analysis.

RESULTS

For SCNC, 85% (95% confidence interval [95%CI]=71%-94%) were HPV positive, 78% (95%CI=64%-90%) were HPV16 and/or HPV18 positive, 51% (95%CI=39%-64%) were singly HPV18 positive, and 10% (95%CI=4%-19%) were singly HPV16 positive. In a subset of 5 SCNC studies (75 cases), 93% were positive for p16^INK4a by immunohistochemistry and 100% were HPV positive. For LCNC, 88% (95%CI=72%-99%) were HPV positive, 86% (95%CI=70%-98%) were positive for HPV16 or HPV18, 30% were singly HPV18 positive (95%CI=4%-60%), and 29% (95%CI=2%-64%) were singly HPV16 positive.

CONCLUSIONS

In conclusion, most SCNC and LCNC are caused by HPV, primarily HPV18 and HPV16. Therefore, most if not all SCNC and LCNC will be prevented by currently available prophylactic HPV vaccines.

pRb and CyclinD1 Complement p16 as Immunohistochemical Surrogate Markers of HPV Infection in Head and Neck Cancer

Identification of human papillomavirus (HPV) association in head and neck squamous cell carcinoma (HNSCC) is important to identify patients with favorable disease course. However, molecular HPV detection is not universally available. p16 has been proposed as a surrogate marker for HPV infection in HNSCC but, use on its own may result in wrong assignment of some cases to the group of HPV-associated tumors. We have therefore studied 424 HNSCC cases with known p16 and HPV DNA polymerase chain reaction (PCR) status for expression of retinoblastoma protein (pRb) and CyclinD1 by immunohistochemistry using 6-tiered scales (0 to 5) and a combined score (0 to 10). Sixty-one of 424 cases showed overexpression of p16. Of these, 52 cases were HPV DNA-PCR-positive. HPV association strongly correlated with low expression scores for pRb and CyclinD1 individually (scores ≤2) or combined (score sum ≤4), whereas HPV-negative carcinomas showed widely distributed expression scores. High expression scores for pRb or for pRb/CyclinD1 were observed exclusively in HPV DNA-PCR-negative cases. Three of 9 p16-positive/HPV DNA-PCR-negative cases showed high expression of pRb and displayed a high combined pRb/CyclinD1 score. We conclude that HPV-positive HNSCC are characterized by p16 overexpression and low scores for pRb, CyclinD1, and a low combined pRb/CyclinD1 score. High pRb or combined pRb/CyclinD1 scores are strong indicators for HPV-negativity and may justify excluding these cases from further molecular HPV testing. Furthermore p16-positive/HPV DNA-PCR-negative cases show heterogeneous expression of pRb and CyclinD1, including high pRb or high combined pRb/CyclinD1 scores suggesting that at least some of these cases are truly HPV negative.

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.

Human papillomavirus-associated small cell carcinoma/neuroendocrine carcinoma of the oropharynx: a report of two cases

Introduction

Small cell carcinoma/neuroendocrine carcinoma (SCNEC) of the oropharynx is uncommon. Two cases of SCNEC in an 81-year-old woman and in a 54-year-old man are presented here.

Case description

We have documented two cases of SCNEC arising in the oropharynx with evidence of high-risk human papillomavirus (HPV) infection. Histologically, both cases were classified as poorly differentiated SCNEC with high nuclear-to-cytoplasmic ratios and nuclear molding. Observations using a transmission electron microscope revealed membrane-bound neuroendocrine granules in some tumor cells. Both tumors expressed high levels of p16, a surrogate marker for high-risk HPV infection. HPV infection was confirmed in both cases using HPV polymerase chain reaction analysis; HPV subtype 16 was identified in one case and HPV subtype 18 in the other.

Discussion and Evaluation

SCNEC of the oropharynx is a rare and novel HPV-associated disease with neuroendocrine granules and aggressive clinical behavior.

Conclusions

Herein, we present two cases of SCNEC, focusing on its histologic features and treatment modalities. More studies are required to elucidate the pathophysiology of HPV-associated SCNEC in different organ systems.

Electronic supplementary material

The online version of this article (doi:10.1186/s40064-016-3501-x) contains supplementary material, which is available to authorized users.

Evaluation of p16INK4a immunostaining for the detection of high-grade changes in cervical cytology

Since its introduction in Australia in 2007, the human papillomavirus (HPV) vaccine has led to a markedly lower prevalence of vaccine targeted HPV genotype infections as well as HPV disease including genital warts and histologically confirmed high-grade (HG) cervical abnormalities. To increase the ability to identify abnormal cells in lower prevalence, adjunct markers can be incorporated to improve the sensitivity and specificity of cytology test. One such marker is p16(p16), which is detectable in cells expressing the E7 oncogene encoded by high-risk HPVs (HR-HPV). In this study, the sensitivity and specificity of p16 immunostaining in detection of underlying HG lesions was evaluated in a cohort of 454 women undergoing surgical treatment for biopsy proven cervical dysplasia. Overall, p16 positive cells were detected in 321 (71%) of cytology preparations evaluated. Comparison of p16 staining on cytological preparations to histology diagnosis available on 212 patients, showed 26 (54%), 41 (78%) and 80 (90%) of cytology preparations to be p16 positive in women with CIN1, CIN2 and CIN3, respectively (p < 0.005). HPV16 and 18 were the most prevalent genotypes in HG lesions and were highly correlated with p16 staining. p16 staining provides an additional marker which can assist in better detecting underlying HG lesion in cytology smears with low disease prevalence.

Sequencing of mutational hotspots in cancer-related genes in small cell neuroendocrine cervical cancer

OBJECTIVES

Small cell cervical cancer is a rare malignancy with limited treatment options for recurrent disease. We sought to determine if tumor specimens of small cell cervical cancer harbor common somatic mutations and if any of these are actionable.

METHODS

Using a registry of patients with neuroendocrine cervical cancer, we identified 44 patients with pure or mixed small cell cervical cancer who had undergone mutational analysis. Mutations had been detected using next generation sequencing of mutational hotspots in 50 cancer-related genes.

RESULTS

Thirty-five mutations were identified in 24 patients (55%). Fifteen of these 24 patients (63%) had 1 mutation, 7 patients (29%) had 2 mutations, and 2 patients (8%) had 3 mutations. In all 44 patients, the most commonly seen mutations were mutations in PIK3CA (8 patients; 18%), KRAS (6 patients; 14%), and TP53 (5 patients; 11%). No other mutation was found in >7% of specimens. Of the 24 patients who had a mutation, 21 (88%) had at least 1 alteration for which there currently exists a class of biological agents targeting that mutation. In the entire cohort of 44 patients, 48% had at least 1 actionable mutation.

CONCLUSION

Although no single mutation was found in the majority of patients with small cell cervical cancer, almost half had at least 1 actionable mutation. As treatment options for patients with recurrent small cell cervical cancer are currently very limited, molecular testing for targetable mutations, which may suggest potential therapeutic strategies, may be useful for clinicians and patients.

Neuroendocrine tumours in rare sites: differences in nomenclature and diagnostics-a rare and ubiquitous histotype

The diagnosis of neuroendocrine tumours in typical sites, as gastrointestinal tract and lung, is based upon well-coded criteria that have become familiar to most of the pathologists. Much more difficult is the recognition and allocation of proper nomenclature to be referred to the same histotype in locations where these tumours have a lower incidence. The aim of our review was to provide a quick handbook of the main diagnostic pitfalls known in literature that can interpose in the histopathological examination of neuroendocrine tumours in rare sites (urinary system and male genital organs, female genital organs, head and neck and breast).

Small cell carcinoma of the anus in the setting of prior squamous dysplasia and carcinoma in situ

Small cell carcinoma of the anus is a rare tumor that has been infrequently described in the literature. In contrast to squamous cell carcinoma, which is known to be associated with high-risk subtypes of human papillomavirus (HPV), the etiology of small cell carcinoma of the anal canal is not established. We present a case of a patient with small cell carcinoma of the anal canal in the setting of prior squamous dysplasia and carcinoma in situ. In conjunction with recently published data demonstrating the presence of HPV in tumor specimens from patients with small cell carcinoma of the anal canal, our patient's clinical course suggests a possible link between HPV and this rare malignancy.

Potential impact of a nine-valent vaccine in human papillomavirus related cervical disease

Background

Information on human papillomavirus (HPV) type distribution is necessary to evaluate the potential impact of current and future HPV vaccines. We estimated the relative contribution (RC) to invasive cervical cancer (ICC) and precancerous cervical lesions of the nine HPV types (HPV 6/11/16/18/31/33/45/52/58) included in an HPV vaccine currently under development.

Methods

Estimations on ICC were based on an international study of 8,977 HPV positive cases and estimations on precancerous cervical lesions were extracted from a published meta-analysis including 115,789 HPV positive women. Globocan 2008 and 2010 World Population Prospects were used to estimate current and future projections of new ICC cases.

Results

RC of the 9 HPV types in ICC was 89.4%, with 18.5% of cases positive for HPV 31/33/45/52/58. Regional variations were observed. RCs varied by histology, ranging between 89.1% in squamous cell carcinomas (SCC) and 95.5% in adenocarcinomas (ADC). HPV 16/18/45 were detected in 94.2% of ADC. RC of the 9 types altogether decreased with age (trend test p < 0.0001), driven by the decrease in older ages of HPV 16/18/45. In contrast, the RC of HPV 31/33/52/58 increased with age. Due to population growth alone, projected estimates of ICC cases attributable to the 9 types are expected to rise from 493,770 new cases in 2012 to 560,887 new cases in 2025.

The RCs of individual high risk HPV types varied by cytological and histological grades of HPV-positive precancerous cervical lesions, and there was an under representation of HPV 18 and 45 compared to ICC.

Conclusions

The addition of HPV 31/33/45/52/58 to HPV types included in current vaccines could prevent almost 90% of ICC cases worldwide. If the nine-valent vaccine achieves the same degree of efficacy than previous vaccines, world incidence rates could be substantially reduced.

A clinical review of small-cell carcinoma of the urinary bladder

Small-cell carcinoma of the urinary bladder is a rare and aggressive type of bladder cancer that has a poor prognosis. The incidence has been gradually increasing because of the aging population. Owing to its rarity there are no available treatment guidelines. Several retrospective studies and 1 prospective study have provided some insight into therapy for this disease. A multimodal approach that includes chemotherapy, local radiation therapy, and definitive surgery in resectable cases appears to be an optimal management approach.

Human papillomavirus-related small cell carcinoma of the oropharynx

Human papillomavirus (HPV)-related oropharyngeal squamous cell carcinoma (OPSqCC) represents an important subgroup of head and neck cancer that is characterized by a distinct risk factor profile, a relatively consistent microscopic appearance, and a favorable prognosis. A growing experience with HPV testing of OPSqCCs has uncovered variants that deviate from prototypic HPV-related cancer with respect to morphology but not clinical behavior. In effect, HPV positivity confers a favorable prognosis independent of morphologic subtype. We report 5 cases of HPV-related oropharyngeal carcinomas with well-developed features of small cell carcinoma (SCC) to define the prognostic impact of HPV positivity in a tumor type universally regarded as highly aggressive. Four of the SCCs arose in association with a conventional HPV-related OPSqCC. All 5 SCCs were HPV positive by in situ hybridization. By immunohistochemistry, all 5 cases were p16 positive, synaptophysin positive, and cytokeratin 5/6 negative. Four of the patients were men. The mean age was 61 years (range, 49 to 67 y). The SCCs were associated with metastatic spread to distant sites (60%) and poor survival outcomes: 3 patients (60%) died as a result of their disease (mean survival time, 10 mo; range, 6 to 15 mo). HPV testing has disclosed a previously unrecognized variant of HPV-related oropharyngeal carcinoma that is microscopically characterized by the small cell phenotype. Recognition of this component, even in association with conventional HPV-related OPSqCC, is important as it may indicate an aggressive phenotype that supersedes HPV positivity as a prognostic indicator.

Primary squamous cell carcinoma of the vagina: human papillomavirus detection, p16(INK4A) overexpression and clinicopathological correlations

AIM

To determine the role of human papillomavirus (HPV) in the pathogenesis of primary squamous cell carcinoma of the vagina (SCCVa), and to evaluate its clinicopathological significance.

METHODS AND RESULTS

All cases of SCCVa diagnosed over a 15-year period from two hospitals in Barcelona, Spain (n=32) were retrieved. Patients with a history of carcinoma of the cervix diagnosed <5 years before were excluded. HPV was detected and typed by polymerase chain reaction (PCR) using SPF10 primers. Immunohistochemistry was performed for p16 and p53. HPV was detected in 25 cases (78.1%). HPV16 was the most prevalent type. Patients with HPV-positive tumours were associated frequently with a history of carcinoma or intraepithelial neoplasia of the cervix or vulva diagnosed more than 5 years before (56% versus 0%; P=0.01). HPV-positive tumours were more frequently of non-keratinizing, basaloid or warty type than HPV-negative neoplasms (84% versus 14.3%; P<0.001), and showed diffuse positive immunoreactivity for p16(INK4a) (96%, versus 14.3%; P<0.001). The sensitivity and specificity of p16 to identify HPV-positive tumours were 96% and 85.7%, respectively.

CONCLUSIONS

A high number of SCCVs are related to HPV infection and may be identified by immunohistochemistry for p16. HPV-positive tumours tend to affect women with history of cervical neoplasia.

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.

Inverse p16 and p63 expression in small cell carcinoma and high-grade urothelial cell carcinoma of the urinary bladder

Small cell carcinoma (SmCC) of the urinary bladder is a rare, highly aggressive neoplasm. The diagnosis is usually made on morphologic grounds, with the help of immunohistochemistry to document neuroendocrine differentiation. However, neuroendocrine markers generally have low sensitivity, ranging between 30-70%. Recent studies have reported p16 over-expression in SmCC of the lung, suggesting that p16 immunohistochemistry may be useful in the diagnosis of bladder SmCC. This is the first study to analyze the usefulness of p16 in the distinction of small cell and high grade urothelial cell carcinoma (HG-UCC). Fourteen cases of SmCCs and sixteen cases of HG-UCC of the bladder were stained with p16, p63, cytokeratin 20 (CK20), cytokeratin 7 (CK7), chromogranin (Chr), synaptophysin (Syn), and CD56. P16 expression was significantly higher in SmCCs (92.8%) when compared to HG-UCCs (43.7%). P63 and CK20, on the other hand, were positive in the majority of HG-UCCs (81.3% and 50%, respectively), while only 14.3% of SmCCs showed focal immunoreactivity with CK20. The sensitivity of the traditional neuroendocrine markers was low, ranging between 28.6% (Chr) and 71.4% (CD56) in SmCCs. P16 positivity in the absence of p63 and CK20 is highly characteristic of SmCC, while p63 and CK20 positivity with or without p16 expression is typical of HG-UCC.

Usefulness of p16 for differentiating primary pulmonary squamous cell carcinoma from cervical squamous cell carcinoma metastatic to the lung

To date, there is no reliable immunohistochemical marker that discriminates between primary pulmonary squamous cell carcinoma (SCC) and cervical SCC metastatic to the lung. In this study, immunohistochemical staining of p16 was performed on 33 primary pulmonary SCCs, 48 primary cervical SCCs, and 17 cases of cervical SCC with pulmonary metastasis. Expression of p16 was noted in 47 cases of cervical SCC (47/48 [98%]), and all were strongly stained. Of the 7 cases of primary pulmonary SCC (7/33 [21%]) in which p16 expression was detected, 3 were weakly positive, 1 was moderately positive, and 3 were strongly positive. Among these p16+ pulmonary SCCs, only 1 showed detectable human papillomavirus DNA. Of the 17 cases of cervical SCC with pulmonary metastasis, all of the pulmonary and cervical tumors were positive for p16. p16 is a useful marker for the discrimination between cervical and pulmonary SCCs. The performance of p16 staining at different cutoff values was also compared.

Squamous intraepithelial lesions arising in benign endocervical polyps: a report of 9 cases with correlation to the Pap smears, HPV analysis, and immunoprofile

Endocervical polyps are common benign lesions that typically arise in the endocervical canal of women from 40 to 60 years old. The reported incidence of squamous intraepithelial lesion (SIL) occurring in an endocervical polyp is typically less than 1/1,000 (0.1%). We report on 9 cases of SIL arising in otherwise classic benign endocervical polyps; these lesions were from a pool of about 1500 endocervical polyps for an incidence of approximately 0.5%. Five cases were low-grade SIL; of the 4 cases of high-grade SIL, 1 was associated with an invasive squamous cell carcinoma. In 8/9 cases, there was no evidence of SIL on colposcopic examination or biopsy of the remainder of the cervix. There were 12 Pap smears (either concurrent or from 6 mo to 2 yr before the biopsy-proven SIL) taken from the 9 women and most (10/12%-83%) were diagnosed as normal (7), atypical squamous cells of undetermined significance (ASCUS), favor reactive changes (1), or ASCUS (2) whereas the other 2 (17%) smears were diagnosed as low-grade SIL. Human papillomavirus DNA was evident in 7/8 (88%) of the polyps with SIL as determined by in situ hybridization. We conclude that cervical SILs can occur de novo in endocervical polyps, their incidence may be increasing, and, due to their presence in the endocervical canal, where they are much less accessible to sampling with a cytobrush/spatula, may not be evident in the Pap smear.

Diagnostic utility of p16INK4a: a reappraisal of its use in cervical biopsies

p16(INK4a), an indirect marker of cell cycle dysregulation, is commonly expressed in cervical dysplasias and carcinomas associated with high risk human papillomavirus (HR-HPV) infections. Although p16(INK4a) immunohistology is routinely used as a cost effective surrogate marker, many of the published articles are confusing and contradictory. The discrepancies can be ascribed to a multitude of factors operating at the molecular, technical and interpretative levels. In the first place, our simplistic model of viral mediated oncogenesis is speculative and fails to account for all the known biomolecular changes. Unresolved technical issues include the variables of tissue fixation, antibody dilution, antibody isotype and clone, and the sensitivity of the particular detection method. Within any controlled staining method, strong diffuse or 'block' immunoreactivity in squamous cells may be found in moderate/severe dysplasia (CIN 2/3) and invasive squamous carcinoma. In contrast, focal or multifocal reactivity in squamous cells may be artefactual, related to low risk or HR-HPV. p16(INK4a) is less reliable when dealing with glandular lesions since considerable overlap exists between reactive and dysplastic lesions. In addition not all glandular dysplasias/carcinomas are HR-HPV related, nor are all p16(INK4a) immunoreactive lesions associated with HR-HPV. We conclude that p16(INK4a) immunoperoxidase shows greater specificity than sensitivity for squamous lesions; in comparison, glandular dysplasias/carcinomas show reduced specificity and sensitivity. Like all cell cycle regulatory proteins, the future diagnostic role of p16(INK4a) is limited. The ideal diagnostic molecular test for cervical dysplasias will detect a HR-HPV related product after, but not before, cell transformation and will reliably predict those cases yet to experience disease progression.

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.

Expression of p21Cip1/Waf1 and p27Kip1 in Small Cell Neuroendocrine Carcinoma of the Uterine Cervix

Small-cell neuroendocrine carcinoma of the uterine cervix (SCCC), a rare but malignant cervical neoplasm, has a highly aggressive phenotype that requires more intensive treatment than other cervical tumors. Immunohistochemical methods were used to compare the expression of p21Cip1/Waf1 and p27Kip1 in SCCC and squamous cell carcinoma, the most common type of cervical cancer. In SCCC, p21 expression was significantly reduced compared with squamous cell carcinoma, whereas expression of p27 was similar in both carcinomas. Reduced expression of p21 could be a helpful diagnostic marker and may contribute to the invasive phenotype of SCCC.

Detection of human papillomavirus and relevant tumor suppressors and oncoproteins in laryngeal tumors

PURPOSE

The mechanism of larynx oncogenesis is complex and controlled by various factors, most of them involved in cell proliferation and apoptosis. In this study, we evaluated the levels of two suppressor proteins (pRb and p53) and two oncogenic proteins (c-Myc and Bcl-2), as well as the apoptotic levels and the presence of human papillomavirus (HPV) in both tumor types.

EXPERIMENTAL DESIGN

Low- or high-risk HPV viral DNA was determined by PCR and in situ PCR; the level of cellular proteins was examined by immunohistochemistry; the presence of apoptotic cells was evaluated by in situ cell death detection.

RESULTS

Most laryngeal papillomatosis samples contained low-risk HPV determined by both techniques. However, 25% of laryngeal carcinoma samples were positive for HPV employing PCR or in situ PCR. In papillomatosis, pRb and p53 levels were higher than in normal larynxes, whereas laryngeal cancer presented the lowest levels. c-Myc oncogene expression was very low in normal and cancer tissues but highly increased in papillomatosis. Bcl-2 expression was low and showed no significant difference between laryngeal papillomatosis and normal larynxes. By contrast, Bcl-2 was clearly up-regulated in cancer. Normal larynx samples and those from laryngeal papillomatosis exhibited similar relatively high numbers of apoptotic cells, whereas in malignant tumors, these cells were scarce.

CONCLUSION

Our results suggest that HPV is an important risk factor in papillomatosis and in some malignant larynx tumors with a strong participation of cellular genes, specifically involved in proliferation and apoptosis. In benign papillomatosis lesions but not in larynx cancer, high p53 activity might preserve the apoptosis process. In larynx cancer, low p53 levels and high bcl-2 expression may be playing an important role to block apoptosis.

Biomarker-assisted diagnosis of ovarian, cervical and pulmonary small cell carcinomas: the role of TTF-1, WT-1 and HPV analysis

AIMS

Small cell carcinoma of the ovary, hypercalcaemic-type (SCCOH) is morphologically similar to small cell carcinomas from other sites. The aims of this study were to (i) determine if a biomarker panel would distinguish small cell carcinomas of the ovary, cervix (SCCCx) and lung (SCCLu) and (ii) potentially determine the histogenesis of SCCOH.

METHODS AND RESULTS

Nine ovarian small cell carcinomas (seven hypercalcaemic type; two pulmonary type), eight SCCCx and 22 SCCLu were immunostained for thyroid transcription factor (TTF)-1, WT-1, p16, cKIT and OCT3/4; a subset of cases were tested for human papillomavirus (HPV). WT-1 was diffusely positive in 6/7 SSCOH versus two of 33 other small cell carcinomas (P <or= 0.001). TTF-1 was diffusely positive in 20/22 SCCLu and 1/8 SCCCx, and negative in all SCCOH. p16 and cKIT demonstrated variable patterns of immunoreactivity in all cases. HPV was identified in 5/6 SCCCx; SCCOH and SCCLu were negative for HPV.

CONCLUSIONS

Combined staining with WT-1 and TTF-1 will distinguish SCCOH from SCCLu and SCCCx with a sensitivity of 86% and specificity of 97%. HPV is specific for tumours of cervical origin, but p16 immunohistochemistry is not useful for this purpose. The presence of diffuse WT-1 supports a Müllerian origin for SCCOH, whereas the absence of cKIT and OCT3/4 argues against a germ cell origin.

Extrapulmonary small cell carcinomas express K homology domain containing protein overexpressed in cancer, but carcinoid tumors do not

A number of malignancies, including high-grade neuroendocrine carcinomas of the lung, have been reported to express K homology domain containing protein overexpressed in cancer (KOC), a member of the insulin-like growth factor messenger RNA-binding protein (IMP) family also known as L523S and IMP3. KOC acts to promote tumor cell proliferation by enhancing insulin-like growth factor-II protein expression. This study aimed to examine KOC expression pattern in extrapulmonary neuroendocrine tumors. Seventy-five extrapulmonary neuroendocrine tumors that were surgically resected or had undergone biopsy, including 53 small cell carcinomas (uterine cervix, 21; bladder, 10; colorectum, 13; prostate, 7; stomach, 1; and esophagus, 1) and 22 carcinoid tumors (colorectum, 10; appendix, 5; ileum, 4; duodenum, 2; and stomach, 1), were immunohistochemically studied using a monoclonal antibody against KOC. Our results demonstrated that 47 small cell carcinomas (89%) showed moderate to strong positive staining for KOC, with 25 cases (53%) showing positivity in more than 90% of tumor cells and 22 cases (47%) in 40% to 80% of tumor cells. Three cases showed weak staining in 5% to 10% of the tumor cells. The remaining 3 cases (uterine cervix, 2; bladder, 1) showed completely negative immunoreactivity. No KOC immunostaining was detected in 22 carcinoid tumors. These findings indicate that KOC may play an important role in the regulation of biologic behavior of extrapulmonary small cell carcinomas. In addition, immunohistochemical detection of KOC expression may serve as a useful diagnostic tool in the distinction between small cell carcinoma and carcinoid tumor, particularly when the diagnostic material is a small biopsy with crushing artifact.

Small cell carcinoma of the urinary bladder--histogenesis, genetics, diagnosis, biomarkers, treatment, and prognosis

Small cell carcinoma of the urinary bladder is a rare but highly aggressive malignancy with a dismal prognosis. Most patients present with advanced disease at the time of diagnosis. Hematuria is the most frequent presenting symptom. Histologically, small cell carcinoma of the urinary bladder is indistinguishable from its pulmonary counterpart. Coexistence with other types of carcinoma is common. Histogenesis is uncertain; there are several competing theories, including origin from stem cells, from urothelial cells, and from neuroendocrine cells in normal or metaplastic urothelium. The molecular pathogenesis remains unclear. Immunohistochemical staining can be extremely helpful in establishing the diagnosis, and in investigating the use of potential therapeutic strategies. Currently, combinations of surgical resection, chemotherapy, and radiation therapy represent the main treatment options. The recent observation of c-kit and epidermal growth factor receptor expression in more than 25% of patients with urinary bladder small cell carcinoma opens new avenues for further investigation. Improvement in survival may depend upon the identification of new molecular markers to facilitate earlier diagnosis and the development of novel targeted therapies. In this paper, we review general aspects of small cell carcinoma of the urinary bladder, focusing on the ways in which our understanding of this entity has been positively influenced by studies of the histopathologic and immunohistochemical findings, and by investigations of genetic alterations in this disease.

The pathology of extrapulmonary small cell carcinoma

Extrapulmonary small cell carcinomas (EPSCCs) are uncommon malignant neoplasms with a reported incidence of 0.1% to 0.4% in the United States. Since their first description in 1930, they have been seen in nearly every organ system. Like their more common pulmonary counterparts, EPSCCs are thought to arise from a multipotential stem cell. However, there is recent molecular evidence that small cell elements may arise as a late-stage phenomenon in the genetic progression of more organ-typical carcinomas. The morphologic, immunohistochemical, and ultrastructural features are similar to those described in pulmonary small cell carcinomas (PSCCs). The differential diagnosis of EPSCC includes PSCC, other neuroendocrine tumors, small round blue cell tumors, metastatic melanoma, lymphoma, and poorly differentiated non-small cell carcinomas. Molecular alterations reported to occur in EPSCCs include abnormalities described in PSCC and changes found in carcinomas more typically encountered in the organ from which they arise. In this article we discuss the pathology of EPSCC with a review of theories of histogenesis, sites of occurrence, diagnostic features, differential diagnosis, molecular alterations, and clinical behavior.

Small-cell carcinoma of the urinary bladder: diagnosis and management

Small-cell carcinoma of the urinary bladder (SCCUB) accounts for less than 1% of all cancers arising in the urinary bladder. Current diagnosis and management of SCCUB are often patterned after small-cell lung cancer (SCLC). However, SCCUB therapy is different from that for SCLC. For example, many patients with SCCUB undergo local resection, which is rarely performed in SCLC. As in SCLC, platinum-etoposide combination chemotherapy is employed as the main systemic treatment option for SCCUB. Chemotherapy is usually combined with other therapeutic modalities, especially in patients whose disease is limited to the locoregional area. Owing to the rarity of this malignancy, no prospective study has been performed that establishes the efficacy and duration of chemotherapy or the relative efficacy of platinum-etoposide versus other chemotherapeutic regimens. This article provides a comprehensive review of the current status of SCCUB diagnosis and management, as well as some unique insights into this rare tumor.

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.