Immunohistochemical expression of somatostatin type 2A receptor in neuroendocrine carcinoma of uterine cervix

Neuroendocrine Neoplasms of the Gastrointestinal Tract versus Neuroendocrine Neoplasms of the Gynaecological Tract-Comparison of the Risk Factors and Non-Surgical Treatment Efficacy

Neuroendocrine tumours of the gastrointestinal tract are rare. The incidence has increased in recent years due to improvements in diagnostic methods for detecting these lesions. These tumours have a poor prognosis, especially when detected at an advanced stage. The basis of the treatment is resection, and non-surgical treatments are also standard in the treatment process. The situation is similar in even rarer neuroendocrine tumours of the reproductive tract, which are associated with an equally poor prognosis. In this article, we focus on learning about the risk factors (including genetic mutations) that increase the risk of the disease and comparing the effectiveness of non-surgical treatments-chemotherapy, radiotherapy, peptide receptor radionuclide therapy, somatostatin analogues, and immunotherapy. The efficacy of these treatments varies, and immunotherapy appears to be a promising form of treatment; however, this requires further research.

Large-cell neuroendocrine carcinoma of the gynecologic tract: Prevalence, survival outcomes, and associated factors

BACKGROUND

We aimed to assess the clinical behavior of gynecologic large-cell neuroendocrine carcinoma (LCNEC) via a retrospective analysis of data from 469 patients.

METHODS

Patients diagnosed with gynecologic LCNEC from 1988 to 2015 were identified using the Surveillance, Epidemiology, and End Results database. Univariate and multivariate Cox hazard regression analyses were performed to assess independent predictors of overall survival (OS) and cancer-specific survival (CSS). OS and CSS were also evaluated using the Kaplan-Meier method, and the effects of different treatment regimens on prognosis were compared according to disease stage.

RESULTS

Cervical, ovarian, and endometrial LCNEC were observed in 169, 219, and 79 patients, respectively. The 5-year OS rates for patients with cervical, ovarian, and endometrial LCNEC were 35.98%, 17.84%, and 23.21%, respectively, and the median duration of overall survival was 26, 11, and 11 months in each group. The 5-year CSS rates for the three groups were 45.23%, 19.23%, and 31.39%, respectively, and the median duration of CSS was 41, 12, and 11 months in each group. Multivariate analysis revealed that American Joint Committee on Cancer stage, lymph node metastasis, and chemotherapy were independent prognostic factors for OS and CSS in patients with cervical LCNEC. Lymph node metastasis, surgery, and chemotherapy were independent prognostic factors for OS and CSS in the ovarian group and for OS in the endometrial group. Lymph node metastasis and surgery were also independent prognostic factors for CSS in the endometrial group.

CONCLUSION

Surgery alone may help to improve overall survival and CSS in patients with early-stage cervical LCNEC. In contrast, surgery+chemotherapy and surgery+radiotherapy may help to improve survival in those with early-stage ovarian and endometrial LCNEC, respectively. Regardless of subtype, comprehensive treatment involving surgery, CTX, and RT should be considered to improve prognosis in patients with advanced-stage gynecologic LCNEC.

Emerging Therapeutic Concepts and Latest Diagnostic Advancements Regarding Neuroendocrine Tumors of the Gynecologic Tract

Neuroendocrine neoplasms (NENs) are particularly rare in all sites of the gynecological tract and include a variety of neoplasms with variable prognosis, dependent on histologic subtype and site of origin. Following the expert consensus proposal of the International Agency for Research on Cancer (IARC), the approach in the latest World Health Organization (WHO) Classification System of the Female Genital Tumours is to use the same terminology for NENs at all body sites. The main concept of this novel classification framework is to align it to all other body sites and make a clear distinction between well-differentiated neuroendocrine tumors (NETs) and poorly differentiated neuroendocrine carcinomas (NECs). The previous WHO Classification System of the Female Genital Tumours featured more or less the same principle, but used the terms ‘low-grade neuroendocrine tumor’ and ‘high-grade neuroendocrine carcinoma’. Regardless of the terminology used, each of these two main categories include two distinct morphological subtypes: NETs are represented by typical and atypical carcinoid and NEC are represented by small cell neuroendocrine carcinoma (SCNEC) and large cell neuroendocrine carcinoma (LCNEC). High-grade NECs, especially small cell neuroendocrine carcinoma tends to be more frequent in the uterine cervix, followed by the endometrium, while low-grade NETs usually occur in the ovary. NENs of the vulva, vagina and fallopian tube are exceptionally rare, with scattered case reports in the scientific literature.

The puzzle of gynecologic neuroendocrine carcinomas: State of the art and future directions

Primary gynecologic neuroendocrine carcinomas (gNECs) are a heterogeneous spectrum of rare and highly aggressive neoplasms, accounting for about 2% of all gynecologic malignancies, which mostly resemble the small cell lung carcinoma (SCLC). Due to the lack of standardized treatment guidelines, their management poses a noteworthy clinical challenge. Currently, cumulative data retrieved from the management of SCLC and from retrospective studies supports a multimodality strategy, based on surgery, chemotherapy, and radiotherapy. Nevertheless, the prognosis remains poor and recurrences are extremely frequent. Hence, there is an urgent need for novel treatment options and promising molecular targets. Recently, there has been an increasing interest on the potential role of immune checkpoint inhibitors, especially in the recurrent setting. However, only scant evidence exists and there is still a long road ahead. A solid collaboration between gynecologists and oncologists worldwide is required to improve the treatment of these puzzling tumors.

Gynecologic large cell neuroendocrine carcinoma: A review

Large cell neuroendocrine carcinomas (LCNEC) are rare, aggressive high-grade neuroendocrine neoplasms within the neuroendocrine cell lineage spectrum. This manuscript provides a detailed review of published literature on LCNEC of gynecological origin. We performed a PubMed search for material available on gynecologic LCNEC. We analyzed 104 unique cases of gynecologic LCNECs, of which 45 were cervical primary, 45 were ovarian, 13 were uterine, and 1 was vaginal. A total of 45 cases of cervical LCNEC were identified with a median age of 36 years. Median overall survival was 16 months. We identified 45 ovarian LCNEC cases in the published literature with a median age of 54 years. Median overall survival was 8 months. 13 LCNEC cases of uterine origin were identified; 12 out of 13 were of endometrial origin and the median age was 71 years. The majority of patients presented with Stage III/IV disease (stages I-IV were 31%, 8%, 38%, and 23%, respectively). Gynecologic LCNEC is an aggressive malignancy. Our current understanding of the disease biology is very limited. Efforts are required to better understand the genomic and molecular characterizations of gynecological LCNEC. These efforts will elucidate the underlying oncogenic pathways and driver mutations as potential targets.

Diagnostic value of four neuroendocrine markers in small cell neuroendocrine carcinomas of the cervix: a meta-analysis

Small cell neuroendocrine carcinoma of the cervix (SCNECC) is a highly invasive cervical cancer. The immunohistochemical criteria is an important aspect for assistant diagnosis of SCNECC. However, which markers can be appropriate selection for diagnosing SCNECC were not determined. The aim was to systematically evaluate expression levels of four neuroendocrine markers (containing synaptophysin (Syn), neural cell adhesion molecules (CD56), neuron-specific enolase (NSE) and chromograninA (CgA)) and to find out the appropriate selection for diagnosing SCNECC. Four English and three Chinese libraries were retrieved between 1984 and 2020. 23 studies about NSE, 36 studies about Syn, 23 studies about CD56 and 36 studies about CgA (all studies containing 581 patients) were eligible for meta-analyses. The pooled positive expression percentages (95% CI; I²) were as follows: 84.84% (79.41–90.27%; 76.7%) for Syn, 84.53% (79.43–89.96%; 37.5%) for CD56, 77.94% (69.13–86.76%; 83.5%) for NSE, and 72.90% (67.40–78.86%; 59.7%) for CgA. The positive proportions (95% CI; I²) ranked top three of simultaneous expressions of two markers were 87.75% (82.03–93.87%, 33.3%) for Syn and CD56, 70.92% (50.50–87.68%, 82.7%) for Syn and NSE, 65.65% (53.33–76.98%, 73.5%) for Syn and CgA. This confirms that Syn and CD56 are reliable indicators for diagnosing SCNECC.

Evaluation of PARP and PDL-1 as potential therapeutic targets for women with high-grade neuroendocrine carcinomas of the cervix

OBJECTIVES

Women with recurrent high-grade neuroendocrine cervical cancer have few effective treatment options. The aim of this study was to identify potential therapeutic targets for women with this disease.

METHODS

Specimens from patients with high-grade neuroendocrine carcinomas of the cervix were identified from pathology files at MD Anderson Cancer Center. Immunohistochemical stains for PD-L1 (DAKO, clone 22-C3), mismatch repair proteins (MLH1, MSH2, MSH6, PMS2), somatostatin, and Poly (ADP-ribose) polymerase (PARP) were performed on sections from formalin-fixed paraffin-embedded tissue blocks. Nuclear PARP-1 staining was quantified using the H-score with a score of <40 considered low, 40-100 moderate, and ≥100 high.

RESULTS

Forty pathologic specimens from patients with high-grade neuroendocrine carcinomas of the cervix were examined (23 small cell, 5 large cell, 3 high-grade neuroendocrine, not otherwise specified, and 9 mixed). The mean age of the cohort was 43 years and the majority of patients (70%) were identified as white non-Hispanic. All 28 (100%) samples tested stained for mismatch repair proteins demonstrated intact expression, suggesting they were microsatellite stable tumors. Of the 31 samples tested for PD-L1 expression, only two (8%) of the 25 pure high-grade neuroendocrine carcinomas were positive whereas three (50%) of the six mixed carcinoma tumors tested positive. Of the 11 small cell specimens tested for PARP-1, 10 (91%) showed PARP expression with six (55%) demonstrating high expression and four (36%) showing moderate expression. Somatostatin staining was negative in 18 of 19 small cell cases (95%).

CONCLUSIONS

Pure high-grade neuroendocrine cervical carcinomas were microsatellite stable and overwhelmingly negative for PD-L1 expression. As the majority of tumors tested expressed PARP-1, inclusion of PARP inhibitors in future clinical trials may be considered.

Neuroendocrine Carcinoma of the Uterine Cervix: A Clinicopathologic and Immunohistochemical Study with Focus on Novel Markers (Sst2-Sst5)

BACKGROUND

Gynecological neuroendocrine neoplasms (NENs) are extremely rare, accounting for 1.2-2.4% of the NENs. The aim of this study was to test cervical NENs for novel markers of potential utility for differential diagnosis and target therapy.

METHODS

All cases of our center (n = 16) were retrieved and tested by immunohistochemistry (IHC) for 12 markers including markers of neuroendocrine differentiation (chromogranin A, synaptophysin, CD56), transcription factors (CDX2 and TTF1), proteins p40, p63, p16INK4a, and p53, somatostatin receptors subtypes (SST2-SST5) and the proliferation marker Ki67 (MIB1).

RESULTS

All cases were poorly differentiated neuroendocrine carcinomas (NECs), 10 small cell types (small cell-neuroendocrine carcinomas, SCNECs) and 6 large cell types (large cell-neuroendocrine carcinomas, LCNECs); in 3 cases a predominant associated adenocarcinoma component was observed. Neuroendocrine cancer cells expressed at least 2 of the 3 tested neuroendocrine markers; p16 was intensely expressed in 14 (87.5%) cases; SST5 in 11 (56.25%, score 2-3, in 9 cases); SST2 in 8 (50%, score 2-3 in 8), CDX2 in 8 (50%), TTF1 in 5 (31.25%), and p53 in 1 case (0.06%). P63 and p40 expressions were negative, with the exception of one case that showed moderate expression for p63.

CONCLUSIONS

P40 is a more useful marker for the differential diagnosis compared to squamous cell carcinoma. Neither CDX2 nor TTF1 expression may help the differential diagnosis versus potential cervical metastasis. P16 expression may suggest a cervical origin of NEC; however, it must be always integrated by clinical and instrumental data. The expression of SST2 and SST5 could support a role for SSAs (Somatostatin Analogues) in the diagnosis and therapy of patients with cervical NECs.

Insulinoma-associated protein 1 (INSM1): a potential biomarker and therapeutic target for neuroendocrine tumors

BACKGROUND

Insulinoma-associated protein 1 (INSM1), a transcriptional regulator with a zinc-finger DNA-binding domain, has been validated as a cytoplasmic marker for neuroendocrine differentiation of tumor cells. Next to its abundant expression in the fetal pancreas, it is expressed in brain tumors, pheochromocytomas, medullary thyroid carcinomas, insulinomas and pituitary and small-cell lung carcinomas. INSM1 is not expressed in normal adult tissues and/or most non-neuroendocrine tumors. It regulates various downstream signaling pathways, including the Sonic Hedgehog, PI3K/AKT, MEK/ERK1/2, ADK, p53, Wnt, histone acetylation, LSD1, cyclin D1, Ascl1 and N-Myc pathways. Although INSM1 appears to be a subtle and specific biomarker for neuroendocrine tumors, its role in tumor development has remained unclear.

CONCLUSIONS

Here, we highlight INSMI expression, as well as its diagnostic significance and use as a therapeutic target in various neuroendocrine tumors. Targeting signaling pathways or gene expression alterations associated with INSM1 expression may be instrumental for the design of novel therapeutic strategies for neuroendocrine tumors.

International Union of Basic and Clinical Pharmacology. CV. Somatostatin Receptors: Structure, Function, Ligands, and New Nomenclature

Somatostatin, also known as somatotropin-release inhibitory factor, is a cyclopeptide that exerts potent inhibitory actions on hormone secretion and neuronal excitability. Its physiologic functions are mediated by five G protein-coupled receptors (GPCRs) called somatostatin receptor (SST)1-5. These five receptors share common structural features and signaling mechanisms but differ in their cellular and subcellular localization and mode of regulation. SST₂ and SST₅ receptors have evolved as primary targets for pharmacological treatment of pituitary adenomas and neuroendocrine tumors. In addition, SST₂ is a prototypical GPCR for the development of peptide-based radiopharmaceuticals for diagnostic and therapeutic interventions. This review article summarizes findings published in the last 25 years on the physiology, pharmacology, and clinical applications related to SSTs. We also discuss potential future developments and propose a new nomenclature.

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.

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.

Clinicopathological and Prognostic Evaluations of Mixed Adenoneuroendocrine Carcinoma of the Colon and Rectum: A Case-Matched Study

BACKGROUND

Mixed adenoneuroendocrine carcinoma of the colon and rectum is a very rare type of tumor.

OBJECTIVE

The aim of the present study was to evaluate the clinicopathological characteristics and prognosis of mixed adenoneuroendocrine carcinomas of the colon and rectum.

DESIGN

This was a retrospective case-matched analysis (from March 2007 to December 2013).

SETTINGS

This study was conducted at Yokosuka Kyosai Hospital.

PATIENTS

One thousand three hundred six consecutive patients with a preoperative diagnosis of colorectal cancer and who underwent tumor resection were enrolled in the present study. Each patient diagnosed with mixed adenoneuroendocrine carcinoma was 1:2 matched with 2 counterparts who had been diagnosed with adenocarcinoma.

INTERVENTION

Immunohistochemical staining for neuroendocrine markers (chromogranin A, synaptophysin, and CD56) was performed. Cases in which the neuroendocrine component accounted for >30% of the tumor were diagnosed as mixed adenoneuroendocrine carcinomas.

RESULTS

Among 1306 patients, 42 patients (3.2%) were diagnosed with mixed adenoneuroendocrine carcinoma and were compared with 84 patients with adenocarcinoma who had been randomly case matched. The average Ki-67-labeling index value was 78.0% (range, 30.0%-99.0%). Chromogranin A, synaptophysin, and CD56 positivity were observed in 42.9% (18/42), 81.0% (34/42), and 33.3% (14/42) of the tumors. Both the disease-free survival and overall survival were significantly worse for mixed adenoneuroendocrine carcinoma than for adenocarcinoma. Ten patients underwent treatment with oxaliplatin-based chemotherapy. The response rate was 40.0%; the median progression-free survival and overall survival were 6.3 months and 18.1 months.

LIMITATIONS

This was a retrospective single-institution study that included a limited number of cases. The treatment regimens used included different types of oxaliplatin-based chemotherapy.

CONCLUSION

Mixed adenoneuroendocrine carcinoma of the colon and rectum has a poor prognosis after curative resection and should be distinguished from adenocarcinoma.

Fertility sparing management of large cell neuroendocrine tumour of cervix: A case report & review of literature

Large cell neuroendocrine cervical carcinoma (LCNEC) is a rare and aggressive cancer that tends to spread and recur early despite intensive multimodal treatment. Conventional treatment strategies for early stage neuroendocrine tumour (NET) include radical hysterectomy followed by adjuvant chemotherapy. There are only 2 reported cases of fertility sparing treatment for NET. We report on the first case of successful conception and delivery at term following radical trachelectomy for early stage LCNEC.

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First reported case of delivery at term following radical trachelectomy for LCNEC

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3 year recurrence free survival following radical trachelectomy in LCNEC

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Continue data collection on both oncologic and fertility outcomes in LCNEC

A case of primary renal carcinoid tumor

Primary renal carcinoid tumors are extremely rare kidney lesions, with fewer than 100 reported cases previously. We describe a 75-year-old man with an incidentally detected cystic renal mass. Computed tomography showed a 3 cm tumor with a cystic component enhanced with contrast. No evidence of metastasis was detected. We treated the patient with radical nephrectomy. Pathological examinations revealed a cellular arrangement specific to carcinoid tumor and positive for chromogranin A, neural cell adhesion molecule, and somatostatin receptor type 2. The tumor cells had a mitotic count of 4 mitoses/10 high-power fields, and the level of the proliferation marker Ki-67 was 5%. The pathological diagnosis was renal neuroendocrine tumor grade 2. No local recurrence and no systemic metastasis were detected during the 18-month follow-up period. To our knowledge, this is the 6th case of renal neuroendocrine grade 2 tumor reported thus far.

Histopathology of gastrointestinal neuroendocrine neoplasms

Gastrointestinal neuroendocrine neoplasms (GI-NENs) arise from neuroendocrine cells distributed mainly in the mucosa and submucosa of the gastrointestinal tract. In 2010, the World Health Organization (WHO) classification of NENs of the digestive system was changed, categorizing these tumors as grade 1 neuroendocrine tumor (NET), grade-2NET, neuroendocrine carcinoma (large- or small-cell type), or mixed adenoneuroendocrine carcinoma (MANEC). Such a classification is based on the Ki-67 index and mitotic count in histological material. For the accurate pathological diagnosis and grading of NENs, it is important to clearly recognize the characteristic histological features of GI-NENs and to understand the correct method of counting Ki-67 and mitoses. In this review, we focus on the histopathological features of GI-NENs, particularly regarding biopsy and cytological diagnoses, neuroendocrine markers, genetic and molecular features, and the evaluation of the Ki-67 index and mitotic count. In addition, we will address the histological features of GI-NEN in specific organs.

Large-cell neuroendocrine carcinoma of the cervix

Large cell neuroendocrine carcinoma (LCNEC) of the uterine cervix is a rare and aggressive malignancy with poor prognosis even in its early stage, despite multimodality treatment strategy. Here, we report a case of a woman with clinical polypoid stage IB LCNEC of the cervix, which was detected in her 6-week postpartum checkup. A literature review was also conducted to evaluate current therapeutic approaches and potential new strategies.