Neuroendocrine features in poorly differentiated endometrioid adenocarcinomas of the endometrium

Endometrial neuroendocrine carcinoma and undifferentiated carcinoma are distinct entities with overlap in neuroendocrine marker expression

AIMS

Dedifferentiated/undifferentiated endometrial carcinomas (DDEC/UDEC) frequently harbor genomic activation of SWItch/Sucrose Non-Fermentable (SWI/SNF) complex proteins, and can show histologic overlap with neuroendocrine carcinoma (NEC). This study compares the expression of neuroendocrine markers, SWI/SNF proteins and mismatch repair (MMR) proteins in DDEC/UDEC and NEC.

METHODS AND RESULTS

The expressions of synaptophysin, chromogranin, CD56, ARID1A, ARID1B, SMARCA4, SMARCB1 and MMR proteins were evaluated by immunohistochemistry on 44 SWI/SNF-deficient DDEC/UDEC and 15 NEC. 33 of 44 (75%) DDEC/UDEC showed expression of at least one neuroendocrine marker with 18 of 44 (41%) expressing 2 or more neuroendocrine markers, whereas all 15 NEC showed expression of at least one neuroendocrine marker with 14 of 15 (93%) expressing 2 or more neuroendocrine markers. Neuroendocrine marker expression in DDEC/UDEC was typically focal when present, with an average extent of 17%, 4% and 8% for synaptophysin, chromogranin and CD56 in the positive cases respectively, in contrast to 73%, 40% and 62% in the positive NEC cases respectively. All 15 NEC showed intact expression of SWI/SNF proteins except for 1 that showed isolated loss of ARID1A. 38 of 44 DDEC/UDEC were MMR-abnormal (34 with loss of MLH1 and PMS2, 4 with loss of PMS2 alone) whereas all NEC retained MMR protein expression.

CONCLUSIONS

Our study demonstrates frequent but typically focal neuroendocrine marker expression in SWI/SNF-deficient DDEC/UDEC, while NECs typically express 2 or more neuroendocrine markers with diffuse expression in at least one marker. ARID1B, SMARCA4 and SMARCB1 immunohistochemistry can be used to aid differentiation between DDEC/UDEC and NEC.

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.

Mixed Neuroendocrine-Nonneuroendocrine Neoplasms (MiNENs): Unifying the Concept of a Heterogeneous Group of Neoplasms

The wide application of immunohistochemistry to the study of tumors has led to the recognition that epithelial neoplasms composed of both a neuroendocrine and nonneuroendocrine component are not as rare as traditionally believed. It has been recommended that mixed neuroendocrine-nonneuroendocrine epithelial neoplasms are classified as only those in which either component represents at least 30 % of the lesion but this cutoff has not been universally accepted. Moreover, since their pathogenetic and clinical features are still unclear, mixed neuroendocrine-nonneuroendocrine epithelial neoplasms are not included as a separate clinicopathological entity in most WHO classifications, although they have been observed in virtually all organs. In the WHO classification of digestive tumors, mixed neuroendocrine-nonneuroendocrine neoplasm is considered a specific type and is defined as mixed adenoneuroendocrine carcinoma, a definition that has not been accepted for other organs. In fact, this term does not adequately convey the morphological and biological heterogeneity of digestive mixed neoplasms and has created some misunderstanding among both pathologists and clinicians. In the present study, we have reviewed the literature on mixed neuroendocrine-nonneuroendocrine epithelial neoplasms reported in the pituitary, thyroid, nasal cavity, larynx, lung, digestive system, urinary system, male and female genital organs, and skin to give the reader an overview of the most important clinicopathological features and morphological criteria for diagnosing each entity. We also propose to use the term "mixed neuroendocrine-nonneuroendocrine neoplasm (MiNEN)" to define and to unify the concept of this heterogeneous group of neoplasms, which show different characteristics mainly depending on the type of neuroendocrine and nonneuroendocrine components.

Long-term survival in small-cell carcinoma of the endometrium with liver and brain metastases

Small-cell carcinoma (SmCC) of the endometrium is an extremely rare cancer and has a poor prognosis. Because long-term survival is rare, there is a paucity of data on the advanced disease stages. Thus, a standard treatment has not been established. We describe an extremely rare case of long-term survival in SmCC of the endometrium with liver and brain metastases. We provided multidisciplinary treatment, including brain surgery, subsequent whole-brain radiotherapy, gynecologic surgery, and adjuvant chemotherapy (irinotecan hydrochloride+cisplatin). The patient was treated successfully and has survived for more than 12 years with no evidence of the disease. Irinotecan hydrochloride+cisplatin chemotherapy was effective for controlling the liver metastases, and the resection of brain metastases and radiotherapy were effective for the treatment of brain metastases in our case. We reviewed the pertinent literature of advanced SmCC of the endometrium.

Metastatic large cell neuroendocrine carcinoma of the lung arising from the uterus: A pitfall in lung cancer diagnosis

A 41-year-old female smoker presented with a vaginal mass. Gynecological examination showed a mass filling the uterine corpus, cervix, and vagina. A total abdominal hysterectomy was performed. Macroscopic findings included a large fragile mass involving the uterine cavity, cervix, and vagina. Histology revealed atypical ducts admixed with solid components consisting of large atypical cells. The initial pathological diagnosis was grade 3 endometrioid adenocarcinoma. The patient was designated as stage II according to the 2008 International Federation of Gynecology and Obstetrics (FIGO) staging. Two years later, two nodules were found in the upper lobe of the left lung, and the patient underwent an upper lobectomy. The masses, which exhibited solid and organoid growth patterns of large atypical cells, had histological characteristics of large cell neuroendocrine carcinoma (LCNEC) of the lung. However, the tumor was immunohistochemically positive for neuroendocrine markers, such as synaptophysin in addition to estrogen receptor and progesterone receptor, and the tumor was negative for thyroid transcription factor-1. These immunohistochemical results were almost identical to those of the solid portions of the uterine carcinoma. The final diagnosis was LCNEC combined with endometrioid adenocarcinoma of the uterine corpus and lung metastasis of the LCNEC component of the endometrial carcinoma. LCNEC often arises in the lung, but it rarely arises in other organs. Some patients with metastatic components exhibited only a LCNEC pattern although the primary tumor was a mixed carcinoma consisting of LCNEC and other histology, like the present case. LCNEC is often poorly differentiated, especially in extrapulmonary primary organ LCNEC. Therefore, pathologists should consider metastatic carcinoma when they encounter lung LCNEC in a patient with a preceding extrapulmonary carcinoma composed of a poorly differentiated component or LCNEC component, and they should clarify tumor immunohistochemical characteristics to confirm the diagnosis.

Neuroendocrine Tumors of the Female Reproductive Tract: A Literature Review

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

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

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

Clinicopathologic significance of gastric adenocarcinoma with neuroendocrine features

PURPOSE

Composite neuroendocrine-exocrine carcinomas are malignancies that have two distinct components residing within the same tumor: an adenocarcinomatous portion and a neuroendocrine portion. This is rare in gastric cancers; however, poorly differentiated adenocarcinomas can sometimes reveal evidence of neuroendocrine features (NEF) or be 'mixed endocrine and exocrine carcinomas'. This study aimed to review NEF in gastric adenocarcinoma and to evaluate its prognostic significance.

MATERIALS AND METHODS

We selected 29 patients who were diagnosed with gastric adenocarcinoma with NEF and received gastrectomies at the Department of Surgery, Ajou University Hospital between January 2001 and December 2009. We analyzed the clinicopathologic features of gastric cancer with NEF and the prognosis associated with such tumors.

RESULTS

THE PATHOLOGIC RESULT WITH RESPECT TO TNM STAGING OF THE GASTRIC CANCERS WITH NEF WERE AS FOLLOWS: 5 cases of T1, 5 cases of T2, 10 cases of T3, and 9 cases of T4. There were 7 cases of N0, 7 cases of N1, 8 cases of N2 and 7 cases of N3. The staging of patients with NEF was higher than that of patients without NEF. Especially tumor lymphovascular invasion rate was 82.8%. The overall survival of patients with gastric cancer characterized by NEF was 73.8 months.

CONCLUSIONS

Positive NEF status might be correlated with clinicopathologic parameters such as a high stage and high frequency of regional lymph node metastasis.

The significance of neuroendocrine expression in undifferentiated carcinoma of the endometrium

Carcinomas with neuroendocrine (NE) differentiation have been associated with poor outcome in different organs. The purpose of this study was to evaluate the presence and significance of NE expression in a series of 46 undifferentiated endometrial carcinomas diagnosed between 1988 and 2005. NE expression was studied by immunohistochemistry including synaptophysin, chromogranin, and/or CD56. The patients' age ranged from 30 to 84 years (mean 55). Staging information was available for 45 cases and according to the International Federation of Gynecology and Obstetrics system they were distributed as follows: stage I (9 cases), stage II (2 cases), stage III (9 cases), and stage IV (25 cases). NE expression was present in 19/46 (41%) cases; however, it was diffuse in only 9% of the tumors. The median survival for patients without NE expression was 7 months (95% confidence interval 4-10 mo) and for patients with NE expression was 12 months (95% confidence interval 6-27 mo). The survival curves do not differ significantly (P=0.49). NE expression is common in undifferentiated carcinoma of the endometrium, as it was found in 41% of our cases. In most cases, NE expression is only focally present (< or =10% of the cells). There is no difference in overall survival in patients with or without NE expression.

Combined large cell neuroendocrine carcinoma and papillary serous carcinoma of the endometrium with pagetoid spread

Neuroendocrine carcinomas of the endometrium are rare tumors that can be pure, combined with endometrioid adenocarcinoma, or a component of malignant mixed müllerian tumor. Recently, a case of combined small cell carcinoma and papillary serous carcinoma of the endometrium was described for the first time. We report the first case, to our knowledge, of combined large cell neuroendocrine carcinoma and papillary serous carcinoma of the endometrium, with an unusual pagetoid spread of the neuroendocrine component into normal endometrial and endocervical glands. The endometrial carcinoma had a small serous component, but most of the tumor was characterized by solid sheets of medium to large cells with abundant mitotic figures, numerous apoptotic bodies, and foci of necrosis. This component was diffusely positive for neuroendocrine markers. Following surgery, the patient was treated with radiation therapy and chemotherapy. She was without evidence of progression at 5 months of follow-up.

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.