Available reports of synchronous prostate and bladder cancer have exclusively described radical cystoprostatectomy with or without perioperative chemotherapy as the treatment of choice. There are no reports of curative intent or definitive chemoradiation therapy for synchronous primary bladder and primary prostate cancers. Small cell carcinoma of the bladder is a rare and aggressive tumor. We present the first case of synchronous mixed small cell carcinoma and urothelial carcinoma of the urinary bladder and adenocarcinoma of the prostate in a 70-year-old male who attained long-term survival after curative intent and definitive concurrent chemoradiotherapy with minimal acute and late toxicities. The patient remained alive and disease-free at 41 months post-treatment and achieved excellent functional outcomes with organ preservation. Definitive chemoradiation therapy offers a safe and effective, curative-intent organ preservation treatment for localized synchronous prostate and bladder cancers.

Malignancies with unknown primaries contribute to a small yet significant percentage of overall tumors. Neuroendocrine carcinomas, a rare disease with a poor prognosis, have been known to present as an unknown primary. Treatment consists of cytotoxic chemotherapy but given the latter\'s high toxicity profile new treatment options are being explored. In this case report, we describe a case of a patient with poorly differentiated neuroendocrine carcinoma of unknown primary treated with compassionate oral everolimus after his refusal of intravenous chemotherapy.

Colon cancer is one of the most common diagnoses of cancer and a leading cause of death in America. Large cell neuroendocrine tumors are a very uncommon type of colon cancer that tends to have a poor prognosis. Usually, these tumors are only found at the time of metastasis making them even more difficult to treat. A 65-year-old female presented with worsened generalized abdominal pain associated with abdominal distention. She had not had a bowel movement in over a week and did not have any flatulence. She had a colonoscopy four years prior that was normal. Physical examination was significant for abdominal distention and a large right-sided palpable mass in her abdomen with generalized tenderness. A CT scan showed a large irregular mass at least 9.8 x 10.5 cm at the mid to distal ascending colon resulting in significant colonic narrowing significant for a large bowel obstruction. The CT also demonstrated suspicious nodules in the lung, lesions in the liver, and lymphadenopathy. She had an exploratory laparotomy with an extended hemicolectomy to remove the mass. Pathology revealed the mass was neuroendocrine carcinoma, a large cell subtype, that was poorly differentiated with involvement of at least 32 of 34 lymph nodes. This tumor was positive for AE1/AE3, CEA, CK20, and synaptophysin. Ki-67 showed 70% positivity. TTF1 was negative and ruled out a primary lung tumor. Microsatellite immunostains were positive for MLH-1, MSH-2, MSH-6, and PMS2. The patient was started on Carboplatin AUC6 and Etoposide 100mg/m2 in three-week intervals. Pegfilgrastim was also added to her treatment plan every 21 days. This is a review of a female who presented with colonic obstruction that was found to be poorly differentiated large cell neuroendocrine carcinoma after a previous negative colonoscopy.

The aim of the present study was to integrate the available data published in the literature on oral and maxillofacial neuroendocrine carcinomas concerning the demographic, clinical and histopathological features of this condition. An electronic search with no publication date restriction was undertaken in April 2021 in four databases. Eligibility criteria included reports published in English having enough data to confirm a definite diagnosis, always showing a neuroendocrine marker. Cases originating in the oropharynx, including base of the tongue and tonsils, were excluded. Outcomes were evaluated by the Kaplan-Meier method along with Cox regression. Twenty-five articles (29 cases) from nine different countries were detected. Mean patient age was 56.3 (± 17.5) years, with a slight male predilection. Symptomatology was present in 72.2% of informed cases. Regarding clinical presentation, a non-ulcerated nodule located in the gingiva with a mean size of 3.4 (± 2.0) cm was most frequently reported. Concomitant metastasis was identified in seven individuals. Histopathologically, most neoplasms were of the small cell type, and immunohistochemistry for both epithelial and neuroendocrine differentiation was used in 65.5% cases. Radical surgery was the treatment of choice in almost all cases, with or without adjuvant therapy. Mean follow-up was 20.5 (± 21.2) months, and only four patients developed recurrences. Eleven (44.0%) individuals died due to the disease. Ulcerated lesions were a prognostic factor. This study provides knowledge that can assist surgeons, oncologists, and oral and maxillofacial pathologists with the diagnosis and management of neuroendocrine carcinomas. Our findings demonstrated that the long-term prognosis of this lesion continues to be poor.

Primary neuroendocrine tumors (NETs) of the liver are rare and difficult to distinguish from other liver tumors such as cholangiocarcinoma and hepatocellular carcinoma. The patient was initially diagnosed with a NET of the liver in 2007. However, the origin of the cancer was not clear, that is, whether it was primary or originated from the gastrointestinal tract. Although the patient underwent partial hepatectomy, he suffered hepatic artery injury, resulting in biliary strictures. The patient eventually became untreatable and developed cirrhosis, a frozen abdomen. He received multivisceral transplantation in May 2019 and received the liver, duodenal-pancreatic complex, spleen, small bowel, and right colon. After the transplantation, the patient did well overall. More recently, he presented with food poisoning and underwent evaluation, and was found to have a mass in the liver. The liver mass was biopsied and revealed a poorly differentiated primary NET (grade 2) with ciliated papillary structures.

Sinonasal teratocarcinosarcoma (SNTCS) is a rare, aggressive malignancy that displays a heterogeneous combination of malignant blastema-like, epithelial and mesenchymal components. Its exact histogenesis is unknown with hypotheses ranging from true germ cell derivation to origin from pluripotent stem cells. However, despite this tumor\'s multiphenotypic histology, which includes frequent glandular, squamous, and neuroectodermal differentiation similar to adnexal germ cell tumors, SNTCS appears to have some differences from adnexal teratomas. For example, unlike adnexal teratomas, SNTCS has never been described as a component in a mixed germ cell tumor. Accurate recognition of SNTCS is difficult due to its rarity and histologic overlap with other sinonasal tumors. It is even more problematic on biopsy, since not all elements may be present in small samples. SNTCS can also share similar staining patterns with other neoplasms in the differential diagnosis. A recent study found nuclear β-catenin expression in a single TCS, but this has yet to be confirmed in additional cases. SALL-4, a marker of germ cell tumors, has not been examined. We performed β-catenin and SALL-4 immunohistochemistry on whole sections of 7 SNTCS and 19 other sinonasal neoplasms to assess whether β-catenin and SALL-4 are of utility in establishing a diagnosis of SNTCS. Intensity of expression and percentage of staining was noted for each tumor. For SNTCS, distribution of staining within each histologic component (immature neuroectodermal, epithelial, and mesenchymal) was also documented. Nuclear β-catenin expression was not identified in any SNTCS, with all cases demonstrating membranous expression (6 cases) or cytoplasmic and membranous expression (1 case). SALL-4 immunohistochemistry, however, was relatively sensitive (85.7%) and specific (89.5%) for SNTCS. SALL-4 expression was also identified in one poorly differentiated neuroendocrine carcinoma and one case of sinonasal undifferentiated carcinoma. SALL-4 appears to have utility in distinguishing SNTCS from other high grade sinonasal tumors.

Introduction Neuroendocrine neoplasms (NENs) are a heterogeneous group of tumors with histological features varying from well-differentiated neuroendocrine tumors (WDNETs) to poorly differentiated neuroendocrine carcinomas (PDNECs). In this study, we investigated the clinicomorphological spectrum of NENs including tumor grade, site of origin, and metastasis. Methods We retrospectively studied 125 cases of NENs (at the Department of Histopathology, Liaquat National Hospital and Medical College, Karachi) between the years 2014 and 2020. Slides of these cases were retrieved from the departmental archives and were evaluated for the tumor type, grade, and site of origin. Results The mean age of the patients was 51.25±16.10 years. Overall, the liver was the most common site of the tumor (27.2%), followed by the small bowel (15.2%). Grade 2 was the most common tumor grade (40.8%), and most of the tumors were primary (68.8%). A total of 84.8% of the tumors were WDNETs/carcinoids, while 15.2% were PDNEC. The small bowel was the most common site of primary NENs, followed by the stomach and lung. Among primary neuroendocrine tumors, patients with PDNEC were significantly noted to have a higher mean age than WDNET/carcinoid. Similarly, PDNEC had a higher ki67 index than WDNET/carcinoid. For metastatic NENs, the liver was the most common site of metastasis (71.8%) with the GI/pancreatobiliary tract being the most common primary site of origin (51.3%). Tumors with primary lung origin were found to have a higher tumor grade than primary GI/pancreatobiliary tract origin NENs (p<0.0001). Conclusion In this study, we found that the small intestine and liver were the most common sites for primary and metastatic NENs, respectively. Moreover, primary PDNECs were associated with a higher mean age than WDNETs. Alternatively, metastatic NENs with primary lung origin had a higher tumor grade than primary GI/pancreatobiliary tract origin.

Neuroendocrine neoplasms (NENs) of the gastrointestinal (GI) tract and pancreas are a rare and heterogeneous group of neoplasms characterized by common cellular features as well as unique site-specific traits. GI and pancreatic NENs are much rarer than the more common adenocarcinomas arising at these sites. However, the incidences of GI and pancreatic NENs have increased significantly, particularly in the stomach and common site, followed by rectum, appendix, colon, and stomach. Pancreatic NENs are also uncommon, with fewer than 1 per 100,000, accounting for 1% to 2% of all pancreatic neoplasms.

Neuroendocrine tumors (NETs) constitute a heterogeneous group of neoplasms with distinct biological behaviors, depending on the site of origin and the degree of tumor proliferation. Although advances in biochemical and radiological modalities have enhanced the ability to detect NETs, tissue diagnosis remains the gold standard to assess tumor characteristics for treatment decision making. In an era with growing demands for precision diagnostics based on smaller tissue samples, immunohistochemistry has become an indispensable tool in the pathologist\'s repertoire. In conjunction with clinical findings and cytomorphology, complementary use of 1) markers of neuroendocrine differentiation, 2) markers confirming epithelial nature, 3) markers of cellular proliferation, 4) transcription factors and hormonal markers, as well as 5) predictive and prognostic markers may be necessary to guide patient management in NETs. The current review summarizes common applications of these immunohistochemical markers when confronted with a potential neuroendocrine neoplasm, and proposes a stepwise algorithmic approach to avoid diagnostic errors in targeted biopsies. Cancer Cytopathol 2016;124:871-884. © 2016 American Cancer Society.

BACKGROUND: Primary gastric small cell carcinomas (GSCCs) are increasingly identified by endoscopy, and account for 15-20% of all gastric neuroendocrine tumors (NETs). GSCCs have the worst prognosis with the highest rate of metastases.
OBJECTIVE: To provide useful information for clinicians and researchers to better manage patients with GSCC, we studied the clinical features of GSCC and explored the corresponding therapies and prognosis.
METHODS: A literature search was conducted through PUBMED, EMBASE, CNKI and WanFang Databases using search terms \"stomach\" or \"gastric\" and \"small cell carcinoma\" or \"poorly differentiated neuroendocrine carcinoma\", for the period 1999 to 2012. And the cases reported were all from China. Relevant articles were identified through manual review. The reference lists of these articles were reviewed to include further appropriate articles.
RESULTS: Two hundred and five eligible cases were analyzed. The median age of patients was 62 years, with a male-to-female ratio of 5.4:1. Of the tumors, 53.17% were located in the upper stomach, 25.37% in the mid, 18.54% in the distal stomach, the remaining 2.93% were found in the total stomach. The mean size was 68mm in maximum diameter, with a range of 15-150 mm. Of the one hundred and thirty-five patients, fifty appeared to be pure GSCCs, eighty-five were mixed. The median overall survival time of 195 patients was 18.50 months. The 1-, 2-, and 5-year average survival rates of 142 patients were 66.75%, 37.13%, and 20.15%, respectively.
CONCLUSIONS: GSCC is a rare tumor and it is notoriously aggressive with a strong propensity for both regional and distant spread. Therapies including surgical resection, chemotherapy, and local radiotherapy, by itself or in combination with other treatment, have been used to treat GSCCs in China. To identify the most effective treatment modalities for GSCCs, we still need prospective, multicenter, randomized clinical researches.