Combined Positive Score for Programmed Death Ligand-1 Expression and Inflammatory Microenvironment in Gastrointestinal Stromal Tumors.

Background and Objectives: GISTs are the most frequent type of mesenchymal neoplasm of the digestive tract. The prognosis is mainly determined by tumor dimensions, mitotic rate and location, but other less well-documented factors can influence evolution and survival. The immune microenvironment and checkpoint molecule expression were proven to impact the prognosis in different types of cancer. The aim of this study was to determine PD-L1 expression in GISTs and to evaluate the level of intratumoral immune infiltration in relation to prognostic variables and survival. Materials and Methods: Sixty-five GISTs diagnosed in the same institution between 2015 and 2018 were immunohistochemically tested for PD-L1 and evaluated using CPS. Immune cells were emphasized, with CD3, CD4, CD8, CD20 and CD68 antibodies and quantified. All data were processed using statistical tools. Results: The median age was 61 years (range, 28-78) and 36 patients (55.4%) were males. The location of the tumors was predominantly gastric (46%), followed by the small bowel (17%) and colorectal (6%). In addition, 11% were EGISTs and 20% were secondary tumors (11% metastases and 9% local recurrences). PD-L1 had a variable expression in tumor and inflammatory cells, with a CPS ranging from 0 to 100. Moreover, 64.6% of cases were PD-L1 positive with no significant differences among categories of variables, such as the age and the sex of the patient, tumor location, the primary or secondary character of the tumor, dimensions, mitotic rate, the risk of disease progression and tumor cell type. Immune cells had a variable distribution throughout the tumors. CD3+ lymphocytes were the most frequent type. CD20+ cells were identified in a larger number in tumors ≤5 cm (p = 0.038). PD-L1-positive tumors had a higher number of immune cells, particularly CD3+, CD20+ and CD68+, in comparison to PD-L1-negative ones (p = 0.032, p = 0.051, p = 0.008). Epithelioid and mixed cell-type tumors had a higher number of CD68+ cells. Survival was not influenced by PD-L1 expression; instead, it was decreased in multifocal tumors (p = 0.0001) and in cases with Ki67 ≥ 50% (p = 0.008). Conclusions: PD-L1-positive expression and the presence of different immune cell types, in variable quantities, can contribute to a better understanding of the complex interactions between tumor cells and the microenvironment, with a possible therapeutic role in GISTs.

An unusual presentation of a carcinoid tumor of the common bile duct.

CONTEXT: Carcinoid tumors arising from the bile ducts account for only a small fraction of biliary tract cancers. CASE REPORT: We report herein a 42-year-old man with a carcinoid tumor of the common bile duct. He presented with abdominal pain, bloating and dyspepsia. Clinicolaboratory and imaging studies suggested a probable obstructive common bile duct lesion. The patient underwent an endoscopic retrograde cholangiopancreatography with a stent placement in view of common bile duct decompression. Persistence of symptoms prompted a laparotomy and pancreaticoduodenectomy that revealed a well-differentiated carcinoid tumor originating in the common bile duct. CONCLUSION: Clinician's familiarity with the unusual sites of origin of neuroendocrine tumors and/or atypical presentation of such tumors may facilitate their early recognition and allow for a timely intervention.

Pathological characteristics and clinical specifications in gastroenteropancreatic neuroendocrine tumors: a study of 68 cases.

INTRODUCTION: Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) represent a group of tumors, having their origin in cells of diffuse endocrine system, with particular clinical course, diagnosis and treatment. PATIENTS AND METHODS: In our study, were included 68 patients with neuroendocrine digestive tumors admitted, diagnosed and treated in Fundeni Clinical Institute, Bucharest, in the last ten years--2000-2010 (retrospective study). RESULTS: Thirty-three (49%) patients were males, 35 (51%) females, and the main age was 58.9 years. In 62 (90.3%) cases was possible to find the primary tumor. The examined tumors had different localizations: pancreas--32 (47.04%) cases (head--17 (24.99%) cases, and body and tail--15 (22.05%) cases), stomach--7 (10.29%) cases, small intestine--7 (10.29%) cases, 6 (8.82%) cases--unknown primary site (diagnosis was established on metastases), right colon--6 (8.82%) cases, liver--6 (8.82%) cases, rectum--2 (2.94%) cases, and retroperitoneum--2 (2.94%) cases. Microscopic examination revealed 59 (86.8%) malignant tumors and 9 (13.2%) benign tumors. Using WHO 2000 Classification, 28 cases of malignant tumors were well-differentiated neuroendocrine carcinomas, and 31 cases were poor differentiated neuroendocrine carcinomas. From malignant cases, 25 (42.3%) have distant metastases and 15 (25.9%) lymph node metastases. CONCLUSIONS: Cases of gastroenteropancreatic neuroendocrine tumors included in our study had clinical and histopathological features in correspondence with data from literature--slight predominance in women, predominance in 5th and 6th decades of life, the most frequent localizations were at pancreatic level--both head and body and tail, but the rarest were in colon and retroperitoneum. Most of the cases studied, were malignant tumors, from these more than a half were poor differentiated, and a quarter of them having lymph node or distant metastases.

Functional 'composite' pheochromocytoma-ganglioneuroma presenting as a pancreatic mass.

Pheochromocytomas rarely have 'composite' forms in which they demonstrate histologic features of a typical paraganglioma in combination with those of a neural component. Extra-adrenal 'composite' pheochromocytomas are distinctly uncommon. We describe herein a unique case of a 34-year-old female patient with type 1 neurofibromatosis who presented with abdominal pain and paroxysmal hypertension. Imaging revealed a pancreatic mass with biliary and pancreatic ductal dilatation and a hormonal assay led to the diagnosis of functional pheochromocytoma. She underwent surgical resection and histopathology revealed a composite paraganglioma-ganglioneuroma. Clinical, biochemical and radiological aspects of this rare tumor and its association with neurofibromatosis and other hereditary cancer syndromes are discussed.

Emerging therapeutic options for advanced enteropancreatic neuroendocrine tumors.

INTRODUCTION: Several chemotherapy agents and combinations have proven effective in the therapy of advanced enteropancreatic neuroendocrine tumors (EP-NETs). However, their toxicity can be significant. Recent understanding of the molecular mechanisms of these tumors, especially the central role of tumor angiogenesis, has led to the identification of new therapeutic targets and agents directed at the molecular level. AREAS COVERED: This paper gives a comprehensive evaluation of the existing therapeutic armamentarium for EP-NETs. Narrated in a historical perspective, this review analyzes the available information on traditional chemotherapy agents, interferon-α and somatostatin analogs, as well as newer therapies and experimental agents. EXPERT OPINION: Despite recent advances, a curative approach for metastatic EP-NETs is yet to be discovered. To date, sunitinib and everolimus have been shown to impact progression-free survival only in pancreatic NETs, and the duration of this benefit has not yet been established. Further research is necessary to determine whether a combination of these drugs, either together or with other therapies, may yield superior outcomes. Moreover, sequential use of these agents should be explored in an attempt to improve survival. Efficacy of a variety of experimental agents is also being tested in clinical trials.