ABSTRACT
In contrast with the large amount of data generated from endocrine tumors of the pancreas, sparse and mostly unconfirmed data are available on the criteria for the assessment of malignancy risk and patient outcome in endocrine tumors of the gastrointestinal tract. In these conditions the 2000 WHO classification with its standardized scheme of pathologic report constitutes a framework facilitating the assessment of tumor malignancy and has been regarded as useful for clinical purposes, providing the basis for proper management of the patients and for the design of treatment protocols. The classification is based on a combination of pathological and clinical features with parameters specific for each organ in which the endocrine tumors originate. Three main categories, one further subdivided into two subgroups, are considered: (1) well-differentiated endocrine tumors, further subdivided into tumors with benign and with uncertain behavior; (2) well-differentiated endocrine carcinomas, low grade; and (3) poorly differentiated endocrine carcinomas, high grade. In this review the differential tumor characteristics between the different categories are summarized. Moreover, the relevance of additional features with respect to tumor prognostication, chiefly the Ki-67 proliferation index and malignancy-associated genetic changes, is discussed with emphasis on the discrepancies emerging between tumors of foregut and of midgut origin.
Subject(s)
Endocrine Gland Neoplasms/classification , Endocrine Gland Neoplasms/diagnosis , Gastrointestinal Neoplasms/classification , Gastrointestinal Neoplasms/diagnosis , Neoplasm Invasiveness/diagnosis , Biomarkers, Tumor/analysis , Diagnosis, Differential , Endocrine Gland Neoplasms/pathology , Gastrointestinal Neoplasms/pathology , Humans , Ki-67 Antigen , Mitotic Index , Neoplasm Invasiveness/genetics , Neoplasm Invasiveness/pathology , Prognosis , World Health OrganizationABSTRACT
BACKGROUND: A fatal pulmonary tumor microembolism is rarely caused by an occult gastric cancer. METHODS AND RESULTS: We report the case of a 40-year-old woman who died after 3 days of progressive dyspnea, cough, and pulmonary hypertension. Postmortem examination demonstrated the presence of an occult diffuse-type gastric carcinoma, which had caused emboli in about 80% of small pulmonary arteries and arterioles. Despite an interatrial defect in the fossa ovalis, no parenchymal metastases were documented. CONCLUSION: Pulmonary tumor microembolism may be suspected in patients complaining of unexplained progressive dyspnea and who develop acute or subacute cor pulmonale.
