Metastatic neuroendocrine carcinoma of the spleen: a case report and review of the literature

Objective: To investigate the clinicopathological features,diagnosis and differential diagnosis for metastatic neuroendocrine carcinoma of the spleen. Methods: Paraffin imbedding section,morphological observation and immunohistochemistry,with analysis of clinical manifestation and imaging data,were applied in one case of metastatic neuroendocrine carcinoma of the spleen,and the related literatures were reviewed. Results: A 30-year-old male presented lassitude, fever, pain in the left upper quadrant, moderate splenomegaly,splenic rupture. Colored Doppler and computed tomography showed space-occupying lesions in the spleen. Pathologic features:tumor cells were located in splenic pulp around splenic spontaneous rupture site and mass in hilum of spleen. Tumor cells were arranged in sheets or in trabs or in glandular cavity or in pseudo-rosettes,and were separated with fibrous stroma. The tumor cells were moderate size and relatively uniform,with abundant eosinophilic cytoplasm and round or orbicular-ovate nuclei with prominent nucleoli. Few pathological karyokinesis was observed. Lymph nodes in hilum of spleen and blood vessel were also invaded. The tumor cells were strongly positive for CD56,poorly positive for Syn,CgA and CK. Conclusions: Metastatic neuroendocrine carcinoma of the spleen is extremely rare. The morphology is quite similar to the neuroendocrine carcinoma in other organs,and immunohistochemistry is helpful in the diagnosis. Cooperation of clinicians and pathologists may enhance the diagnostic level.