Rare Case of High Grade Neuroendocrine Carcinoma Found on Bone Marrow Biopsy: A Case Report.

BACKGROUND

Neuroendocrine neoplasms (NENs) comprise a wide-ranging group of abnormal neoplasms with atypical presentations, from primary localized disease to extensive metastasis, reaching the bone and brain. The NENs are divided into two major groups: neuroendocrine tumors (NETs), which are well-differentiated tumors of any grade, and neuroendocrine carcinomas (NECs), which are poorly differentiated, high-grade cancers with a high risk of morbidity and mortality. The challenge of diagnosing NENs early, particularly prior to metastasis, highlights the importance of further studying these diseases. We present a case of aggressive metastatic neuroendocrine carcinoma of a gastrointestinal/pancreaticobiliary origin.

CASE SUMMARY: A 54-year-old male with a past medical history of hypertension and left total hip replacement presented with generalized weakness, dyspnea on exertion, decreased appetite, and fatigue for one month. Initial laboratory findings noted a hemoglobin level of 3.1 g/dL and a platelet count of 9 × 109/L. CT scan findings revealed a splenic infarct, lytic bone lesions, and small bilateral occipital hemorrhages. Bone marrow biopsy was consistent with metastatic, high-grade, poorly differentiated neuroendocrine carcinoma favoring a gastrointestinal/pancreaticobiliary origin. The patient expired shortly after starting chemotherapy due to the extensive disease.

CONCLUSION

Neuroendocrine neoplasms may be discovered late in their course with distant metastatic spread and thus have a poor prognosis. This case report and literature review describes the presentation of metastatic high-grade neuroendocrine carcinoma in a patient presenting to a community hospital, and reviews the current literature and guidelines on neuroendocrine carcinomas.