Large cell neuroendocrine carcinoma of the kidney with cardiac metastasis: a case report

Primary large cell neuroendocrine carcinoma of the kidney is a rare and generally very aggressive disease. We present a case of a patient with primary large cell neuroendocrine carcinoma of the kidney with cardiac metastasis. A 59-year-old Japanese man presented to his previous physician with hematuria. Computed tomography revealed masses in the heart and right kidney, and fluorodeoxyglucose-positron emission tomography showed abnormal uptake in the heart. A cardiac biopsy under transesophageal echocardiographic guidance revealed a metastatic tumor. Subsequently, multiple lung lesions were detected, and a right nephrectomy was performed after these metastases were suspected to have originated from renal carcinoma. Large cell neuroendocrine carcinoma of the kidney was ultimately diagnosed. Pancreatic metastasis was detected on computed tomography postoperatively. Three courses of chemotherapy with carboplatin and irinotecan were administered, and were temporarily effective against the metastatic lesions in the lungs and pancreas. However, our patient's general condition deteriorated with the progression of the lesions, and he died 9 months after his initial examination. Multi-agent chemotherapy, including platinum-based drugs was effective against large cell neuroendocrine carcinoma metastases, albeit only temporarily. This is the first reported case of large cell neuroendocrine carcinoma with cardiac metastasis.