Nguyen Duy T, Nguyen Hoang X, Hoang Phuc T
Department of Urology, Binh Dan Hospital, Ho Chi Minh, VNM.
Cureus. 2025 Jun 10;17(6):e85693. doi: 10.7759/cureus.85693. eCollection 2025 Jun.
Primary renal neuroendocrine tumors (NETs) are exceedingly rare. Among these, small cell neuroendocrine carcinoma (SCNC) represents an aggressive and poorly differentiated subtype, with very few documented cases. We present a case of a 24-year-old male patient who presented with gross hematuria and flank pain. Imaging revealed a large right renal mass with a tumor thrombus extending into the inferior vena cava (IVC). The patient underwent radical nephrectomy, adrenalectomy, and IVC thrombectomy. Histopathological examination confirmed a high-grade small cell neuroendocrine carcinoma with extensive necrosis and vascular invasion. Immunohistochemistry was positive for CD56, synaptophysin, and a high Ki-67 index (~70%). Despite radical surgery and systemic chemotherapy with carboplatin and etoposide, the patient developed liver metastases within three months and succumbed to disease progression nine months postoperatively. This case underscores the rarity and aggressive nature of primary renal SCNC, the clinical significance of IVC tumor thrombus as a poor prognostic factor, and the rapid disease progression that can occur even in young patients. Multimodal therapy remains the mainstay of treatment, but the overall prognosis is poor. Further investigation into molecular characteristics and targeted therapies is urgently needed.
原发性肾神经内分泌肿瘤（NETs）极为罕见。其中，小细胞神经内分泌癌（SCNC）是一种侵袭性强且分化差的亚型，仅有极少病例记载。我们报告一例24岁男性患者，其表现为肉眼血尿和侧腹痛。影像学检查显示右肾有一巨大肿块，肿瘤血栓延伸至下腔静脉（IVC）。该患者接受了根治性肾切除术、肾上腺切除术及IVC血栓切除术。组织病理学检查证实为高级别小细胞神经内分泌癌，伴有广泛坏死和血管侵犯。免疫组化显示CD56、突触素阳性，Ki-67指数高（约70%）。尽管进行了根治性手术及卡铂和依托泊苷的全身化疗，但患者在三个月内出现肝转移，并于术后九个月因疾病进展死亡。该病例凸显了原发性肾SCNC的罕见性和侵袭性、IVC肿瘤血栓作为不良预后因素的临床意义，以及即使是年轻患者也可能出现的快速疾病进展。多模式治疗仍是主要治疗方法，但总体预后较差。迫切需要对分子特征和靶向治疗进行进一步研究。
