Catena Laura, Bichisao Ettore, Milione Massimo, Valente Monica, Platania Marco, Pusceddu Sara, Ducceschi Monika, Zilembo Nicoletta, Formisano Barbara, Bajetta Emilio
Oncologia Medica 2, Fondazione IRCCS Istituto Nazionale Tumori, Via G. Venezian 1, 20133 Milan, Italy.
Tumori. 2011 Sep-Oct;97(5):564-7. doi: 10.1177/030089161109700504.
Neuroendocrine tumors of an unknown primary site are rarer than other neuroendocrine tumors (0.6-2% of all neuroendocrine tumors) and have a poor prognosis. The aim of the study was to review the cases of unknown primary site neuroendocrine tumors encountered at the Istituto Nazionale Tumori of Milan between 1984 and 2008 in order to verify their incidence and evaluate their characteristics and prognosis.
During the study period, 750 neuroendocrine tumor patients attended our Institute, 82 of whom (10.9%) were diagnosed as having neuroendocrine tumors of an unknown primary site. The data from their medical records were analyzed descriptively, and survival probabilities were calculated using the Kaplan-Meier method and the logrank test, considering patient, tumor and treatment-related characteristics.
The 82 patients with neuroendocrine tumors of an unknown primary site (34 males) had a median age of 60 years; 57 (69.5%) had histologically well-differentiated tumors, 3 (3.7%) poorly differentiated tumors, and 22 (26.8%) had tumors that could not be classified. Of the 52 patients (62.2%) who underwent Octreoscan® (Bykgulden Italia SpA), 40 (78.4%) showed a pathological uptake and 11 (21.6%) were negative. Thirty-one patients (37.8%) underwent metastatic site surgery, which was radical in 11 cases (35.4%). Forty-eight patients (58.5%) received somatostatin analogues, and 41 (50.0%) underwent chemotherapy. At the end of the study period, 59 patients (72.0%) had died, 31 (53.0%) because of disease progression, and 23 (28.0%) were still alive.
Neuroendocrine tumors of an unknown primary site are difficult to identify but their incidence is higher than previously reported, and the prognosis remains unfavorable.
原发部位不明的神经内分泌肿瘤比其他神经内分泌肿瘤更为罕见（占所有神经内分泌肿瘤的0.6 - 2%），且预后较差。本研究的目的是回顾1984年至2008年期间在米兰国家肿瘤研究所遇到的原发部位不明的神经内分泌肿瘤病例，以核实其发病率，并评估其特征和预后。
在研究期间，750例神经内分泌肿瘤患者到我院就诊，其中82例（10.9%）被诊断为原发部位不明的神经内分泌肿瘤。对其病历数据进行描述性分析，并使用Kaplan-Meier方法和对数秩检验计算生存概率，同时考虑患者、肿瘤及治疗相关特征。
82例原发部位不明的神经内分泌肿瘤患者（34例男性）的中位年龄为60岁；57例（69.5%）为组织学高分化肿瘤，3例（3.7%）为低分化肿瘤，22例（26.8%）肿瘤无法分类。在接受奥曲肽扫描（由拜耳意大利公司生产）的52例患者（62.2%）中，40例（78.4%）显示病理性摄取，11例（21.6%）为阴性。31例患者（37.8%）接受了转移部位手术，其中11例（35.4%）为根治性手术。48例患者（58.5%）接受了生长抑素类似物治疗，41例（50.0%）接受了化疗。在研究期结束时，59例患者（72.0%）死亡，31例（53.0%）死于疾病进展，23例（28.0%）仍然存活。
原发部位不明的神经内分泌肿瘤难以识别，但其发病率高于先前报道，且预后仍然不佳。
