Silverman J F, Baird D B, Teot L A, Cappellari J O, Geisinger K R
Department of Pathology and Laboratory Medicine, East Carolina University School of Medicine, Greenville, NC 27858-4354, USA.
Diagn Cytopathol. 1996 Jul;15(1):54-9. doi: 10.1002/(SICI)1097-0339(199607)15:1<54::AID-DC11>3.0.CO;2-B.
Small cell carcinoma of the large intestine is a rare, extremely aggressive malignancy often associated with an overlying adenoma. We report three cases of metastatic small cell carcinoma of the colon diagnosed by fine-needle aspiration (FNA) biopsy. Two of the patients were women (ages 33 and 46 yr old) and one was a man (69 yr old). FNA biopsy established the diagnosis of metastatic small cell carcinoma involving the liver (2 cases) and soft tissue of the scapular region (1 case). In one patient, the FNA diagnosis of hepatic metastases preceded identification of the primary site. Subsequently, the patient was found to have a small cell carcinoma subadjacent to a colonic villous adenoma, illustrating the importance of investigating villous lesions of the colon in patients with metastatic small cell carcinoma of unknown primary origin (especially in non-smokers). All three cases showed the characteristic cytologic features of small cell carcinoma. Ancillary studies performed on aspirated material confirmed the diagnosis of small cell carcinoma in one case. Immunocytochemical studies revealed punctate cytokeratin and diffuse neuron-specific enolase (NSE) positivity of the malignant cells. Ultrastructurally neurosecretory granules were evident. To the best of our knowledge, this is the first FNA cytologic report of metastatic small cell carcinoma of the large intestine. This FNA report also demonstrates when a small cell carcinoma is detected in a metastatic site in a patient lacking a lung primary, a likely primary site could be adjacent or beneath a polypoid lesion of the colon.
大肠小细胞癌是一种罕见的、极具侵袭性的恶性肿瘤，常与覆盖其上的腺瘤相关。我们报告3例经细针穿刺抽吸活检（FNA）诊断的结肠转移性小细胞癌。其中2例患者为女性（年龄分别为33岁和46岁），1例为男性（69岁）。FNA活检确诊为转移性小细胞癌，累及肝脏（2例）和肩胛区软组织（1例）。在1例患者中，FNA诊断肝转移先于原发部位的确定。随后，该患者被发现结肠绒毛状腺瘤下方存在小细胞癌，这表明对于不明原发灶的转移性小细胞癌患者（尤其是非吸烟者），调查结肠绒毛状病变具有重要意义。所有3例均表现出小细胞癌的特征性细胞学特征。对抽吸物进行的辅助检查在1例中证实了小细胞癌的诊断。免疫细胞化学研究显示恶性细胞点状细胞角蛋白和弥漫性神经元特异性烯醇化酶（NSE）阳性。超微结构显示神经分泌颗粒明显。据我们所知，这是第一例关于大肠转移性小细胞癌的FNA细胞学报告。该FNA报告还表明，当在无肺原发灶的患者转移部位检测到小细胞癌时，可能的原发部位可能在结肠息肉样病变的附近或下方。
