Sasaki Kenichi, Kimura Masaki, Sakamoto Akihiko, Endo Kaori, Kanatani Atsushi, Takahashi Sayuri, Yamada Yukio, Ishida Tsuyoshi, Abe Satoshi, Kawano Hirotaka, Miyazaki Hideyo, Nakagawa Tohru
Department of Urology, Teikyo University School of Medicine.
Department of Pathology, Teikyo University Hospital.
Nihon Hinyokika Gakkai Zasshi. 2020;111(3):102-106. doi: 10.5980/jpnjurol.111.102.
A 39-year-old man was referred to us for further examination of a right inguinal mass. He had noticed the mass several months prior and had undergone positron emission tomography/computed tomography, which revealed a mass with an SUVmax of 1.48 at the right inguinal subcutis. Magnetic resonance imaging (MRI) showed a well-circumscribed, heterogeneously enhanced adipose tumor 7cm in length, adjacent to the right spermatic cord and corpora cavernosa with clear boundaries. The tumor was a suspected atypical lipomatous tumor (well-differentiated liposarcoma), and he underwent tumor extirpation surgery. At surgery, the right inguinal canal was not opened, and the right spermatic cord and corpora cavernosa were safely spared. The excised specimen was composed of lipomatous tissue macroscopically. Histopathological diagnosis was of a spindle cell lipoma. Spindle cell lipomas are relatively rare, benign tumors, comprising only 1.5% of all lipomatous tumors. They arise most commonly in the shoulder and posterior region of the neck, and rarely develop in the groin. Differential diagnosis includes atypical lipomatous tumors, but radiological diagnosis is often difficult because of similar findings on MRI. Spindle cell lipomas typically present as a subcutaneous tumor, while atypical lipomatous tumors arise in the deep layers of connective tissue. This difference in the site of the tumor may contribute to their differential diagnosis before surgery.
一名39岁男性因右侧腹股沟肿物前来我院进一步检查。他数月前发现了该肿物，并接受了正电子发射断层扫描/计算机断层扫描，结果显示右侧腹股沟皮下有一个最大标准化摄取值（SUVmax）为1.48的肿物。磁共振成像（MRI）显示一个边界清晰、长度为7cm的脂肪肿瘤，不均匀强化，毗邻右侧精索和海绵体，边界清晰。该肿瘤疑似非典型脂肪瘤性肿瘤（高分化脂肪肉瘤），他接受了肿瘤切除手术。手术中，未打开右侧腹股沟管，右侧精索和海绵体得以安全保留。切除的标本肉眼可见为脂肪组织。组织病理学诊断为梭形细胞脂肪瘤。梭形细胞脂肪瘤是相对罕见的良性肿瘤，仅占所有脂肪瘤性肿瘤的1.5%。它们最常见于肩部和颈部后部，很少在腹股沟区发生。鉴别诊断包括非典型脂肪瘤性肿瘤，但由于MRI表现相似往往难以做出影像学诊断。梭形细胞脂肪瘤通常表现为皮下肿瘤，而非典型脂肪瘤性肿瘤则发生于结缔组织深层。肿瘤部位的这种差异可能有助于术前进行鉴别诊断。
