Interdigitating dendritic cell sarcoma (IDCS) is an extremely rare subtype of dendritic cell neoplasms, and current knowledge on this tumor is limited. We herein report a case of an IDCS in a 64-year-old man who presented with a right inguinal mass combined with extensive retroperitoneal, pulmonary, hepatic, renal, and bone marrow infiltration. Because of the advanced stage of the disease, we performed five cycles of chemotherapy, including cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP); doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD); and ABVD combined with cisplatin, and one cycle of radiotherapy. The patient\'s inguinal mass became smaller during the treatment, but there was no change in the extent of infiltration at the other sites. The patient died 8 months after the initial diagnosis. We also herein review the etiology, diagnosis, differential diagnosis, treatment, and prognosis of IDCS, and analyze the characteristics of IDCS in Chinese patients.

BACKGROUND: Angioleiomyoma is an uncommon benign soft tissue tumor and originates from the vascular smooth muscle. It often causes pain and is rarely found in inguinal region. We present a rare case of inguinal canal angioleiomyoma of a female patient who suffered from right groin pain for 4 years and mimicking inguinal hernia clinically.
METHODS: A 53-year-old Chinese female patient presented with 4-year history of right groin pain which was exacerbated by movement. Magnetic resonance imaging was performed in view of atypical presentation and absence of cough impulse. Inguinal canal was subsequently explored by open approach and the mass was found arising from the posterior wall of the inguinal canal and measured 5.2 cm × 3.8 cm. The posterior wall was repaired by Bassini approach after the mass was resected en-bloc. Inguinal pain was resolved and no hernia was found during follow-up. Pathology of the resected specimen confirmed angioleiomyoma with clear resection margins.
CONCLUSIONS: This is the first report of a case of angioleiomyoma of the inguinal canal, which presents as a painful mass. Magnetic resonance imaging should be considered when presenting history and physical examination does not confirm with the diagnosis of inguinal hernia. After inguinal canal exploration, suture or mesh repair should be performed to prevent weakening of posterior wall leading to inguinal hernia.