Oral squamous cell carcinoma of the tongue that developed 25 years after hematopoietic stem cell transplantation: a case report

Abstract Background The risk of secondary malignancy is significantly higher in patients with chronic graft-versus-host disease (cGVHD) than in those without the condition. cGVHD is one of the most common complications following hematopoietic stem cell transplantation (HSCT). Oral squamous cell carcinoma (OSCC) is a recognized late complication, but most reported cases occur within the first decade after HSCT. We present a rare case of OSCC that developed 25 years after HSCT. Case presentation We report a case of OSCC that developed in a 40-year-old woman 25 years after HSCT. The patient had a history of oral cGVHD following transplantation. The patient presented with an indurated mass measuring approximately 25 × 20 mm on the right lateral tongue. Histopathological examination confirmed squamous cell carcinoma. The patient underwent partial glossectomy with functional neck dissection, followed by reconstruction with a pectoralis major flap. Two months later, cervical lymph node metastasis was detected and managed with additional neck dissection, adjuvant radiotherapy (66 Gy), and chemotherapy. She completed all treatments without interruption and has remained disease-free for 41 months, with preserved speech and swallowing functions. Conclusions This case suggests that the risk of OSCC may persist for decades after HSCT, particularly in patients with a history of cGVHD. The exceptionally long latency emphasizes the need for lifelong oral surveillance in HSCT survivors and the importance of multidisciplinary collaboration between hematologists and head and neck surgeons for early detection and management.