Case report: Partial regression of metastatic squamous cell carcinoma with altered azathioprine dosage after long-term use in renal transplant patient.

Introduction: We report the partial regression of metastatic squamous cell carcinoma (SCC) after reduction of long-term azathioprine therapy while awaiting surgery. The patient was a 69-year-old man with a history of kidney transplantation. Moderately differentiated SCC arising in the anterior neck was initially diagnosed, followed later by poorly differentiated SCC metastases to cervical lymph nodes.