Unilateral conjunctival infiltration of Adult T-cell leukemia/lymphoma. Case report and literature review.

Adult T-cell leukemia/lymphoma (ATLL) is a peripheral T-cell lymphoma caused by human T-cell leukemia virus type 1 infection. Although conjunctival lymphoma is commonly reported with B-cell lymphoma, it rarely occurs in cases of ATLL. A 73-year-old Japanese female patient was admitted to our institution with evidence of abnormal lymphocytes, lymphadenopathy, and lung nodular lesions. Acute type ATLL was diagnosed, and therapy following the mLSG15 protocol was initiated. At the end of the second course, new bone lesions were detected. A modified treatment regimen was scheduled, but was postponed due to the appearance of gastrointestinal symptoms. Close observation resulted in a diagnosis of cytomegalovirus enteritis. One month after the diagnosis, the patient developed pain and discomfort in her left eye, which was determined to be due to a bulbar conjunctival tumor. Pathological findings revealed conjunctival infiltration of ATLL. Mogamulizumab treatment was initiated and was successful in eradicating the conjunctival lesions after the first course. However, at the end of the third course of therapy, pancytopenia was noted. Therefore, mogamulizumab therapy was discontinued, and the patient was on follow-up observation. Although there was no relapse of the conjunctival lesions, the patient died 1 year after the initial diagnosis, following therapy resistance.