Isolated testicular recurrence of B cell acute lymphoblastic leukaemia in an adult: rare case.

An 80-year-old man who was previously diagnosed with Philadelphia+ B cell-acute lymphoblastic leukaemia (B-ALL) in remission post-allogeneic matched unrelated donor peripheral blood stem cell transplant. Five years later, he was found to have unilateral testicular relapse of Philadelphia+ B-ALL proven by pathology after radical orchiectomy. Bone marrow aspirate and biopsy did not show evidence of leukaemia. Patient was treated with adjuvant radiation therapy and started on dasatinib 50 mg daily. Given his age and absence of disseminated acutelymphoblastic leukaemia (ALL), no adjuvant chemotherapy was utilised. He is monitored with monthly PCR studies. At 1-year follow-up, no findings suggestive of recurrence of ALL have been identified and the patient is maintained on the dasatinib. Although isolated testicular recurrence is common among paediatric population, it is a rare event among adults as it is considered an immunological sanctuary for cancer cells.