Myeloid Neoplasia and Lymphoblastic Lymphoma with Eosinophilia After Radioactive Iodine: A Case Report

BACKGROUND

Thyroid cancer is the most common endocrine cancer, with an increasing incidence around the world in the last three decades. The increased risk of secondary cancer is associated with a genetic predisposition or radioactive iodine used in the treatment.

CASE REPORT

A 65-year old male patient was operated on for thyroid papillary cancer. He received radioactive iodine on two occasions postoperatively. After six years, he presented with malaise and fatigue with leukocytosis and eosinophlilia. The physical examination revealed inguinal lymphadenopathies and splenomegaly, after examining the bone marrow and lymph node biopsies, he was diagnosed with eosinophilic myeloproliferative neoplasia and T-cell lymphoblastic leukaemia/lymphoma.

CONCLUSION

Leukaemia and other haematological malignencies may develop after radioactive iodine treatment. Patients with radioactive iodine ablation history should be monitored for a long time.

Secondary acute lymphoblastic leukaemia is constitutional and probably not related to prior therapy

Very little is known about secondary acute lymphoblastic leukaemia (s-ALL). This retrospective analysis studied a cohort of s-ALL patients treated at a single centre between 1994 and 2013, while comparing therapy-associated ALL (t-ALL) and antecedent malignancy ALL (am-ALL) patients. Thirty-two patients with s-ALL were identified. The overall incidence was 9.4% among ALL adults while T-cell s-ALL was rare (12% of s-ALLs). The median time interval between two malignant diagnoses was 5.3 years (range: 0.1-28). In contrast to previous reports, most of the s-ALLs were CD10 + and without KMT2A (MLL) abnormalities. The overall survival (OS) rates of the entire cohort at 12 and 24 months from ALL diagnosis was 49% and 25%, respectively. Most patients (n = 23, 72%) received prior chemo-/radio-therapy for their first malignancy (t-ALL) and only 9 (28%) did not (am-ALL). No significant difference was found in the incidence of B-/T- lineage ALL, extramedullary disease, blood count, and the rate of Philadelphia-positive ALL, nor in the rates of complete remission (P = 0.55) and OS (P = 0.97). This similarity, together with high incidence of family malignancy in both groups, raise the possibility that s-ALL patients may have an inherent predisposition to malignancies and a history of previous therapy may be of lesser importance in the pathogenesis of s-ALL.