Bone Hematopoietic Stem Cell Transplantation (HSCT) following high-dose chemo- and radiotherapy became treatment of choice in various numbers of hematological and hereditary or acquired immune disorders. Protocols preparing to allogenic transplantation have a few aims: eradication of neoplastic disease, suppression of defense system of recipient (reduction of transplant rejection), preparation of bone marrow microenvironment to implantation donor's cells. Chemotherapy is combined with acute side effects as nausea, vomiting, diarrhea, hair loss, mucositis, and hemorrhagic cystitis. Late toxic effects also appear, it require prolonged observation and care. Among them most common is dysfunction of thyroid and gonads in adults and growth inhibition in children. The aim of this study was prospective evaluation of thyroid function in adults with autologous and allogeneic BMT or HSCT following myeloablative chemotherapy.
Material and methods: 23 patients (16 females and 7 males) treated in Department of Hematology and Transplantology Medical University of Gdańsk were included. Average age was 34.3 years with range from 17-50 years. Each patient had endocrinological interview, physical examination of thyroid, TSH level assessment and ultrasonographic thyroid volume measurement before HSCT Identical control examinations were performed in third and twenty month after transplantation. TSH level and thyroid volume were tested for significant differences before and after transplantation using paired t-tests. A P-value of < 0.05 was considered statistically significant.
Results: 12 months after HSCT following myeloablative chemotherapy we noted on average decrease in volume of thyroid from 17,5 ml to 13.5 ml (females to 9.7 ml). This difference was statistically significant with p = 0.002. Also 12 months after the procedure progressive rise in TSH level was noted from 2.0 mU/l to 3.2 mU/l. Nevertheless this tendency was not statistically significant with p = 0.08.
Conclusions: We suggest control of TSH, fT4 level and thyroid ultrasound examination at least twice--before and 12 months after transplantation. Myeloablative chemotherapy before HSCT may cause early (after 3 months) hypothyroidism--it may last one year after procedure. In case of high TSH level we suggest individually adapted L-thyroxine replacement therapy.