Bone Marrow Function After (131)I Therapy in Patients With Differentiated Thyroid Carcinoma.
OBJECTIVE
The primary objective was to evaluate the short- and long-term toxic effects of radioiodine ((131)I) therapy on bone marrow function in differentiated thyroid carcinoma (DTC) patients. The secondary objective was to define characteristics of patients at risk for impaired bone marrow function after (131)I treatment.


METHODS
DTC patients treated with (131)I between 1989 and 2013 were included. We excluded patients with morbidities or treatments that could have influenced blood count parameters. Baseline platelets, leukocytes, and hemoglobin levels were compared with blood counts at 3 and 6 months and at 1 and 5 years after treatment. Logistic multivariate regression analyses were performed to determine patient characteristics associated with thrombocytopenia.


RESULTS
We included 331 patients. Mean ± SD age was 47.5 ± 17.2 years, and 74.0% were female. Posttreatment platelets were significantly decreased at 6 months and 1 year, as compared with baseline. Leukocyte counts were also decreased at 3 and 6 months and at 1 year after treatment. No decreases in hemoglobin were found. Five years after treatment, platelet and leukocyte counts were comparable with baseline. Fourteen patients (4.2%) developed transient posttreatment thrombocytopenia. Risk factors for thrombocytopenia were older age, T4 tumor stage, male gender, and cumulative dose (131)I. After a multivariate regression analysis, the cumulative dose (131)I remained independently associated with thrombocytopenia.


CONCLUSIONS
Posttreatment platelets and leukocytes were transiently decreased compared with pretreatment values in a general DTC population. Cumulative (131)I dose was independently associated with thrombocytopenia. Platelets and leukocytes normalized to baseline levels 5 years after treatment, implying that in most patients the clinical effects of bone marrow toxicity are limited.
Departments of Endocrinology (H.T.P., E.N.K.H., W.J.S., A.N.A.v.d.H.-S., T.P.L.), Nuclear Medicine and Molecular Imaging (A.H.B.), Surgical Oncology (J.T.M.P.), and Hematology (G.W.v.I.), University of Groningen, University Medical Center Groningen, 9700 RB Groningen, The Netherlands.
Hester T
HT
Prinsen
Departments of Endocrinology (H.T.P., E.N.K.H., W.J.S., A.N.A.v.d.H.-S., T.P.L.), Nuclear Medicine and Molecular Imaging (A.H.B.), Surgical Oncology (J.T.M.P.), and Hematology (G.W.v.I.), University of Groningen, University Medical Center Groningen, 9700 RB Groningen, The Netherlands.
Esther N
EN
Klein Hesselink
Departments of Endocrinology (H.T.P., E.N.K.H., W.J.S., A.N.A.v.d.H.-S., T.P.L.), Nuclear Medicine and Molecular Imaging (A.H.B.), Surgical Oncology (J.T.M.P.), and Hematology (G.W.v.I.), University of Groningen, University Medical Center Groningen, 9700 RB Groningen, The Netherlands.
Adrienne H
AH
Brouwers
Departments of Endocrinology (H.T.P., E.N.K.H., W.J.S., A.N.A.v.d.H.-S., T.P.L.), Nuclear Medicine and Molecular Imaging (A.H.B.), Surgical Oncology (J.T.M.P.), and Hematology (G.W.v.I.), University of Groningen, University Medical Center Groningen, 9700 RB Groningen, The Netherlands.
John T M
JT
Plukker
Departments of Endocrinology (H.T.P., E.N.K.H., W.J.S., A.N.A.v.d.H.-S., T.P.L.), Nuclear Medicine and Molecular Imaging (A.H.B.), Surgical Oncology (J.T.M.P.), and Hematology (G.W.v.I.), University of Groningen, University Medical Center Groningen, 9700 RB Groningen, The Netherlands.
Wim J
WJ
Sluiter
Departments of Endocrinology (H.T.P., E.N.K.H., W.J.S., A.N.A.v.d.H.-S., T.P.L.), Nuclear Medicine and Molecular Imaging (A.H.B.), Surgical Oncology (J.T.M.P.), and Hematology (G.W.v.I.), University of Groningen, University Medical Center Groningen, 9700 RB Groningen, The Netherlands.
Anouk N A
AN
van der Horst-Schrivers
Departments of Endocrinology (H.T.P., E.N.K.H., W.J.S., A.N.A.v.d.H.-S., T.P.L.), Nuclear Medicine and Molecular Imaging (A.H.B.), Surgical Oncology (J.T.M.P.), and Hematology (G.W.v.I.), University of Groningen, University Medical Center Groningen, 9700 RB Groningen, The Netherlands.
Gustaaf W
GW
van Imhoff
Departments of Endocrinology (H.T.P., E.N.K.H., W.J.S., A.N.A.v.d.H.-S., T.P.L.), Nuclear Medicine and Molecular Imaging (A.H.B.), Surgical Oncology (J.T.M.P.), and Hematology (G.W.v.I.), University of Groningen, University Medical Center Groningen, 9700 RB Groningen, The Netherlands.
Thera P
TP
Links
D000230:Adenocarcinoma / Q000503:physiopathology / Q000532:radiotherapy*; D000328:Adult; D000368:Aged; D001853:Bone Marrow / Q000473:pathology* / Q000503:physiopathology; D005260:Female; D006801:Humans; D007457:Iodine Radioisotopes / Q000627:therapeutic use; D007958:Leukocyte Count; D008297:Male; D008875:Middle Aged; D011879:Radiotherapy Dosage; D013964:Thyroid Neoplasms / Q000473:pathology / Q000503:physiopathology / Q000532:radiotherapy*; D016896:Treatment Outcome
D007457:Iodine Radioisotopes