Clinical analysis of pediatric Langerhans cell histiocytosis involving the thyroid gland in 8 cases / 中华实用儿科临床杂志

ABSTRACT

Objective To explore the clinical features of Langerhans cell histiocytosis (LCH) involving the thyroid gland in children,in order to improve the diagnosis and treatment.Methods The clinical and imaging manifestations,thyroid function,treatment and prognosis of hospitalized children with LCH involving the thyroid gland in Beijing Children's Hospital,Capital Medical University,from July 2007 to July 2016 were analyzed retrospectively.Results In total 556 cases with LCH were analyzed,among which 8 cases (1.44％) were with LCH involving the thyroid gland.The onset age of children with LCH involving the thyroid gland was significantly older than the others with significant difference (average onset age7.6 vs.3.4 year old;t =2.748,P =0.006),while the sex distribution showed no significant difference (1.67 ∶ 1.00 vs.1.38 ∶ 1.00;x2 =0.064,P =0.799).All 8 cases were Group Ⅰ,complicated by multiple organ involvement with vital organs included.None of the 8 cases had significant clinical symptoms of hypothyroidism,and thyroid imaging abnormalities were found in all 8 cases,including goiters and low echoes with irregular shapes,while 5 cases had subclinical hypothyroidism.All 8 cases were given the first-line standard chemotherapy for LCH-Group Ⅰ.Three cases without subclinical hypothyroidism showed good treatment effects and were assessed as non-active state and had already quitted medication.Five cases complicated by subclinical hypothyroidism had unsatisfactory treatment effects,among which 1 case abandoned treatment and 4 cases were adjusted for the second-line standard chemotherapy (Prednisone + Vincristine + Cytarabine + Cladribine).Finally,1 out of 4 case was assessed as non-active state after 3 months of medicine withdrawal,the other 3 cases were still in maintenance therapy.Conclusions LCH involving the thyroid gland is extremely rare,with significantly older onset age,and easily complicated by multiple organ involvement with vital organs included.Patients have no significant clinical symptoms of hypothyroidism,while some have subclinical hypothyroidism.The major imaging changes are goiters and low echoes with irregular shapes.Those LCH involving the thyroid gland complicated by subclinical hypothyroidism turn out to have poor prognosis,but Cladribine and Cytarabine are possible to improve the prognosis of such patients.