Factors associated with postoperative hypocalcemia following surgery for
thyroid cancer in childhood
Abstract
Background: Postoperative hypocalcemia is a frequent complication after
thyroid surgery. Hypoparathyroidism may develop as transient (TtHP),
with normalization within six months from surgery, or permanent (PtHP)
if the patient requires replacement therapy. The present study analyzes
rates and factors associated with the development of TtHP or PtHP
following thyroid surgery in a pediatric population. Procedure: A
retrospective multicenter study analyzing 363 patients was carried out.
We recorded gender, age, tumor size, type of surgery, lymph node
dissection, histology. Calcium levels were acquired daily for 72 hours
after discharge. Subsequent sample collection was customized on the
patient’s hypocalcemia severity. Results: We analyzed 363 patients aged
≤18 years (mean age 14.2 years) who underwent thyroid surgery clustered
into age groups (≤15 or >15). Patients mean follow-up was
5.8 years (1-11yrs). At histology 310 (85%) were papillary carcinoma,
32 (9%) were follicular carcinoma, 6 (2%) presented diffuse sclerosing
variant of papillary thyroid carcinoma whilst 15 (4%) had familial
medullary carcinoma. TtHP developed in 36 (9,9%), PtHP in 20 (5.5%)
cases. TtHP was more frequent in younger patients (p=0,009). Both PtHP
and TtHP were increased in case of larger tumors (≥2 cm) (p=0,001). All
TtHP and PtHP were in TT group. PtHP rate was increased if lymph node
dissection was carried out (p<0.001). Conclusions: The risk of
hypoparathyroidism is related to younger age, tumor size, TT and lymph
node dissection therefore surgeons should tailor surgery as much as
possible to avert such complication.