Previous Cancer Not Seen to Raise Thyroid Surgery Risks for Children
Children successfully treated for a cancer who undergo thyroid surgery for a secondary thyroid disease have a similar risk of surgical complications, such as permanent hypoparathyroidism, as children without a previous cancer, a single-center study in the U.S. shows.
These findings add to an ongoing discussion of whether cancer survivors, who have a higher risk of thyroid nodules and cancer, should be routinely screened for thyroid disease due to thyroid surgery risks potentially outweighing benefits if a nodule is found.
Notably, complication rates were very low for both groups, which the researchers believe was associated with these procedures being conducted by high-volume, pediatric surgery specialists, as previously reported. As such, this study further supports such risks not being greater for cancer survivors when thyroid surgery is performed by high-volume surgeons.
The study, “Surgical outcomes in survivors of childhood cancer undergoing thyroidectomy: A single-institution experience,” was published in the Journal of Pediatric Surgery.
Thyroidectomy, a surgery to remove all or part of the thyroid gland, can lead to a number of complications, including the unintentional damage or removal of the neighboring parathyroid glands, which produce the parathyroid hormone (PTH) that regulates calcium and phosphate levels in the blood.
Parathyroid glands’ damage or removal can lead to the production of low or no PTH levels, a condition called hypoparathyroidism. This post-surgical complication can be temporary or permanent, in which case patients need life-long monitoring and treatment.
“Given the increased prevalence of thyroid cancer in the pediatric population, children with thyroid nodules are increasingly referred for definitive treatment with thyroid surgery,” the researchers wrote.
Previous studies reported higher rates of thyroid surgery complications in children relative to adults, but recent research suggest that comparable outcomes can be achieved when performed by high-volume surgeons.
Childhood cancer survivors (CCS) are at increased risk for thyroid disease, including nodules and cancer, due to exposure to cancer treatment, particularly head and neck radiation therapy.
“CCS undergoing surgery for secondary thyroid disease represent a potentially higher risk subset of patients, given their increased likelihood of exposure to radiation, as well as the presence of other chronic [simultaneous health conditions],” the researchers wrote.
However, there is limited evidence on their post-surgical outcomes after thyroid surgery.
A team of researchers at the Children’s Hospital of Philadelphia (CHOP) analyzed the medical records of 638 children undergoing thyroidectomy at CHOP’s pediatric thyroid center between 2009 and 2020. They compared post-surgical outcomes between children with and without a history of primary childhood cancer.
In total, 42 children (6.6%) had such a history, with the primary cancer diagnosed at a median age of 4 (range, 0–16 years). Most (86%) received radiation therapy with potential thyroid exposure.
Among the other 596 children without a prior childhood cancer, 236 had sporadic/familial thyroid cancer, 179 had Graves’ disease, and 181 had other benign thyroid conditions.
Compared with these non-CCS groups, children with a prior cancer were significantly older at the time of thyroid surgery (median age of 17 vs. 15 years) and a significantly lower proportion were girls (54.8% vs. 81.8–82.7%).
Total thyroidectomy was performed in all Graves’ patients, in a vast majority of CSS (85.7%) and children with thyroid cancer (75.9%), and in about one-third (32%) of those with benign thyroid conditions.
Notably, no significant differences in surgical complication rates were seen between CCS and children with sporadic/familial thyroid cancer or Graves’ disease, regardless of type of thyroidectomy.
However, temporary hypoparathyroidism was significantly more common among CCS patients found to have benign nodules post-surgery relative to those with benign thyroid conditions (70.6% vs. 25.4%). This was likely due to a significantly greater proportion of total thyroidectomy in the CCS group, the team noted.
Nevertheless, long-term surgical complications rates, such as permanent hypoparathyroidism and recurrent laryngeal nerve (RLN) paralysis, were comparable between CCS and all non-CCS groups. RLN paralysis refers to injury to a nerve of the voice box.
Notably, permanent hypoparathyroidism was reported in only 15 children (2.4%).
In addition, when adjusted for age and stratified by type of surgery, the risk of surgical complications was similar among groups.
These findings highlight that children previously treated for cancer “are not at higher risk of long-term complications from thyroid surgery when treated by high-volume surgeons within a multidisciplinary team,” confirming “improved outcomes among children undergoing thyroid surgery when treated at multidisciplinary high-volume centers,” the researchers wrote.
“This is of particular importance for a population such as CCS who may have increased risks for complications due to their prior cancer treatment,” they added.
Study findings also add “further data to the ongoing discussion on guidelines for thyroid cancer screening among CCS,” suggesting that the benefits of such screening and subsequent thyroid surgery if a nodule is found may outweigh its risks if performed by high-volume surgeons, the team wrote.