The question could be asked: Why use total thyroidectomy at all?

Patients with differentiated thyroid cancer (DTC) at low-to-intermediate risk of recurrence had better health-related quality of life (HRQOL) scores following thyroid lobectomy (TL) than those who underwent total thyroidectomy (TT), at least during the first three postoperative months, the first longitudinal study of its kind has shown.

However, six to 12 months after undergoing either TL or TT, most of the differences in HRQOL between the two groups were no longer apparent, the same research indicated.

In a group of 1,060 patients with DTC, the TT group experienced more postoperative HRQOL problems at one and three months postoperatively compared to the TL group, Wanna Chen, MD, Sun Yat-sen University, Guangzhou, china and colleagues reported in JAMA Surgery.

That said, nearly all the between-group HRQOL differences disappeared six and 12 months later, with the exception of ongoing sleep disturbances following TT, the authors noted.

“Differentiated thyroid cancer… is characterized by a good prognosis, with 10-year overall survival of 92% and disease-specific survival of 99%… [and g]iven the similarly excellent prognosis in patients with DTC who undergo TT and TL, HRQOL has taken on greater importance,” Chen and colleagues observed.

“The findings of this study suggest the HRQOL of patients with DTC with low to intermediate risk of recurrence, including those with tumor size 1 to 4 cm, is not associated with the extent of surgery [but i]f better HRQOL is needed in the short term postoperatively, TL may be preferred,” they wrote.

Patients diagnosed with DTC at low to intermediate risk of recurrence between October 2018 and September 2019 were enrolled in the study.

The overall median age was 38 years (Interquartile range [IQR], 31-47 years), approximately 78% were female, and slightly over half of all patients underwent TL; the remaining patients underwent TT.

Compared to patients in the TL group, TT patients were more likely to have a large tumor in excess of 4 cm (P<0.001); undergo lymph node dissection (P<0.001); and receive radioactive iodine therapy (P<0.001), the investigators pointed out.

“All patients with possible thyroid cancer completed preoperative surveys and were categorized into the TT or TL group according to the surgery they underwent,” the investigators wrote. Patients then were asked to complete an online version of the questionnaires at one, two, six, and 12 months following the procedure.

At one month, 81.4% of patients returned a completed questionnaire; at two months, 74.7% of patients did so; at 6 months, more patients at 85.1% returned a completed questionnaire, but by 12 months, fewer patents at 73.9% returned a completed questionnaire. The nonresponse rates between the two treatment groups were very small and not clinically meaningful.

Using three HRQOL-related questionnaires, researchers found that one month following surgery, patients who had undergone TT reported more anxiety, depression, fatigue, pain, voice change, chills, and tingling than those who had undergone TL. TT patients also reported more neuromuscular, psychological, and sexual symptoms as well as decreased physical, emotional, and social function than TL patients, the researchers added.

Three months postoperatively, the TT group still reported more anxiety, fatigue, appetite loss, as well as neuromuscular, voice changes, and tingling symptoms along with more physical, role, and social dysfunction than the TL group.

“The TT group also had a lower global HRQOL score than the TL group,” the investigators noted, and added that “None of the differences [between the two groups] were statistically significant at six months postoperatively.”

This also held true at one year, with the exception of sleep disturbances, which were more prevalent in the TT group (P=0.02).

After adjusting for tumor size, lymph node dissection and radioactive iodine treatment, “intergroup comparison of HRQOL showed similar results to those without adjustment,” the authors noted.

Some 429 patients had a tumor size of between 1 and 4 cm; among this subgroup of very low-risk patients, some 60% underwent TT and the remainder underwent TL.

Again at one and three months postoperatively, “patients undergoing TT reported significantly poorer HRQOL scores than those undergoing TL,” the study authors reported.

For example, median postoperative scores of anxiety at one month were 3 (IQR, 1-6) in the TT group versus 2 (IQR, 0-4 P=0.007) in the TL group.

At three months, median anxiety scores in both groups were exactly the same as they were one month following surgery.

Again, variations in these two HRQOL measures had disappeared six and 12 months later.

As for postoperative complications, transient hypoparathyroidism within three months of surgery were more prevalent in the TT group at 32.2% compared to 6.2% in the TL group (P<0.001), as was hoarseness at 30.8% versus 21.1%, respectively, (P=0.002).

The authors suggested that at least some of the symptoms reported by TT patients may have been associated with the higher incidence of complications in that group, including transient hypoparathyroidism and hoarseness.

“Another reason may be related to the fluctuation of serum thyrotropin levels after thyroidectomy,” they suggested.

It has been reported elsewhere that thyroxine deficiency may be related to emotional disorders and in the study, the severity of anxiety, depression and psychological problems was associated with the thyrotropin levels and more patients in the TL group had satisfactory thyrotropin levels than those in the TT group: thus, fluctuation of thyrotropin levels may have been partially responsible for the differences in psychological well-being between the two groups, the authors suggested.

In 2015, the American Thyroid Association revised their guidelines and recommended TL as an initial management option for low-to intermediate-risk DTC tumors measuring 1 to 4 cm, given that there is no prognostic advantage for TT over TL in DTC tumors measuring 1 to 4 cm.

Commenting on the findings, Susan Pitt, MD, MPHS, University of Michigan, Ann Arbor, Michigan, pointed out that the strengths of the study include the sample size, the prospective study design, and the use of validated measures to assess HRQOL.

“However, the results are limited by a high rate of nonresponse (15%-26%) [to the questionnaires], the single-institution design, a low proportion of participants older than 55 years, and the possibility of cultural differences affecting generalizability,” Pitt cautioned.

She also noted that asthenia has been shown to be worse following TT, although asthenia was not measured in the current study.

Nevertheless, the fact that the study authors showed that TT patients were more prone to sleep disturbances even one year later and the fact that they had more fluctuating thyrotropin level may contribute to asthenia, the editorialist suggested.

“The findings presented here beg the question raised by the authors concluding sentence: if total thyroidectomy provides equivalent oncologic outcomes but is associated with a higher risk of complications and decreased QoL in the short term, should we be offering this procedure [at all]?” Pitt asked.

  1. Short-term health-related quality of life was better after patients underwent thyroid lobectomy (TL) than after total thyroidectomy (TT) in patients with a low-to-intermediate risk of recurrence.

  2. Six to 12 months after undergoing either TL or TT, most of the differences in HRQOL between the two groups were no longer apparent.

Pam Harrison, Contributing Writer, BreakingMED™

The authors had no conflicts of interest to declare.

Pitt had no conflicts of interest to declare.

Cat ID: 120

Topic ID: 78,120,730,120,192,925,159