Time-Varying Pattern of Mortality and Recurrence from Papillary Thyroid Cancer: Lessons from a Long-Term Follow-Up

Abstract

Background: Little is known about annual hazard rates of cancer mortality and recurrence for papillary thyroid cancer (PTC). This study investigated the time-varying pattern of cancer death and recurrence from PTC and independent prognostic factors for cause-specific mortality (CSM) and recurrence of PTC. Methods: This retrospective chart review enrolled 466 patients diagnosed with PTC who underwent curative initial surgery between April 1981 and December 1991 with a median follow-up of 18.4 years. Clinical characteristics, cancer mortality (primary endpoint), and recurrence (secondary endpoint) were ascertained. The failure rates of either death or recurrence were estimated using the Kaplan-Meier methods, and annual death/recurrence hazard was depicted using hazard function. Results: In this Japanese cohort where only 1.5% of patients received radioactive iodine therapy, the 10-, 20-, and 30-year CSM rates were 2.7%, 6.2%, and 8.6%, respectively. Eleven (44.0%) cases of death occurred within the first 10 years, whereas 10 (40.0%) and 4 (16.0%) cases occurred within 10-20 and 20-30 years after surgery, respectively. The 10-, 20-, and 30-year recurrence rates were 11.3%, 21.8%, and 29.4%, respectively. Forty-six (54.8%) cases of recurrence occurred within the first 10 years, predominantly within the first five years (31 cases; 36.9%), whereas 29 (34.5%), 7 (8.3%), and 2 (2.4%) cases occurred within 10-20, 20-30, and ‡30 years after surgery, respectively. Age ‡55 years was the only independent prognostic factor for CSM. Age ‡55 years, male, tumor size > 4 cm, extranodal extension, and positive pathological lymph node metastasis were independent prognostic factors for recurrence. The annual hazard curve of cancer mortality presented a double-peaked distribution, with a first peak at the 10th year, and the second peak reaching the maximum at the 20th year after surgery for the entire population. The annual hazard curve of recurrence showed a triple-peaked pattern, with surges at about 12, 22, and 29 years after surgery. Conclusions: Patients with PTC harboring at least one of the prognostic characteristics may be at persistent risk of cancer mortality and recurrence even 10 or more years after initial treatment. Understanding the hazard rate of PTC is key to creating more tailored treatment and surveillance.

GADD45B Transcript Is a Prognostic Marker in Papillary Thyroid Carcinoma Patients Treated With Total Thyroidectomy and Radioiodine Therapy

“…In general, PTC is an indolent disease and recurrence can appear long periods after surgery, making the identification of molecular prognostic markers a challenge (34). Herein, we investigated the most common gene alterations described in PTC, as well as transcriptomic data, to identify markers able to anticipate the outcome of patients treated with total thyroidectomy followed by radioiodine therapy.…”

Follow-up of low risk thyroid cancer patients: can we stop follow-up after 5 years of complete remission?

“…One may speculate that, in the wellknown study by Mazzaferri and Jhiang (12), the number of recurrences would have been lower if modern diagnostic modalities had been used to confirm complete remission, and to guide treatment of persistent disease, after initial treatment. Nevertheless, Mazzaferri and Jhiang's key observation that DTC recurrences are not infrequently diagnosed far more than 5 years after initial treatment is confirmed in some recent studies where modern follow-up methods have been already been used (10,93,103). On the other hand, studies that claim that most recurrences are diagnosed within 5 years after treatment have relatively low numbers of patients observed more than 5 or 10 years (106).…”

Prognostic lncRNA, miRNA, and mRNA Signatures in Papillary Thyroid Carcinoma

“…The 30-year cancer-specific death rate from PTC was less than 10% (Grogan et al, 2013). However, the 30-year recurrence rate was close to 30% (Dong et al, 2019).…”