Radiation therapy dose is associated with improved survival for unresected anaplastic thyroid carcinoma: Outcomes from the National Cancer Data Base

Abstract

Background We assessed the outcomes of patients with unresected anaplastic thyroid carcinoma (ATC) in the National Cancer Data Base (NCDB) and explored potential relationships between radiation therapy (RT) dose and overall survival (OS). Methods The study group was composed of patients who received either no surgery or grossly incomplete resection. Correlates of OS were explored using univariate and multivariable analysis (MVA) analyses. Results A total of 1,288 patients were analyzed. Mean age was 70.2 years; 59.7% were female; and 47.6% received neck RT. Median OS was 2.27 months, with 11% alive at one year. A positive RT dose-survival relationship was seen for the entire study cohort, for those who received systemic therapy, and for those with stage IVA/IVB and IVC disease. On MVA, older age (HR: 1.317, CI: 1.137–1.526), ≥1 comorbidity (HR: 1.587, CI: 1.379–1.827), distant metastasis (HR: 1.385, CI: 1.216 –1.578), receipt of systemic therapy (HR: 0.637, CI: 0.547–0.742), and receipt of RT as compared with no RT (HR <45 Gy: 0.843, CI: 0.718–0.988; HR 45-59.9 Gy: 0.596, CI: 0.479–0.743; HR 60-75 Gy: 0.419, CI: 0.339 – 0.517) correlated with OS. The RT dose-survival relationship for those who received higher (60-75 Gy) vs. lower (45-59.9 Gy) therapeutic dose was confirmed by propensity score matching. Conclusions Survival was poor in this cohort of patients with unresected ATC and more effective therapies are needed. However, the association of RT dose with OS highlights the importance of identifying patients with unresected ATC who may still yet benefit from multi-modal local-regional treatment incorporating higher dose RT.

Survival advantage of chemoradiotherapy in anaplastic thyroid carcinoma: Propensity score matched analysis with multiple subgroups

“…Median OS was 5.9 vs 9.9 months (surgery + RT with or without chemotherapy) for stage IVB disease; here, we reported median OS of 4.7 vs 7.9 months for the subgroups receiving definitive surgery + RT +/− chemotherapy. Finally, Pezzi et al evaluated the impact of radiotherapy dose in a primarily unresected ATC population . Higher radiotherapy dose was significantly linked to longer OS in a multivariable model; and also demonstrated in PSM‐cohorts comparing 45‐59 Gy vs 60‐75 Gy.…”

Hypofractionated Radiotherapy for Anaplastic Thyroid Carcinoma: 15 Years of Experience in a Single Institution

“…4 Gy was an independent predictor for OS in 3,552 patients. Pezzi et al [11] similarly compared three total dose groups, < 45 Gy, 45-59.9 Gy, and 60-75 Gy, in patients with unresected ATC, and reported that a total dose of 60-75 Gy was an independent predictor for OS in 2,987 patients. Based on the results of those studies and ours, a higher dose of radiation is important for the OS of ATC patients.…”

“…The median OS in their study was 9.3 months. Glaser et al [10] and Pezzi et al [11] reported that radiotherapy with a high total dose improved the OS of ATC patients.…”

Anaplastic thyroid carcinoma: review of treatment protocols

“…However, it is not certain, as to which cumulative doses and whether radiotherapy vs combined radiochemotherapy before or after surgery is beneficial. A recent large analysis of 1288 patients from the NCDB including patients with non-resected ATC survival was significantly better in patients with radiotherapy with a cumulative dose of >45 Gy compared to no radiotherapy or less than 45 Gy (Pezzi et al 2017).…”