In an analysis reported in JAMA Oncology, Wang et al found that pathologic complete response (pCR) was associated with improved outcomes among patients with localized soft-tissue sarcoma receiving neoadjuvant chemoradiotherapy or radiotherapy.
The analysis included data from patients from two RTOG single-arm phase II trials in soft-tissue sarcoma: 79 patients from RTOG 0630, which evaluated preoperative radiotherapy alone and 64 from RTOG 9514, which evaluated preoperative chemoradiotherapy.
Key Findings
A total of 123 patients from both studies were evaluable for pCR: 14 (27.5%) of 51 in trial 9514 and 14 (19.4%) of 72 in trial 0630 had pCR.
Five-year overall survival was 100% for patients with pCR vs 76.5% (95% confidence interval [CI] = 62.3%–90.8%) and 56.4% (95% CI = 43.3%–69.5%) for patients with less than pCR in trials 9514 and 0630, respectively. Five-year disease-free survival for patients with pCR vs less than pCR was 88.9% vs 62.7% in trial 9514 and 90.9% vs 40.0% in trial 0630. Local failure rates at 5 years were 0% in patients with pCR vs 11.7% and 9.1% in trials 9514 and 0630, respectively.
On multivariate analysis in patients from both trials , pCR vs less than pCR was associated with improved overall survival (hazard ratio [HR] not estimable due to absence of events in pCR group, P = .01), improved disease-free survival (HR for less than pCR vs pCR = 4.91, 95% CI = 1.51–15.93, P = .008), improved distant disease-free survival (HR = 4.33, 95% CI = 1.32–14.14, P = .02), and reduced risk of distant metastasis (HR = 4.09, 95% CI = 1.25–13.36, P =.02).
On multivariate analysis, histologic types other than leiomyosarcoma, liposarcoma, and myxofibrosarcoma were associated with worse overall survival (HR = 2.24, 95% CI = 1.12–4.45, P = .02).
The investigators concluded: “This ancillary analysis of [two] nonrandomized clinical trials found that pCR was associated with improved survival in patients with [soft-tissue sarcoma] and should be considered as a prognostic factor of clinical outcomes for future studies.”
Dian Wang, MD, PhD, of Rush University Medical Center, is the corresponding author for the JAMA Oncology article.
Disclosure: The study was supported by grants from the National Cancer Institute. For full disclosures of the study authors, visit jamanetwork.com.
