Response to neoadjuvant chemotherapy combined with regional hyperthermia predicts long-term survival for adult patients with retroperitoneal and visceral high-risk soft tissue sarcomas

Abstract

Purpose: To determine the efficacy of neoadjuvant chemotherapy combined with regional hyperthermia (RHT) for local tumor control and overall survival (OS) in adult patients with retroperitoneal or visceral (RP/V) high-risk soft tissue sarcomas (HR-STS).

Patients and methods: From 1991 to 1997, 58 patients with HR-STS at RP/V sites were prospectively treated with four cycles of etoposide, ifosfamide, and doxorubicin combined with RHT followed by surgery, adjuvant chemotherapy, and radiation.

Results: Objective response rate assessable in 40 patients was 13% (five partial responses). Including minor responses (n = 8), the radiographic response rate was 33%. The pathologic response rate assessable in 26 patients after surgical resection was 42%. Median OS was 31 months. At a median observation time of 74 months, 5-year probability of local failure-free survival (LFFS), distant metastasis-free survival, event-free survival, and OS were 25%, 51%, 20%, and 32%, respectively. Averaged minimum temperatures (T(min)) and time-averaged temperatures achieved in 50% (T(50)) and 90% (T(90)) of all measured tumor sites differed significantly between responders and nonresponders (T(min), 39.3 degrees C v 38.0 degrees C; P =.002; T(50), 40.9 degrees C v 40.3 degrees C; P =.038; T(90), 40.1 degrees C v 39.3 degrees C; P =.017). At 5-year follow-up, probability of LFFS (59% v 0%; P <.001) and OS (60% v 10%; P <.001) was significantly in favor of patients responding to neoadjuvant thermochemotherapy.

Conclusion: Response to neoadjuvant chemotherapy combined with RHT is predictive for an improved local tumor control resulting in a long-term survival benefit for patients with HR-STS at unfavorable RP/V sites; however, the impact of RHT has to be defined in a randomized phase III trial.