Treatment Option Overview
PORT has been tested in a single-institution randomized trial of 141 patients with extremity sarcomas who were treated with limb-sparing surgery. Patients with high-grade tumors (n = 91) also received adjuvant chemotherapy (i.e., five 28-day cycles of doxorubicin and cyclophosphamide). All patients were randomly assigned to receive radiation (45 Gy to a wide field, plus a tumor-bed boost of 18 Gy over 6–7 weeks), concurrent with chemotherapy in the case of high-grade tumors versus no radiation. At up to 12 years of follow-up, there was one local recurrence in the 70 patients randomly assigned to receive radiation versus 17 recurrences in the 71 control patients (P = .0001), with similar reduction in risk of local recurrence for both high- and low-grade tumors. However, there was no difference in OS between the radiation and control groups.[Level of evidence: 1iiDiii] Global quality of life was similar in the two groups, but the radiation therapy group had substantially worse functional deficits resulting from reduced strength and joint motion as well as increased edema.
To limit acute toxicity with preRX, smaller fields and lower doses are generally given than is the case with PORT. PreRX has been directly compared with PORT for extremity soft tissue sarcomas in a multicenter randomized trial.[13,14,15] Designed to include 266 patients, the trial was stopped early after 190 patients had been accrued because of an increase in wound complications in the preRX group. The scheduled radiation in the preRX group was a wide field of 50 Gy in 2 Gy fractions (first phase of the trial) with an additional 16 Gy to 20 Gy to the tumor bed and a 2-cm margin (second phase of the trial) only if tumor cells were found at the surgical margins.
Patients in the PORT group were scheduled to receive radiation during both phases of the trial. The wound-complication rates were 35% versus 17% in the preRX and PORT groups, respectively (P = .01). In addition, limb function at 6 weeks after surgery was worse in the preRX group (P = .01). At 5 years, the two groups had similar local control rates (93% vs. 92%) and OS (73% vs. 67%, P = .48). Of the 129 patients evaluated for limb function at 21 to 27 months after surgery (n = 73 for preRX and n = 56 for PORT), limb function was similar in both groups, but there was a statistical trend for less fibrosis in the preRX group (P = .07).