Alan Pollack

PURPOSE: To determine the effect of radiotherapy dose on prostate cancer patient outcome and biopsy positivity in a phase III trial. PATIENTS AND METHODS: A total of 305 stage T1 through T3 patients were randomized to receive 70 Gy or 78 Gy of external-beam radiotherapy between 1993 and 1998. Of these, 301 were assessable; stratification was based on pretreatment prostate-specific antigen level (PSA). Dose was prescribed to the isocenter at 2 Gy per fraction. All patients underwent planning pelvic computed tomography scan to confirm prostate position. Treatment failure was defined as an increasing PSA on three consecutive follow-up visits or the initiation of salvage treatment. Median follow-up was 40 months. RESULTS: One hundred fifty patients were randomized to the 70-Gy arm and 151 to the 78-Gy arm. The difference in freedom from biochemical and/or disease failure (FFF) rates of 69% and 79% for the 70-Gy and 78-Gy groups, respectively, at 5 years was marginally significant (log-rank P = .058). Multiple-covariate Cox proportional hazards regression showed that the study randomization was an independent correlate of FFF, along with pretreatment PSA, Gleason score, and stage. The patients who benefited most from the 8-Gy dose escalation were those with a pretreatment PSA of more than 10 ng/mL; 5-year FFF rates were 48% and 75% (P = .011) for the 70-Gy and 78-Gy arms, respectively. There was no difference between the arms (∼80% 5-year FFF) when the pretreatment PSA was ≤ 10 ng/mL. CONCLUSION: A modest dose increase of 8 Gy using conformal radiotherapy resulted in a substantial improvement in prostate cancer FFF rates for patients with a pretreatment PSA of more than 10 ng/mL. These findings document that local persistence of prostate cancer in intermediate- to high-risk patients is a major problem when doses of 70 Gy or less are used.

BACKGROUND Cystosarcoma phyllodes is a rare sarcoma of the breast. Although surgical removal is the mainstay of treatment, the extent of surgery required (excision vs. mastectomy) and the need for additional local therapy, such as radiotherapy, are unclear. The current study evaluated the rate of local and distant failure, as well as potential prognostic factors, to better define appropriate treatment strategies. METHODS One hundred one patients treated primarily for cystosarcoma phyllodes of the breast were evaluated. These tumors were classified histologically into benign (58%), indeterminate (12%), and malignant (30%) based on well defined criteria. Stromal overgrowth (29%) was considered separately. Surgery was comprised of local excision with breast conservation (47%) or mastectomy (53%). Microscopic surgical margins were negative in 99% of cases. Six patients received adjuvant radiotherapy. RESULTS Overall survival for the 101 patients was 88%, 79%, and 62% at 5, 10, and 15 years, respectively. For patients with nonmalignant (benign or indeterminate) and malignant cystosarcoma phyllodes, the overall survival was 91% and 82%, respectively, at 5 years, and 79% and 42%, respectively, at 10 years. Similar rates were observed based on the presence or absence of stromal overgrowth. Local recurrence occurred in 4 patients, with an actuarial 10‐year rate of 8%. Eight patients developed distant metastases, with an actuarial 10‐year rate of 13%. Multivariate analysis using Cox proportional hazards regression revealed stromal overgrowth to be the only independent predictor of distant failure. CONCLUSIONS Local failure in this group of largely margin negative patients with cystosarcoma phyllodes of the breast was low, showing that breast‐conserving surgery with appropriate margins is the preferred primary therapy. The current study data do not support the use of adjuvant radiotherapy for patients with adequately resected disease. Patients with stromal overgrowth, particularly when the tumor size was > 5 cm, were found to have a high rate of distant failure; such patients merit consideration of a trial that examines the efficacy of systemic therapy. Cancer 2000;89:1502–11. © 2000 American Cancer Society.

Our purpose was to examine the role of radiotherapy in the management of phyllodes tumor of the breast. Eight patients were treated with adjuvant radiotherapy for nonmetastatic phyllodes tumor of the breast at the M.D. Anderson Cancer Center between December 1988–August 1993. Tumors were classified as benign (n = 2), borderline (indeterminate; n = 1), or malignant (n = 5). Median follow-up was 36.5 months. Primary surgery consisted of either lumpectomy in 2 patients or mastectomy in 6 patients. Seven patients received adjuvant radiation therapy to the breast or chest wall to a dose of 60 Gy. One patient received 50 Gy to the breast, followed by an interstitial boost of 20 Gy for a total of 70 Gy. Radiotherapy was administered for a combination of reasons, including bulky tumor volume, positive margins, recurrence, and/or malignant histology. There were no local or distant failures. This retrospective review suggests that adjuvant radiotherapy may be underutilized in the treatment of phyllodes tumor of the breast, particularly in patients with adverse features. Although treatment to the breast or chest wall (not the lymphatics) to a dose of 60 Gy appears effective, a dose-response has not been established, and lower doses (50–60 Gy) may be equally effective. Radiat. Oncol. Invest. 6:264–267, 1998.