Is anastomotic biopsy necessary before radiotherapy after radical prostatectomy?

PURPOSE: External beam radiotherapy may be given after radical prostatectomy as adjuvant (immediate) or therapeutic (delayed) treatment, the latter in response to evidence of disease recurrence. In patients receiving delayed radiotherapy the necessity of a positive anastomotic biopsy before treatment remains unclear. We determined whether a positive anastomotic biopsy predicted the response to radiation in this setting. MATERIALS AND METHODS: We reviewed the records of 67 patients who received radiotherapy for biochemical or biopsy proved recurrent prostate cancer after radical prostatectomy. Patients underwent surgery at our institution or its affiliated hospitals, or were referred to our institution for radiotherapy. All patients had a negative metastatic evaluation before receiving radiotherapy. Biochemical failure after radiotherapy was defined as serum prostate specific antigen (PSA) 0.2 ng./dl. or greater on 2 or more consecutive occasions. Biochemical recurrence-free survival was calculated using the Kaplan-Meier method. Independent predictors of PSA failure after radiotherapy were identified using the multivariate Cox proportional hazards model. RESULTS: Of the 67 patients evaluated 33 and 34 received radiotherapy for biochemical failure and biopsy proved local recurrence, respectively. The 3-year recurrence-free survival rate was 49% in patients treated for biochemical failure and 39% in those with biopsy proved local recurrence. There was no significant difference in PSA-free survival in these 2 groups. Only pre-radiotherapy PSA 1 ng./dl. or greater (p = 0.02) and seminal vesicle invasion (p = 0.02) were significant independent predictors of biochemical failure. CONCLUSIONS: A positive anastomotic biopsy did not predict an improved outcome after radiotherapy following radical prostatectomy. Anastomotic biopsy was associated with a longer time to salvage radiotherapy. However, this delay did not translate into worse disease-free outcomes in patients who underwent anastomotic biopsy. High pre-radiotherapy PSA greater than 1 ng./ml. was the most significant predictor of biochemical failure after therapeutic radiotherapy. Decisions regarding local radiation therapy after radical prostatectomy may be made without documenting recurrent local disease.

Prostate volume change after radioactive seed implantation: possible benefit of improved dose volume histogram with perioperative steroid.

PURPOSE: To evaluate the changes in prostate volume associated with radioactive seed implantation and identify factors that influence prostate swelling. METHODS AND MATERIALS: Between June 1997 and August 1999, 161 patients implanted for prostate carcinoma at the University of California, San Francisco, had prostate volume measurements taken at 4 time points (preplan, preimplant, postimplant, postimplant dosimetry). Patient records were reviewed for treatment with perioperative steroids, hormone therapy (nHT), and external beam radiotherapy (EBRT). One and 2-way analysis of variance (ANOVA) methods were used to test differences in mean effects among patient subsets. RESULTS: A mean 20% volume increase was noted immediately postimplant overall (p < 0.0001), and even with EBRT and/or HT. Steroids were associated with a mean volume decrease of 19.9%, by 3-4 weeks post-procedure (p < 0.0001). Without steroids, only a 3.8% mean change was seen (p = ns). Steroid use resulted in a significant increase in mean dose-volume histogram (DVH) (p = 0.001); however, this benefit was only observed among patients who did not receive steroid. A consistently high DVH occurred with steroid use. CONCLUSION: A significant decrease in prostate volume and improved DVH are associated with steroid use. The diminished benefit of steroid use and higher mean DVH achieved in later years suggests the existence of a significant "learning curve" for brachytherapy procedures.

Management of a positive surgical margin after radical prostatectomy: decision analysis.

PURPOSE: We created and tested a decision analysis model to help determine the preferred management of a positive surgical margin(s) after radical prostatectomy. MATERIALS AND METHODS: We constructed a decision tree modeling surveillance versus immediate prophylactic adjuvant radiation in patients with a positive surgical margin(s) after radical prostatectomy. Literature and institution based estimates were determined for certain factors, including the probability of undetectable prostate specific antigen (PSA) in patients followed expectantly postoperatively and those treated with immediate adjuvant radiotherapy, complications of radiotherapy after prostatectomy and probability of undetectable PSA in those treated with therapeutic radiation for detectable PSA postoperatively. A panel of experts assigned utilities to the various outcomes. Sensitivity analysis was performed to determine threshold values required to change the model outcome. RESULTS: Using average probability estimates from a literature review the decision model recommended initial surveillance. Sensitivity analysis demonstrated that the model depended on the probability of disease recurrence in men followed expectantly after surgery as well as the efficacy of therapeutic radiation. We tested the decision model again for patient groups based on tumor grade, pathological stage, preoperative PSA and number of positive margins. The model recommended initial radiation for patients with low to intermediate grade disease, no evidence of seminal vesicle invasion and multiple positive margins. CONCLUSIONS: The results of our decision analysis imply that immediate radiation may be appropriate for patients with a positive surgical margin(s) and a high likelihood of recurrent local rather than distant disease. This model may be useful to physicians and patients who use individual probability estimates and utility values to determine the preferred course of management after surgery.

Radiotherapy after radical prostatectomy: treatment outcomes and failure patterns.

OBJECTIVES: To define the optimal role for radiotherapy (RT) after radical prostatectomy (RP) and to characterize specific patterns of PSA failure in this setting. METHODS: The records of 105 patients who underwent RT after RP (69 received therapeutic RT because of an elevated prostate-specific antigen [PSA] level, 36 received immediate adjuvant RT) were reviewed. The median follow-up was 35 months after RT and 57 months after RP. Radiation success was defined as achievement and maintenance of a PSA less than 0.2 ng/mL. Preoperative, pathologic, and postoperative characteristics were examined for their ability to predict success after RT. Patterns of PSA recurrence after RT were also examined by determining the PSA nadir, PSA velocity, and timing of androgen-deprivation therapy. RESULTS: Of 105 patients, 47 experienced biochemical failure. Actuarial 3 and 5-year progression-free survival estimates for all patients were 55% and 43%, respectively. Significant favorable predictors of response to RT by multivariate analysis were preoperative PSA less than 20 ng/mL and the use of adjuvant RT. However, patients who received therapeutic RT with a pre-RT PSA less than 1.0 ng/mL demonstrated progression-free outcome equivalent to those who received adjuvant RT. Two distinct patterns of PSA failure were observed on the basis of PSA nadir after RT. Patients whose PSA failed to reach a nadir less than 0.2 ng/mL after RT had progression with a high PSA velocity (1.5 ng/mL/yr). Patients whose PSA reached a nadir less than 0.2 ng/mL but who subsequently had treatment failure progressed later with a lower PSA velocity (0.36 ng/ml/yr). CONCLUSIONS: RT is effective in select patients after RP. Given the low PSA velocity consistent with persistent local disease in nearly 50% of patients in whom RT failed, more effective local therapy is needed after RP in high-risk patients.

Phase I dose escalation of 131I-metaiodobenzylguanidine with autologous bone marrow support in refractory neuroblastoma.

PURPOSE: The analogue 131I-metaiodobenzylguanidine (MIBG), which is specifically targeted to neuroblastoma cells, may provide more effective and less toxic treatment for neuroblastoma than conventional external-beam radiotherapy. We report a dose escalation study of 131I-MIBG to define dose-limiting toxicity without and with autologous bone marrow support. PATIENTS AND METHODS: Thirty patients with relapsed neuroblastoma were treated in groups of six with escalating doses of 3 to 18 mCi/kg of 131I-MIBG. After rapid escalation in the first three patients treated at 3 to 6 mCi/kg, treatment was escalated in 3-mCi/kg increments from 9 to 18 mCi/kg. Autologous tumor-free bone marrow was cryopreserved in all patients receiving 12 mCi/kg and more. Toxicity and response were assessed. RESULTS: Eighty percent of patients who received 12 mC/kg or more experienced grade 4 thrombocytopenia and/or neutropenia. Dose-limiting hematologic toxicity was reached at 15 mCi/kg, at which level two of five assessable patients required bone marrow reinfusion for absolute neutrophil count (ANC) of less than 200/microL for more than 2 weeks, and four of nine at the 18-mCi/kg level. Prolonged thrombocytopenia was common, with failure to become platelet-transfusion independent in nine patients. One patient with extensive prior treatment developed secondary leukemia and three became hypothyroid. Responses were seen in 37% of patients, with one complete response (CR), 10 partial response (PR), three mixed response, 10 stable disease, and six progressive disease. The minimum dose of 131I-MIBG for 10 of the 11 responders was 12 mCi/kg. CONCLUSION: Treatment with 131I-MIBG has mainly hematologic toxicity, which can be abrogated with bone marrow rescue. The high response rate in refractory disease suggests that this agent may be useful in combination with myeloablative chemotherapy and autologous stem-cell rescue to improve outcome in advanced neuroblastoma.