Purpose: To report the outcomes of patients with favorable risk oropharyngeal cancer that underwent adjuvant radiation therapy with omission of the primary site from the clinical target volume (CTV). Material/Methods: A retrospective study of 40 patients treated with transoral surgery (TOS) followed by neck only radiation using intensity modulated radiation therapy (IMRT) with exclusion of the primary site. For all patients, a CTV of the primary surgical bed was contoured to obtain the estimated incidental dose to the primary site. Results: Median follow-up was 51 months (range, 13-155 months). The median radiation therapy (RT) dose to the neck was 6000 cGy (range, 5400-6400 cGy). The mean incidental dose to the primary tonsillar site was 4320 cGy (SD ± 480 cGy) and to the primary base of tongue site was 4060 cGy (SD ± 420 cGy). There were no local failures and only 1 regional failure, resulting in 97.5% locoregional control rate at 4 years. Two patients developed distant metastases, without evidence of locoregional recurrence, for a 4-year overall survival rate of 97%. Conclusions: Our analysis suggests that mucosal sparing RT after TOS in favorable risk oropharyngeal cancer patients may provide comparable oncologic and improved functional outcomes compared to conventional treatment in selected patients.
Proposed prognostic scoring system evaluating risk factors for biochemical recurrence of prostate cancer after salvage radiation therapy
Objective To update a previously proposed prognostic scoring system that predicts risk of biochemical recurrence ( BCR ) after salvage radiation therapy ( SRT ) for recurrent prostate cancer when using additional patients and a PSA value of 0.2 ng/ mL and rising as the definition of BCR . Patients and Methods We included 577 patients who received SRT for a rising PSA after radical prostatectomy in this retrospective cohort study. Clinical, pathological, and SRT characteristics were evaluated for association with BCR using relative risks ( RR s) from multivariable Cox regression models. Results With a median follow‐up of 5.5 years after SRT , 354 patients (61%) experienced BCR . At 5 years after SRT , 40% of patients were free of BCR . Independent associations with BCR were identified for the PSA level before SRT ( RR [doubling]: 1.25, P < 0.001), pathological tumour stage ( RR [T3a vs T2] 1.21, P = 0.19; RR [T3b/T4 vs T2] 2.09, P < 0.001; overall P < 0.001), Gleason score ( RR [7 vs <7] 1.63, P < 0.001; RR [8–10 vs <7] 2.28, P < 0.001; overall P < 0.001), and surgical margin status ( RR [positive vs negative] 0.71, P = 0.003). We combined these four variables to create a prognostic scoring system that predicted BCR risk with a c ‐index of 0.66. Scores ranged from 0 to 7, and 5‐year freedom from BCR for different levels of the score was as follows: Score = 0–1: 66%, Score = 2: 46%, Score = 3: 28%, Score = 4: 19%, and Score = 5–7: 15%. Conclusion We developed a scoring system that provides an estimation of the risk of BCR after SRT . These findings will be useful for patients and physicians in decision making for radiation therapy in the salvage setting.
Six-year Outcome of a Prospective Study Evaluating Tumor Bed Boost with Intra-operative Electron Irradiation Followed by whole-Breast Irradiation for Early-Stage Breast Cancer
We have developed a treatment planning protocol for intensity‐modulated radiation therapy of the prostate using commercially available inverse planning software. Treatment plans were developed for ten patients using the Corvus version 3.8 planning system, testing various prescription options, including tissue types, dose volume histogram values for the target and normal structures, beam arrangements, and number of intensity levels. All plans were scaled so that 95% of the clinical target volume received 75.6 Gy; mean doses to the prostate were typically 79 Gy. The reproducibility of the inverse planning algorithm was tested by repeating a set of the plans five times. Plans were deemed acceptable if they satisfied predefined dose constraints for the targets and critical organs. Figures of merit for target coverage, target dose uniformity, and organ sparing were used to rank acceptable plans. Certain systematic behaviors of the optimizer were noted: the high dose regions for both targets and critical organs were 5–10 Gy more than prescribed; reducing bladder and rectum tolerance increased the range of doses within the target; increasing the number of fields incrementally improved plan quality. A set of planning parameters was found that usually satisfied the minimum requirements. Repeating the optimization with different beam order produced similar but slightly different dose distributions, which was sometimes useful for finding acceptable solutions for difficult cases. The standard set of parameters serves as a useful starting point for individualized planning.PACS number(s): 87.53.–j, 87.90.+y
Combined Prostate Brachytherapy and Short-Term Androgen Deprivation Therapy as Salvage Therapy for Locally Recurrent Prostate Cancer After External Beam Irradiation