Faculty Bibliography

PURPOSE: Although high-dose-rate brachytherapy (HDRBT) offers significant advantages over low dose rate brachytherapy, there are scant data on improved local control (LC) and treatment-related complications in patients with recurrent head and neck (H&N) cancers. We report our preliminary results in patients with recurrent H&N cancers treated with interstitial HDRBT. METHODS AND MATERIALS: Thirty patients with recurrent H&N cancers were treated with HDRBT between September 2003 and October 2005. Seventy-seven percent (23/30) of the patients had either local or regional recurrence in the area of previous external beam radiation therapy. The treatment sites were oral cavity/oropharynx (11/30), neck (10/30), face/nasal cavity (6/30), and parotid bed (3/30). Whereas 18 patients underwent surgical resection followed by HDRBT, 3 patients were treated with combined external beam radiation and HDRBT, and the remaining 9 were treated with HDRBT alone. The dose and fractionation schedules used were 3.4Gy twice per day (b.i.d.) to 34Gy for postoperative cases, 4Gy b.i.d. to 20Gy when combined with 40-50Gy external beam, and 4Gy b.i.d. to 40Gy for definitive treatment. HDRBT was initiated 5 days after catheter placement to allow for tissue healing. RESULTS: With a median followup of 12 months, 6 local recurrences were observed 1-10 months after the procedure. The 2-year LC and overall survival outcomes for the entire group were 71% and 63%, respectively. Patients treated with surgical resection and HDRBT had an improved 2-year LC compared to the patients treated with HDRBT+/-external beam radiation alone (88% vs. 40%, p=0.05). Six Grade II and four Grade III complications were noted in five patients, all observed in the postoperative HDRBT group. CONCLUSION: The preliminary results of HDRBT indicate an acceptable LC and morbidity in recurrent H&N cancers. A planned surgical resection followed by HDRBT is associated with improved tumor control in these high-risk patients. Based on these encouraging results, prospective clinical trials are warranted using HDRBT in recurrent H&N cancers to decrease late toxicity

In this paper we put forward the claim that the combination of low dose-rate brachytherapy (BRT) and fractionated external-beam radiotherapy (EBRT) may, when planned to take advantage of the relative advantages of each of these two modalities, result in enhanced tumor dose with no penalties to organs at risk. The concept of iso-effective dose (IED) serves the role of common currency for fusing BRT and EBRT and, for evaluation purposes, converting back the resulting IED distribution into a biologically equivalent plan delivered by any single modality. If we accept this view, there are further questions that must be answered regarding practical matters. We show how to deal with these questions by describing an actual patient plan.

PURPOSE/OBJECTIVE:To perform a retrospective analysis of patients with paranasal sinus (PNS) cancer treated with postoperative radiotherapy (RT) at Memorial Sloan-Kettering Cancer Center. METHODS AND MATERIALS/METHODS:Between January 1987 and July 2005, 85 patients with PNS and nasal cavity cancer underwent postoperative RT. Most patients had squamous cell carcinoma (49%; n = 42), T4 tumors (52%; n = 36), and the maxillary sinus (53%; n = 45) as the primary disease site. The median radiation dose was 63 Gy. Of the 85 patients, 76 underwent CT simulation and 53 were treated with either three-dimensional conformal RT (27%; n = 23) or intensity-modulated RT (35%; n = 30). Acute and late toxicities were scored according to the Radiation Therapy Oncology Group radiation morbidity scoring criteria. RESULTS:With a median follow-up for surviving patients of 60 months, the 5-year estimates of local progression-free, regional progression-free, distant metastasis-free, disease-free, and overall survival rates were 62%, 87%, 82%, 55%, and 67%, respectively. On multivariate analysis, squamous cell histology and cribriform plate involvement predicted for an increased likelihood of local recurrence, and squamous cell histologic features predicted for worse overall survival. None of the patients who underwent CT simulation and were treated with modern techniques developed a Grade 3-4 late complication of the eye. CONCLUSION/CONCLUSIONS:Complete surgical resection followed by adjuvant RT is an effective and safe approach in the treatment of PNS cancer. Emerging tools, such as three-dimensional conformal treatment and, in particular, intensity-modulated RT for PNS tumors, may minimize the occurrence of late complications associated with conventional RT techniques. Local recurrence remains a significant problem.

PURPOSE/OBJECTIVE:To assess long-term prostate-specific antigen (PSA) outcome after permanent prostate brachytherapy (BT) and identify predictors of improved disease-free survival. METHODS AND MATERIALS/METHODS:Eleven institutions combined data on 2,693 patients treated with permanent interstitial BT monotherapy for T1-T2 prostate cancer. Of these patients, 1,831 (68%) were treated with I-125 (median dose, 144 Gy) and 862 (32%) were treated with Pd-103 (median dose, 130 Gy). Criteria for inclusion were: available pre-BT PSA, BT > or =5 years before data submission, BT between 1988-1998, and no androgen deprivation before failure. The median follow-up was 63 months. RESULTS:Among patients where the I-125 dose to 90% of the prostate (D90) was > or =130 Gy, the 8-year PSA relapse-free survival (PRFS) was 93% compared with 76% for those with lower D90 dose levels (p < 0.001). A multivariable analysis identified tumor stage (p = 0.002), Gleason score (p < 0.001), pretreatment PSA level (p < 0.001), treatment year (p = 0.001), and the isotope used (p = 0.004) as pretreatment and treatment variables associated with PRFS. When restricted to patients with available postimplantation dosimetric information, D90 emerged as a significant predictor of biochemical outcome (p = 0.01), and isotope was not significant. The 8-year PRFS was 92%, 86%, 79%, and 67%, respectively, for patients with PSA nadir values of 0-0.49, 0.5-0.99, 1.0-1.99, and >2.0 ng/mL (p < 0.001). Among patients free of biochemical relapse at 8 years, the median nadir level was 0.1 ng/mL, and 90% of these patients achieved a nadir PSA level <0.6 ng/mL. CONCLUSIONS:Outcome after permanent BT for prostatic cancer relates to tumor stage, Gleason score, pretreatment PSA, BT year, and post-BT dosimetric quality. PSA nadir < or =0.5 ng/mL was particularly associated with durable long-term PSA disease-free survival. The only controllable factor to impact on long-term outcome was the D90 which is a reflection of implant quality.

PURPOSE/OBJECTIVE:To report the 5-year tumor control and toxicity outcomes for patients with localized prostate treated with I-125 permanent implantation using an intraoperative real-time conformal planning technique. METHODS AND MATERIALS/METHODS:Between January 1998 and June 2002, 367 patients with prostate cancer were treated with I-125 permanent interstitial implantation using a transrectal ultrasound-guided approach. Real-time intraoperative treatment planning which incorporated inverse planning optimization was used. The median follow-up time was 63 months. RESULTS:The median V100 and D90 were 96% and 173 Gy, respectively. In 96% of cases a D90 of >140 Gy was achieved. The median urethral and rectal doses were 100% and 33% of the prescription doses, respectively. The 5-year PSA relapse-free survival outcomes for favorable and intermediate risk patients according to the ASTRO definition were 96% and 89%, respectively. In these patients no dosimetric parameter was identified which influenced the biochemical outcome. Of 38% who developed acute Grade 2 urinary symptoms, 63% had resolution of their symptoms within a median time of 6 months. The incidence of late rectal and urinary Grade 3 or higher toxicities were 1% and 4%, respectively. Seven percent (n = 27) developed late rectal bleeding (Grade 2) and 19% experienced late Grade 2 urinary symptoms. CONCLUSION/CONCLUSIONS:Real-time intraoperative planning consistently achieved optimal coverage of the prostate with the prescription dose with concomitant low doses delivered to the urethra and rectum. Biochemical control outcomes were excellent at 5 years and late toxicity was unusual. These data demonstrate that real-time planning methods can consistently and reliably deliver the intended dose distribution to achieve an optimal therapeutic ratio between the target and normal tissue structures.