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Purpose: Large setup variability has been observed for prone breast patients due to rotation error. To reduce this uncertainty, we propose a novel implementation of isocentric prone breast method on Elekta linac with couch move assistant (CMA) and on-line KV CBCT. Methods: Daily CBCT is used to evaluate the prone breast patient positioning uncertainty of proposed isocentric technique against our routine manual clinical setup. Clinical setup involves a manual AP shift from the ipsilateral torso tattoos (2PT) to the treatment iso directly underneath and SSD and flash check. While the proposed isocentric prone breast method features an additional contralateral leveling tattoo positioned at mid-level of torso during CT simulation to determine correct patient obliqueness, and an automatic couch shift using Elekta CMA to correct both known distance from 2PT to the iso and daily setup uncertainty. Summary statistics were calculated for a cohort of prone breast patients from our clinic (n=5), and will be updated as more patients get administrated. Results: Small field of view partial CBCT acquisition is optimized to achieve clearance and minimize nominal imaging dose to 0.6cGy per scan to a 16cm phantom. Routine clinical setup uncertainty is 0.3±0.2cm, 0.7±0.4cm and 0.4±0.3cm in S/I, L/R and A/P respectively. Using the isocentric prone breast method, the setup uncertainty could be reduced to 0±0.3cm, 0.3±0.4cm and 0.1±0.3cm if the average couch shift in the 1st week of treatment is applied by CMA to the rest of treatment days. The uncertainty could be further reduced to 0.3±0.1cm, 0±0.1cm and 0±0.2cm with additional contralateral leveling tattoo. The improvement in precision is found to be statistically significant (p

Background There are several management options for patients with squamous cell cancer of the base of tongue. We have had an interest in using primary radiotherapy with or without neck dissection, in an effort to provide optimal oncologic as well as functional outcomes. Methods From 1981 to 1995, 68 patients with primary squamous cell cancer of the base of tongue were managed with primary radiotherapy, with neck dissection added for those who were initially seen with palpable lymph node metastases. Ages ranged from 35 to 77 years (median age, 55 years). There were 59 men and 9 women. T Stage distribution was: T1, 17; T2, 32; T3, 17; T4, 2. Fifty-eight patients (85%) were initially seen with nodal metastases. Initial treatment generally involved external-beam radiotherapy (EBRT) to the primary site and upper neck (54 Gy) and to the low neck (50 Gy). A 192-Ir brachytherapy boost (20–30 Gy) to the base of tongue was done about 3 weeks later, at the same anesthesia used for the neck dissection. All patients had temporary tracheostomy. Follow-up ranged from 1 month to 151 months (median, 36 months). Nine patients received neoadjuvant chemotherapy as part of a larynx-preservation protocol. Results Actuarial 5- and 10-year local control is 89% and 89%, distant metastasis free survival is 91% and 76%, diseasefree survival is 80% and 67%, and overall survival is 86% and 52%, respectively. Complications occurred in 16%. Conclusions Our long term data clearly demonstrate that primary radiotherapy produces excellent oncologic outcomes. © 1998 John Wiley & Sons, Inc. Head Neck 20: 668–673, 1998.

Background Our study is a prospective evaluation of unresectable malignant cancers of the head and neck treated with concomitant chemotherapy and radiotherapy (RT) using delayed accelerated fractionation (concomitant boost). Methods Between January 1988 and March 1995, 82 patients with unresectable cancers of the head and neck were enrolled in this phase II study. Of these, 52 patients were treated and followed for a minimum of 3 years and are the subject of this analysis. All patients had T4 lesions and were stage IV according to the American Joint Committee on Staging Criteria (AJCC). Patients received RT with accelerated fractionation to a total of 70 Gy in 6 weeks using a concomitant-boost technique. Concomitant cis platin (100 mg/M2) was given on days 1 and 22 of RT. Twenty-seven patients received mitomycin-C (7.5 mg/M2) on days 1 and 22, and 1 patient received mitomycin-C on day 1. In addition, 27 patients received adjuvant chemotherapy with cis platin and vinblastine. The mean follow-up was 45 months (range, 36–72 months). The minimum follow-up for surviving patients is 3 years. Results At 3 years, the local control rate was 58%. Three-year local control rates for paranasal sinus, nasopharynx, oropharynx, and larynx/hypopharynx were 78%, 78%, 64%, and 100%, respectively. For all patients, the distant-metastasis-free survival was 56%, and the overall survival rate was 36%. Patients with oral cavity cancers experienced worse overall survival versus other sites, 0% versus 47% (p = .03). Salivary cancers also showed worse survival versus other sites, 0% versus 47%, but was not statistically significant. Severe acute complications occurred in 34% of patients. Treatment-related toxicity also resulted in the death of 2 patients. Severe late complications occurred in 7% of patients. Conclusions Treatment of this poor prognostic group of patients with aggressive chemotherapy and RT produced surprisingly good local control and survival. © 1998 John Wiley & Sons, Inc. Head Neck20: 497–503, 1998.

Background: Thisstudywas conducted to evaluate quality of life in patients treated with primary radiotherapy (RT) for cancer of the base of tongue. Methods: From 1981 to 1990, 36 patients with primary squaradiotherapy. Ages ranged from 35 to 71 years (median, 58 years). T Stage was: T1, n = 11; T2, n = 14; T3, n = 10; T4, n = 1. Thirty-one patients (86%) had palpable cervical lymph node metastases at initial examination (N1, n = 16; N2, n = 11; N3, n = 4). Patients received external beam RT to their primary site and necks, followed by a brachytherapy boost to the tongue. Those with neck nodes also had a neck dissection. The median follow-up is 5 years (minimum, 3 years). Actuarial 5-year local control was 85%; regional control was 96%; distant metastases-free survival was 87.5%; and overall survival, 85%. Twenty-nine of the 30 long-term survivors completed (1) Memorial Symptom Assessment Scale (MSAS), (2) Functional Assessment of Cancer Therapy (FACT), (3) Performance Status Scale for Head and Neck Cancer(PSS), and (4) a sociodemographic and economic questionnaire. At the time of cancer diagnosis, 62% were employed full-time, and 21% were employed part-time; 83% were earning >$20,000/year, and 59% were earning >$60,000/year. Results: At follow-up, annual incomes were similar to those at initial examination. Of those who had been working full-time, 72% were still in full-time work, and of those who had been working part-time, 83% were still in part-time work. Average PSS scores were 90 for eating in public, 96 for understandability of speech, and 68 for normalcy of diet. On the MSAS, the following symptoms had prevalence: >30% xerostomia, difficulty swallowing, decreased energy, pain, worrying, insomnia, cough, drowsy, change In taste, and irritability. Scores on the FACT exceeded published values collected for a mixed cancer population. Conclusions: The overwhelming majority of patients achieved excellent functional status and quality of life and could maintain their prediagnosis earning potential and employment status after primary radiation for advanced base of tongue cancer.

Background Although the standard therapy for locally advanced hypopharyngeal cancer remains surgery and postoperative radiotherapy (RT), alternative treatment approaches include induction chemotherapy and RT. The purpose of this retrospective study was to compare the long-term outcome of these treatments performed in a single institution. Methods Twenty-six patients with advanced, resectable, squamous cell carcinoma of the hypopharynx were treated with induction chemotherapy and definitive RT (group I), reserving laryngectomy for salvage. The induction phase of therapy consisted of 2–3 cycles of cisplatin-based chemotherapy followed by conventional fractionated RT to doses of 66–70 Gy. The outcomes of this group of patients were compared with the outcomes of 30 patients with hypopharyngeal cancer who were treated at our institution with surgery and postoperative RT (group II). The median follow-up times of the surviving patients in groups I and II were 5 and 9 years, respectively. Results The local recurrence-free survival at 5 years from the completion of therapy for group I was 50%, compared with 69% for group II (p = .41). Among patients with T3–T4 primary tumors, the 5-year local control rates were 58% and 59% for groups I and II, respectively (p = .78). The likelihood of larynx preservation, free of local disease at 5 years for group I, was 52%. The 5-year neck recurrence-free survival for groups I and II were 47% and 69%, respectively (p = .66). Among patients with N2–N3 stage disease, the 5-year incidence of neck failure for groups I and II were 73% and 68%, respectively (p = .74). The 5-year distant metastases-free survival for groups I and II were 67% and 57%, respectively (p = .19). The 5-year disease-free survival rates for groups I and II were 30% and 42%, respectively (p = .9). The 5-year overall survival rates for groups I and II were 15% and 22%, respectively (p = .65). Conclusions Nonsurgical therapy for advanced-stage hypopharyngeal cancer provides survivorship comparable with that achieved with standard approaches of surgery and postoperative RT. However, despite the therapy, the outcome is poor. Future studies will need to explore new treatment strategies in an effort to improve upon the outcome for this group of patients. HEAD & NECK 1996;18:405–411 © 1996 John Wiley & Sons, Inc.

Purpose: Large superficial (skin, soft tissue sarcoma) lesions located on curved areas are hard to treat with electrons. The Freiburg Flap (Nucletron, Netherlands) is a flexible mesh style surface which can be easily shaped to fit curved surfaces for reproducible HDR fraction delivery. To understand the fundamental dosimetric differences, a dosimetric comparison was made between HDR plesiotherapy (Freiburg applicator for lesions over 4cm) and external electron beam radiotherapy over cases with varying target curvature (both stylized and clinical cases). Methods: Four stylized cases with variable complexity were created using artificial DICOM axial CT slices and RT structures (a square and three curved structures on a 4.5cm radius cylinder). They were planned using Oncentra v4.3 and exported to Pinnacle v9.6 for electrons planning. The HDR source dwell positions were optimized for the best coverage of the targets using graphical optimization. Electron treatment plans were created in Pinnacle using the same CT and RT structures of three HDR cases with surface lesions previously treated with the Freiburg flap. The En face electron plans used 6-12 MeV electrons and 0.5–1 cm bolus was added to increase surface dose. The electron plans were prescribed to an isodose line to conform to the target. Results:more » For all lesions, the average target dose coverage was similar (D90ave of 100% for HDR vs 101% for electrons). For lesions with high curvature, the HDR coverage was better (D90 102% vs D90 97% for electron). For all cases, adjacent structures high dose region was lower for HDR than electrons (D1cc 100% for HDR vs D1cc 111% for electrons). Conclusion: HDR plesiotherapy offers excellent target conformity for superficial targets similar to electrons. However, for lesions with complex curved surfaces, HDR has the advantage to achieve better dose distributions using graphical optimization to spare adjacent normal tissue while maximizing target coverage.« less

Purpose: Independent validation of IPSA algorithm in obtaining superior target coverage and reduced dose to organs at risk, by comparing with the results of other optimization techniques in HDR brachytherapy.Method and Materials: In a recent prostate HDR brachytherapy protocol study (RTOG‐0321) we used an anatomy based inverse optimization technique known as Inverse Planning Simulated Annealing (IPSA), incorporated as a beta version in the Plato TPS Version 14.2.3 (Nucletron Corp., Veenendaal, The Netherlands) in an effort to satisfy the dose constraints set by the protocol for Prostate, Bladder, Rectum and Urethra. Between the period of June 2005 and November 2006, 20 patients received HDR boost dose of 19 Gy in two fractions to the prostate in addition to an external beam dose of 45 Gy with IMRT technique. 3D Brachytherapytreatment plans were generated using Plato Version 14.2.3. Dosimetry was obtained for the following optimization schemes in Plato, for the same dose constraints for all the patients treated during this time period: Anatomy based IPSA optimization, Geometric optimization on volume and Dose Point optimization on volume. Dose volume histograms were generated for PTV and organs at risk for each optimization method, from which V75 volumes for Rectum, Bladder, and V125 volume for Urethra were determined. Also dose homogeneity index as well as conformal index for the PTV was calculated for each optimization technique. Results: Despite suboptimal needle placement in some implants, using the same dose constraints on all patients, IPSA algorithm was able to comply with the tight RTOG dose constraints for 90% of the patients in this study, whereas it was only 30 % for DPO and only 5% for GO. Conclusion:Anatomy based IPSA optimization proved to be the overall best and fast technique for reducing the dose to organs at risk without compromising target coverage.