A multicenter retrospective analysis of patients with nasopharyngeal carcinoma treated in IMRT era from a nonendemic population: Turkish Society for Radiation Oncology Head and Neck Cancer Group Study (TROD 01-001).

BACKGROUND: We aimed to evaluate patients with nasopharyngeal carcinoma (NPC) in a nonendemic population. METHODS: In a national, retrospective, multicenteric study, 563 patients treated with intensity modulated radiotherapy at 22 centers between 2015 and 2020 were analyzed. RESULTS: Median age was 48 (9-83), age distribution was bimodal, 74.1% were male, and 78.7% were stage III-IVA. Keratinizing and undifferentiated carcinoma rates were 3.9% and 81.2%. Patients were treated with concomitant chemoradiotherapy (48.9%), or radiotherapy combined with induction chemotherapy (25%) or adjuvant chemotherapy (19.5%). After 34 (6-78) months follow-up, 8.2% locoregional and 8% distant relapse were observed. Three-year overall survival was 89.5% and was lower in patients with age ≥50, male sex, keratinizing histology, T4, N3 and advanced stage (III-IVA). CONCLUSIONS: Patients with NPC in Turkey have mixed clinical features of both east and west. Survival outcomes are comparable to other reported series; however, the rate of distant metastases seems to be lower.

Outcomes of carotid sparing intensity-modulated radiotherapy for early stage glottic cancer in 201 patients: Multicenter study of Turkish Radiation Oncology Society/TROD-01-007.

BACKGROUND: To assess and report clinical outcomes after carotid sparing intensity-modulated radiotherapy for early stage laryngeal cancer. METHODS: We retrospectively analyzed 201 patients with early stage glottic laryngeal cancer treated with carotid sparing intensity-modulated radiotherapy (IMRT)/volumetric modulated arc therapy (VMAT) techniques in six TROD centers. RESULTS: After a median follow-up of 31 months the actuarial 1- and 3-year local and locoregional control rates were 99.4% and 94.7%, 98.4% and 93%, respectively. T classification, anterior commissure involvement, IMRT technique, and type of fractionation were not found to be prognostic for local control. Overall, eight patients had lost their organ function due to recurrence or toxicity. Grade 3 and 4 acute laryngeal edema was seen in eight (4%) and one (0.5%) of patients, respectively. Grade 3 and 4 late laryngeal edema developed in two (1%) and one patient (0.5%), respectively. CONCLUSION: Oncologic outcomes of patients treated with carotid sparing IMRT were excellent; comparable with historical series, with acceptable side effects. Longer follow-up is needed to estimate long term effect on stroke.

Outcome and safety analysis of endometrial cancer patients treated with postoperative 3D-conformal radiotherapy or intensity modulated radiotherapy.

BACKGROUND: We sought to analyze the toxicity rates and the treatment outcomes in endometrial cancer (EC) patients treated with postoperative three-dimensional conformal radiotherapy (3DCRT) and intensity-modulated radiotherapy (IMRT). MATERIAL AND METHODS: The clinical data of 646 EC patients treated with postoperative adjuvant 3DCRT (265 patients, 41%) or with IMRT (381 patients, 59%) between April 2007 and August 2019 were retrospectively analyzed. The primary endpoints were treatment-related acute and late gastrointestinal (GI) and genitourinary (GU) toxicities. The secondary endpoints were LC and overall survival (OS) and disease-free survival (DFS). RESULTS: Median follow-up time was 37 months. The rates for acute GI and GU toxicities of any grade for the entire group were 55.6% and 46.8%, respectively. Acute grade ≥2 GI toxicity was significantly less in patients treated with IMRT compared to those treated with 3DCRT (11.0% vs. 19.2%, p=.004). However, no significant difference grade ≥2 GU toxicities was observed between the 3DCRT and IMRT groups (15.1% vs. 11.0%; p=.15). Acute grade ≥2 GI and GU toxicities were higher in patients receiving systemic chemotherapy, while paraaortic field irradiation increases only the risk of acute grade ≥2 GI toxicity. Estimated 3-year late grade ≥3 GI toxicity rates in the 3DCRT- and IMRT-treated patients were 4.6% and 1.9% (p= .03), respectively. The patients treated with adjuvant ChT had higher rates of late serious GI complications than those without adjuvant ChT. No significant difference in terms of survival and disease control was observed between the 3DCRT and IMRT treatment groups. No significant factor for LC was found in the multivariate analysis. CONCLUSION: In this multicentric study involving one of largest patient population, we found that IMRT-treated EC patients showed comparable clinical outcomes but with a lower incidence of GI toxicities compared with those treated with 3DCRT.

Definitive Chemoradiotherapy in Elderly Cervical Cancer Patients: A Multiinstitutional Analysis.

OBJECTIVE: The aim of the study was to investigate the prognostic factors for survival and treatment-related toxicities in older (≥65 years) cervical cancer patients treated with definitive chemoradiotherapy. In addition, we sought to compare the outcomes between the older elderly (≥75 years) and their younger old counterparts (age, 65-74 years). MATERIALS AND METHODS: We retrospectively reviewed medical records from 269 biopsy-proven nonmetastatic cervical cancer patients treated with external radiotherapy and intracavitary brachytherapy at the departments of radiation oncology in 2 different universities. The prognostic factors for survival, local control, and distant metastasis (DM) were analyzed. RESULTS: The median follow-up time was 38.8 months (range, 1.5-175.5 months) for the entire cohort and 70.0 months (range, 6.1-175.7 months) for survivors. The 2- and 5-year overall survival (OS), disease-free survival (DFS), and cause-specific survival rates were 66% and 42%, 63% and 39%, and 72% and 55%, respectively. Patients 75 years or older showed significantly worse OS compared with patients aged 65 to 74 years but showed no significant difference in DFS. The 2- and 5-year local control rates were 86% and 71%, respectively. The incidences of DMs at 2 and 5 years were 22% and 30%, respectively. In multivariate analysis, vaginal infiltration and lymph node metastasis were predictive of OS, DFS, local recurrence, and DM. Concomitant chemotherapy was predictive of OS, DFS, and local recurrence, and larger tumor (>4 cm) was a significant prognostic factor for local recurrence. None of the patients had toxicity that necessitated the discontinuation of radiotherapy. All patients were evaluable for acute toxicity, and no grade higher than 3 adverse events occurred during external beam radiation therapy or brachytherapy. CONCLUSIONS: Although age limited the delivery of aggressive treatment, concurrent chemoradiotherapy in elderly patients associated with improved outcomes similar as in younger counterparts without increasing serious acute and late toxicities.

The dosimetric impact of implants on the spinal cord dose during stereotactic body radiotherapy.

BACKGROUND: The effects of spinal implants on dose distribution have been studied for conformal treatment plans. However, the dosimetric impact of spinal implants in stereotactic body radiotherapy (SBRT) treatments has not been studied in spatial orientation. In this study we evaluated the effect of spinal implants placed in sawbone vertebra models implanted as in vivo instrumentations. METHODS: Four different spinal implant reconstruction techniques were performed using the standard sawbone lumbar vertebrae model; 1. L2-L4 posterior instrumentation without anterior column reconstruction (PI); 2. L2-L4 anterior instrumentation, L3 corpectomy, and anterior column reconstruction with a titanium cage (AIAC); 3. L2-L4 posterior instrumentation, L3 corpectomy, and anterior column reconstruction with a titanium cage (PIAC); 4. L2-L4 anterior instrumentation, L3 corpectomy, and anterior column reconstruction with chest tubes filled with bone cement (AIABc). The target was defined as the spinous process and lamina of the lumbar (L) 3 vertebra. A thermoluminescent dosimeter (TLD, LiF:Mg,Ti) was located on the measurement point anterior to the spinal cord. The prescription dose was 8 Gy and the treatment was administered in a single fraction using a CyberKnife® (Accuray Inc., Sunnyvale, CA, USA). We performed two different treatment plans. In Plan A beam interaction with the rod was not limited. In plan B the rod was considered a structure of avoidance, and interaction between the rod and beam was prevented. TLD measurements were compared with the point dose calculated by the treatment planning system (TPS). RESULTS AND DISCUSSION: In plan A, the difference between TLD measurement and the dose calculated by the TPS was 1.7 %, 2.8 %, and 2.7 % for the sawbone with no implant, PI, and PIAC models, respectively. For the AIAC model the TLD dose was 13.8 % higher than the TPS dose; the difference was 18.6 % for the AIABc model. In plan B for the AIAC and AIABc models, TLD measurement was 2.5 % and 0.9 % higher than the dose calculated by the TPS, respectively. CONCLUSIONS: Spinal implants may be present in the treatment field in patients scheduled to undergo SBRT. For the types of implants studied herein anterior rod instrumentation resulted in an increase in the spinal cord dose, whereas use of a titanium cage had a minimal effect on dose distribution. While planning SBRT in patients with spinal reconstructions, avoidance of the rod and preventing interaction between the rod and beam might be the optimal solution for preventing unexpectedly high spinal cord doses.