Dosimetric Impact of Voluntary Deep Inspiration Breath Hold (DIBH) in Mediastinal Hodgkin Lymphomas: A Comparative Evaluation of Three Different Intensity Modulated Radiation Therapy (IMRT) Delivery Methods Using Voluntary DIBH and Free Breathing Techniques.

Hodgkin lymphomas are radiosensitive and curable tumors that often involve the mediastinum. However, the application of radiation therapy to the mediastinum is associated with late effects including cardiac and pulmonary toxicities and secondary cancers. The adoption of conformal IMRT and deep inspiration breath- hold (DIBH) can reduce the dose to healthy normal tissues (lungs, heart and breast). We compared the dosimetry of organs at risk (OARs) using different IMRT techniques for two breathing conditions, i.e., deep inspiration breath hold (DIBH) and free breathing. Twenty-three patients with early-stage mediastinal Hodgkin lymphomas were accrued in the prospective study. The patients were given treatment plans which utilized full arc volumetric modulated arc therapy (F-VMAT), Butterfly VMAT (B-VMAT), and fixed field IMRT (FF-IMRT) techniques for both DIBH and free breathing methods, respectively. All the plans were optimized to deliver 95% of the prescription dose which was 25.2 Gy to 95% of the PTV volume. The mean dose and standard error of the mean for each OAR, conformity index (CI), and homogeneity index (HI) for the target using the three planning techniques were calculated and compared using Student's t-test for parametric data and Wilcoxon signed-rank test for non-parametric data. The HI and CI of the target was not compromised using the DIBH technique for mediastinal lymphomas. The mean values of CI and HI for both DIBH and FB were comparable. The mean heart doses were reduced by 2.1 Gy, 2.54 Gy, and 2.38 Gy in DIBH compared to FB for the F-VMAT, B-VMAT, and IMRT techniques, respectively. There was a significant reduction in V5Gy, V10Gy, and V15Gy to the heart (p < 0.005) with DIBH. DIBH reduced the mean dose to the total lung by 1.19 Gy, 1.47 Gy, and 1.3 Gy, respectively. Among the 14 female patients, there was a reduction in the mean right breast dose with DIBH compared to FB (4.47 Gy vs. 3.63 Gy, p = 0.004). DIBH results in lower heart, lung, and breast doses than free breathing in mediastinal Hodgkin Lymphoma. Among the different IMRT techniques, FF-IMRT, B-VMAT, and F-VMAT showed similar PTV coverage, with similar conformity and homogeneity indices. However, the time taken for FF-IMRT was much longer than for the F-VMAT and B-VMAT techniques for both breathing methods. B-VMAT and F-VMAT emerged as the optimal planning techniques able to achieve the best target coverage and lower doses to the OARs, with less time required to deliver the prescribed dose.

Development and Validation of Single-Optimization Knowledge-Based Volumetric Modulated Arc Therapy Model Plan in Nasopharyngeal Carcinomas.

Purpose: Knowledge-based planning (KBP) has evolved to standardize and expedite the complex process of radiation therapy planning for nasopharyngeal cancer (NPC). Herein, we aim to develop and validate the suitability of a single-optimization KBP for NPC. Methods and Materials: Volumetric modulated arc therapy plans of 103 patients with NPC treated between 2016 and 2020 were reviewed and used to generate a KBP model. A validation set of 15 patients was employed to compare the quality of single optimization KBP and clinical plans using the paired t test and the Wilcoxon signed rank test. The time required for either planning was also analyzed. Results: Most patients (86.7%) were of locally advanced stage (III/IV). The median dose received by 95% of the high-risk planning target volume was significantly higher for the KBP (97.1% vs 96.4%; P = .017). The median homogeneity (0.09 vs 0.1) and conformity (0.98 vs 0.97) indices for high-risk planning target volume and sparing of the normal tissues like optic structures, spinal cord, and uninvolved dysphagia and aspiration-related structures were better with the KBP (P < .05). In the blinded evaluation, the physician preferred the KBP plan in 13 out of 15 patients. The median time required to generate the KBP and manual plans was 53 and 77 minutes, respectively. Conclusions: KBP with a single optimization is an efficient and time saving alternative for manual planning in NPC.

Outcomes of Cervical Cancer in HIV-Positive Women Treated With Radiotherapy at a Tertiary Care Center in India.

PURPOSE: There are limited data on management of cervical cancer in women living with HIV in the modern antiretroviral therapy era. The study aimed to evaluate outcomes and toxicities of these patients treated with radiotherapy. MATERIALS AND METHODS: A retrospective analysis of HIV-positive cervical cancer patients treated with radiotherapy between 2011 and 2018 was conducted at a tertiary care center in India. RESULTS: Eighty-two HIV-positive cervical cancer patients treated with radiotherapy were identified. Their median age was 45 years. Seventy-four (90%) patients received radiotherapy with curative-intent and eight patients received palliative radiotherapy. Median CD4 count at the start of treatment was 342 cells/mm3 (interquartile range: 241-531). Among patients planned for definitive radiotherapy, concurrent cisplatin was planned in 52 (70%) patients with a median of four chemotherapy cycles, and 81% (n = 60) patients received brachytherapy. Among patients who received brachytherapy, the median prescription dose was 80 Gy. Seventy-seven patients completed their prescribed treatment. At a median follow-up of 37 months, 3-year disease-free survival of patients planned with curative-intent was 54%. On multivariate analysis, treatment completion was associated with favorable disease-free survival. Grade III/IV acute gastrointestinal toxicity was seen in five (6.8%) patients, whereas 30% patients had grade III/IV acute hematologic toxicity. All these patients completed their planned radiotherapy with good supportive care. CONCLUSION: Standard treatment of chemoradiation should be planned in women living with HIV with well-managed HIV presenting with locally advanced cervical cancer. Our study highlights the need for optimal management of these patients by a multidisciplinary team with intensive supportive care to ensure completion of planned treatment to achieve better outcomes.

Unique challenges and outcomes of young women with breast cancers from a tertiary care cancer centre in India.

BACKGROUND: Young (≤40 years) breast cancers (YBC) are uncommon, inadequately represented in trials and have unique concerns and merit studying. METHODS: The YBC treated with a curative intent between 2015 and 2016 at our institute were analysed. RESULTS: There were 1228 patients with a median age of 36 (12-40) years; 38 (3.1%) had Stage I, 455 (37.1%) - II, 692 (56.3%) -III, and remaining 43 (3.5%) Stage IV (oligo-metastatic) disease; 927 (75.5%) were node positive; 422 (34.4%) were Triple negatives (TNBC), 331 (27%) were HER-2 positive. There were 549 (48.2%) breast conservations and 591 (51.8%) mastectomies of which 62 (10.4%) underwent breast reconstruction. 1143 women received chemotherapy, 617 (53.9%) received as neoadjuvant and 142 (23.1%) had pathological complete response; 934 (81.9%) received adjuvant radiotherapy. At the median follow-up of 48 (0-131) months, 5-year overall and disease-free survival was 79.6% (76.8-82.5) and 59.1% (55.8-62.6). For stage I, II, III and IV, the 5-year overall-survival was 100%, 86.7% (82.8-90.6), 77.3% (73.4-81.2), 69.7% (52.5-86.9) and disease-free survival was 94% (85.9-100), 65.9% (60.3-71.5), 55% (50.5-59.5), and 29.6% (14-45.2) respectively. On multivariate analysis, TNBC and HER-2+ subgroups had poorer survival (p = 0.0035). 25 patients had BRCA mutations with a 5-year DFS of 65.1% (95% CI:43.6-86.6). Fertility preservation was administered in 104 (8.5%) patients; seven women conceived and 5 had live births. Significant postmenopausal symptoms were present in 153 (13%) patients. CONCLUSION: More than half of the YBC in India were diagnosed at an advanced stage with aggressive features leading to suboptimal outcomes. Awareness via national registry and early diagnosis is highly warranted. Menopausal symptoms and fertility issues are prevalent and demand special focus.

Development and clinical validation of Knowledge-based planning for Volumetric Modulated Arc Therapy of cervical cancer including pelvic and para aortic fields.

BACKGROUND AND PURPOSE: Knowledge-based planning (KBP) is based on a model to estimate dose-volume histograms, configured using a library of historical treatment plans to efficiently create high quality plans. The aim was to report configuration and validation of KBP for Volumetric Modulated Arc Therapy of cervical cancer. MATERIALS AND METHODS: A KBP model was configured from the institutional database (n = 125), including lymph node positive (n = 60) and negative (n = 65) patients. KBP Predicted plans were compared with Clinical Plans (CP) and Re-plans (Predicted plan as a base-plan) to validate the model. Model quality was quantified using coefficient of determination R2, mean square error (MSE), standard two-tailed paired t-test and Wilcoxon signed rank test. RESULTS: Estimation capability of the model was good for the bowel bag (MSE = 0.001, R2 = 0.84), modest for the bladder (MSE = 0.008) and poor for the rectum (MSE = 0.02 R2 = 0.78). KBP resulted in comparable target coverage, superior organ sparing as compared to CP. Re-plans outperformed CP for the bladder, V30 (66 ± 11% vs 74 ± 11%, p < .001), V40 (48 ± 14% vs 52 ± 14%, p < .001), however sparing was modest for the bowel bag V30 (413 ± 191cm3 vs 445 ± 208cm3, p = .037) V40 (199 ± 105cm3 vs 218 ± 127cm3, p = .031). All plans were comparable for rectum, while KBP resulted in significant sparing for spinal cord, kidneys and femoral heads. CONCLUSION: KBP yielded comparable and for some organs superior performance compared to CP resulting in conformal and homogeneous target coverage. Improved organ sparing was observed when individual patient geometry was considered.

Cervical Cancer Treatment in HIV-Positive Patients: A Survey of Treatment Practices in India.

PURPOSE: Chemoradiation remains a challenge in women living with HIV (WLWH) and cervical cancer primarily because of concerns regarding immune status. With limited literature available to help guide the management of these patients, clinical practices among oncologists are variable across India. Hence, we conducted a survey among radiation oncologists in India to assess the patterns of current practices of treating cervical cancer with chemoradiation in WLWH. MATERIALS AND METHODS: A questionnaire consisting of 12 questions related to the treatment of cervical cancer in WLWH was distributed to radiation oncologists at two national conferences in India. RESULTS: The questionnaire was distributed to 105 radiation oncologists, and 90 (85.7%) responses were received. 95.5% of respondents reported that patients with advanced cervical cancer constituted the majority of their practice. Chemoradiation was reported as the most common modality of planned treatment. Ninety-four percentage of respondents reported that they referred patients to an antiretroviral therapy clinic before starting definitive treatment. The majority of respondents (68%) do not plan for concurrent chemotherapy if CD4 counts were < 200 cells/mm3. As many as 50% of respondents reported that they would only start antiretroviral therapy when CD4 counts drop. Poor social support (37.6%), concurrent infections during treatment (28.2%), acute toxicities (21.2%), and poor nutrition (13%) were cited as the most common reasons for treatment interruption in cervical cancer patients with HIV. CONCLUSION: This survey highlights the prevalent inconsistencies in treatment protocols employed by radiation oncologists in India for the management of locally advanced cervical cancer in WLWH. It also reflects the need for social and nutritional support to help improve compliance and thereby improve outcomes in these patients.