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Background The percentage of pelvic lymph node (LN) positivity in cervical cancer patients varies from 19% in early stages to 68% in advanced cases. Thirty-three percent of patients will develop recurrence within 2 years following therapy, and 5-year relative survival for patients with affected regional LNs is 57%. Hence, pelvic LNs need to be included in the definitive plan of radiation treatment for better disease control and longer survival. With conventional radiation therapy, dose escalation was not possible because of small bowel constraints. With higher conformity of intensity-modulated radiotherapy technique, doses to pelvic and abdominal organs can be minimized. The added advantage of simultaneous integrated boost (SIB) is that high dose per fraction is delivered to the gross disease and low dose to the microscopic disease, thereby reducing the total treatment time and improving the therapeutic ratio. Materials and Methods Forty-one patients presenting to the Department of Radiation Oncology, between January 2016 and June 2017, with newly biopsy-proven carcinoma cervix Stage IB to IVA were enrolled in the study, and all the investigations were performed. The radiation dose was delivered using volumetric modulated arc therapy plan according to the dose of 5,000 cGy in 25 fractions to the whole pelvis and 5,500 cGy in 25 fractions to the involved nodes at 220 cGy per fraction using SIB along with weekly cisplatin at 40 mg/m2. After completion of external beam radiation, all the patients received three fractions of brachytherapy to a total dose of 21 Gy. Acute toxicities were assessed using Radiation Therapy Oncology Group criteria. At 3 months after completion of treatment, all the patients were followed up with diffusion-weighted magnetic resonance imaging of abdomen and pelvis to assess the response after 3 months. Results Of 41 carcinoma cervix patients with significantly positive LNs treated with SIB VMAT, 9.8% of the patients (4 patients) had residual nodal disease and 87.8% of the patients (36 patients) had a complete response, and 19.5% (8 patients) had residual disease of primary and 78% (32 patients) had a complete response at 3 months after completion of treatment with only grade I and grade II toxicities. Conclusion Treatment with SIB VMAT in carcinoma cervix patients with significant pelvic LNs shows a very good response with acceptable acute toxicities. But longer follow-up period is required to see if this response translates into better disease-free survival and overall survival.

Introduction This study aimed to estimate the planning target volume (PTV) margin in lung tumors using 4D computed tomography (CT) scan and evaluate other factors that have an effect on tumor motion. Materials and Methods We recruited 43 biopsy-proven, newly diagnosed carcinoma lung patients who were treated with definitive intent from January 2017 to June 2018. The radiation dose was delivered using a 3D conformal radiation therapy (CRT)/intensity-modulated radiotherapy (IMRT)/volumetric modulated arc therapy (VMAT) plan to a dose of 6000 to 6600 cGy in 30 or more fractions to the whole primary. All patients underwent 4D CT scan on the Elekta machine where all the 10 phases of respiration in free breathing were recorded. These phases are fused with CT simulation images, on which gross tumor volume (GTV) and clinical target volume (CTV) are contoured in all phases of respiration. Following this, an internal target volume (ITV) was created by measuring tumor motion all the directions from the center of tumor and PTV was concluded. Results The mean ITV for tumor in all six directions, that is, in superior, inferior, anterior, posterior, medial and lateral directions was 0.9, 0.9, 0.8, 0.9, 0.8, and 0.9 cm, respectively. For coverage of tumor for 90% of patients, the margins required in superior, inferior, anterior, posterior, medial, and lateral directions were 1.3, 1.5, 1.5, 1.4, 1.5, and 1.3 cm, respectively. Other factors such as size of the tumor and location of the tumor did not significantly contribute to PTV changes in our study. Conclusion Mean ITV for tumor in all six directions summed up to be 0.8 cm, but there was significant movement in inferior direction for upper lobe tumors (0.9 cm) (p = 0.008), in medial direction for middle lobe tumors (0.8 cm) (p = 0.05), and in medial direction for lower lobe tumors (0.75 cm) (p = 0.005).