Introduction: Despite technical developments in treatment delivery, radiation-induced lung toxicity remains a crucial problem in thoracic radiotherapy. As patients with lung cancer present with compromised lung function, reproducibility of FEV1,FVC helps to ensure pulmonary function tests as important predictors of patients ability to undergo surgical resection and radical radiotherapy. Hence we evaluate the changes in pulmonary function with concurrent chemoradiation.

Materials and Methods: This is a prospective study conducted at MNJIO and RCC to evaluate the changes in pulmonary functions in total 60 patients who had received ³60 Gy radiotherapy, chemotherapy for primary NSCLC who had undergone pulmonary function tests (PFTs) before and within one year after treatment. Before every cycle of chemotherapy, pulmonary function tests were done. Postradiation PFT values (percentage of predicted) were evaluated amongst individual patients compared to the same patient’s preradiation value at the following time intervals of 0 to 4 months, 5 to 8 months, and 9 to 12 months.

Results: Lung diffusing capacity for carbon monoxide (DLCO) is reduced in the majority of patients along the 3 time periods after radiation, whereas the forced expiratory volume in 1 second per unit of vital capacity (FEV1/VC) showed an increase and decrease after radiation in a similar percentage of patients. There were baseline differences (stage, RT dose, concurrent chemotherapy) among the radiation technology groups. On multivariate analysis, the following features were associated with larger post treatment declines in DLCO: pretreatment DLCO, gross tumor volume (GTV), Only pretreatment DLCO was associated with larger posttreatment declines in FEV1/VC.

Conclusions: Lung diffusing capacity for carbon monoxide is reduced in the majority of the patients after chemoradiation including gross tumour volume and preraditional lung function, all of which could be used to estimate the impact of radiation therapy on an individual’s respiratory status, possibly in the setting of objective models that could aid in counselling patients prior to treatment.

Nindra Armugam is a dedicated and experienced Consultant Radiation Oncologist with strong expertise in modern radiotherapy techniques and cancer treatment planning. He completed his MBBS from SV Medical College, Tirupathi, in 1998, and later obtained his MD in Radiotherapy from MNJIO & RCC, India, in 2005. His early professional experience includes working as a Registrar in Radiotherapy at Kamineni Hospital, Hyderabad (January 2006 – March 2006). He has 9 publications, including 2 Hi indexed articles. He possesses extensive hands-on experience in advanced radiation therapy techniques, including RapidArc, IGRT (Image-Guided Radiotherapy), IMRT (Intensity-Modulated Radiotherapy), 3DCRT, and brachytherapy, with a special interest in brachytherapy and stereotactic treatments such as CyberKnife. He is proficient in multiple radiation treatment planning and contouring systems such as ARIA (Varian), Sunrise Plato, FocalSim, BrainLab, ADAC, Oncentra planning systems, and the Coherence dosimetrist contouring workstation. In addition, he has practical experience working with several radiation therapy machines, including RapidArc systems, Tomotherapy, Trilogy, Novalis Tx, Clinac 6EX/2100C/2100CD, Theratron, Equinox, and Bhabhatron-II. With a strong commitment to patient-centered care, he emphasizes developing effective interpersonal relationships within multidisciplinary healthcare teams. As a professional goal, he aims to contribute meaningfully to institutional growth while utilizing clinical expertise, technical knowledge, and academic experience to improve cancer treatment outcomes and patient care. He also serves as an editorial board member of several reputed journals.