And Yet It Moves: Clinical Outcomes and Motion Management in Stereotactic Body Radiation Therapy (SBRT) of Centrally Located Non-Small Cell Lung Cancer (NSCLC): Shedding Light on the Internal Organ at Risk Volume (IRV) Concept.

The internal organ at risk volume (IRV) concept might improve toxicity profiles in stereotactic body radiation therapy (SBRT) for non-small cell lung cancer (NSCLC). We studied (1) clinical aspects in central vs. peripheral tumors, (2) the IRV concept in central tumors, (3) organ motion, and (4) associated normal tissue complication probabilities (NTCPs). We analyzed patients who received SBRT for NSCLC (clinical aspects, n = 78; motion management, n = 35). We found lower biologically effective doses, larger planning target volume sizes, higher lung doses, and worse locoregional control for central vs. peripheral tumors. Organ motion was greater in males and tall patients (bronchial tree), whereas volume changes were lower in patients with a high body mass index (BMI) (esophagus). Applying the IRV concept (retrospectively, without new optimization), we found an absolute increase of >10% in NTCPs for the bronchial tree in three patients. This study emphasizes the need to optimize methods to balance dose escalation with toxicities in central tumors. There is evidence that organ motion/volume changes could be more pronounced in males and tall patients, and less pronounced in patients with higher BMI. Since recent studies have made efforts to further subclassify central tumors to refine treatment, the IRV concept should be considered for optimal risk assessment.

Outcomes of Multimodal Treatment in Elderly Patients with Localized Non-Small Lung Cancer from a Radiation Oncology Point of View: Special Focus on Low-Dose Cisplatin.

Identification of the optimal treatment strategy is challenging in elderly with localized non-small cell lung cancer (NSCLC). Concurrent chemotherapy with low-dose cisplatin represents an option for elderly. Outcomes (1) in elderly (≥70 years, n = 158) vs. younger patients (n = 188) and (2), independently of age, in definitive radiochemotherapy, with low-dose cisplatin (n = 125) vs. cisplatin/vinorelbine (n = 76) were studied. Elderly included more males, had a lower Karnofsky index, more comorbidities, and lower stages. Low-dose cisplatin patients (vs. cisplatin/vinorelbine) had higher age, more comorbidities, and lower stages. We observed reduced dermatitis and dysphagia and increased anemia and thrombocytopenia in elderly vs. younger patients, without increased ≥grade 3 toxicities. Low-dose cisplatin was less toxic than cisplatin/vinorelbine. Survival outcomes were lower in elderly vs. younger and comparable between low-dose cisplatin and cisplatin/vinorelbine. In elderly, gender, Karnofsky index, stage, and multimodal treatment (including additional surgery/systemic therapy) were identified as prognostic factors. In conclusion, we found evidence for an acceptable toxicity profile and the need for improvement of outcomes in elderly with localized NSCLC. Multimodal strategies (including additional surgery/systemic treatment) showed favorable outcomes and should be reasonably considered in elderly who are deemed fit enough. Low-dose cisplatin should be discussed on an individual basis due to favorable toxicity and outcomes.