Expanding role of radiotherapy in adenoid cystic carcinoma of the tracheobronchial tree: a new horizon.

BACKGROUND: Primary adenoid cystic carcinomas (ACCs) of central trachea-bronchi system are rare and heterogeneous tumors. Definitive radiotherapy (RT) is the recommended treatment in surgically unresectable or incomplete resection or in the presence of severe comorbidities. OBJECTIVE: To evaluate the clinical features and outcomes of patients with ACC of trachea-bronchi treated with radiotherapy. METHODS: Retrospective medical records review was done in all patients with histologically confirmed ACC of trachea-bronchi between January 2010 and December 2019. Patient disease and treatment characteristics and toxicity data were analyzed. Overall survival (OS), local recurrence-free survival (LRFS), and distant metastasis-free survival (DMFS) were computed using Kaplan-Meier method (log-rank test). RESULTS: Nineteen patients (10 women and 9 men) were included in this analysis with median age of 40 years (range, 14-70). Of these patients, 63.2% (n = 12) presented in stage IV disease. Twelve and three patients received definitive (median dose 67.8 Gy) and adjuvant (median dose 50 Gy) RT, respectively. The median follow-up was 42.5 months (range, 4-120); 15 patients were alive and 4 were dead at that time. Local recurrence or progression was observed in 52.6% and distant metastasis found in 47.3% of patients. The 5-year OS, LRFS, and DMFS for all patients were 81.2%, 52.8%, and 39.6%, respectively. Baseline lymph node involvement showed significant impact on OS (56.3% vs 100%, p = 0.011). Among patients receiving definitive RT, patients with higher RT dose (⩾66 Gy) had significantly better survival outcomes (5-year LRFS: 75% vs 16.7%, p = 0.013). CONCLUSION: Definitive RT is an exemplary treatment for unresectable disease. Higher dose is recommended to improve long-term outcomes.

Impact of Immunohistochemical profiling of Glioblastoma multiforme on clinical outcomes: Real-world scenario in resource limited setting.

OBJECTIVE: Intuition into the molecular pathways of glioblastoma multiforme (GBM) has changed the diagnostic, prognostic, and therapeutic approaches. We investigated the influence of various clinical and molecular prognostic factors on survival outcomes in radically treated GBM patients. METHODS: Medical records of 160 GBM patients treated between January-2012 and December-2018 with surgery followed by post-operative external beam radiotherapy (EBRT) with/without temozolomide (TMZ) were reviewed. Immunohistochemical (IHC) assays were performed for IDH1mutation, ATRX loss, TP53 overexpression and Ki-67% index. Apart from disease and treatment-related factors' influence on clinical outcomes, the impact of IHC markers in prognostication was analyzed using appropriate statistical tests. RESULTS: The median overall survival (OS) was 14 months. EBRT with concurrent TMZ was given to 60% of patients and 42.5% completed the standard Stupp-protocol. Significant improvements in OS was observed in patients aged ≤ 50years (2-year OS: 22.1% vs. 12.5%, p = 0.001), those who underwent gross total resection (2-year OS: 21.8% vs. 12.8%, p = 0.002), received concurrent TMZ (21.9% vs. 12.5%, p = 0.005), completed the entire Stupp-protocol (2-year OS: 23.4% vs. 6.5%, p = 0.000), and with Ki-67 index <20% (2-year OS: 23.3% vs. 11.6%, p = 0.015). On multivariate analysis, IDH1 mutation, ATRX loss, TP53 expression, and Ki-67 ≤ 20% were significant prognosticators of outcomes. CONCLUSION: GBM patients treated with concurrent chemoradiation and those who completed the full Stupp-protocol experienced better survival outcomes. Molecular biology significantly impacts clinical outcomes and plays a key deterministic role in newer management strategies.

Hurdles in radiation planning for glioblastoma: Can delayed-contrast enhanced computed tomography be a potential solution?

OBJECTIVE: Conformal radiation is the standard of care in treatment of glioblastoma. Although co-registration of magnetic resonance imaging (MRI) with early contrast enhanced computed tomography (CECT) is recommended for target delineation by consensus guidelines, ground realities in developing countries often result in availability of less-than-ideal MR sequences for treatment planning. Purpose of this study is to analyze the impact of incorporation of delayed-CECT sequences for radiation planning in glioblastomas, as an adjunct or alternative to MRI. METHODS: Case records of all patients of glioblastoma treated at our center between 2011 and 2014 were retrospectively evaluated. Gross treatment volumes were delineated on T1 contrast MRI (m-GTV), early CECT (e-GTV) and delayed CECT (d-GTV); volumetric comparisons were made using repeated measures analysis of variance and pair-wise analysis. RESULTS: Although 96% of registered patients underwent postoperative MRI, only 38% of them had desirable sequences suitable for co-registration. Median duration between acquisition of postoperative MRI and surgery was 45 days (range, 33-60), whereas that between MRI and treatment-planning CT was 5 days (range, 1-10). Statistically significant differences (P < 0.0001) were obtained between mean volumes of e-GTV (41.20cc), d-GTV (58.09cc) and m-GTV (60.52cc). Although the mean GTV increased by 46% between early CECT and MRI, the difference was only 4% between delayed CECT and MRI. CONCLUSION: Delayed CECT is superior to early CECT for co-registration with MRI for target delineation, especially when available MR sequences are less-than-ideal for treatment planning, and can be considered as the most appropriate adjunct as well as an alternative to MRI, compared to early CECT.