Publications by authors named "Tithi Biswas"

Purpose: Concurrent chemoradiation therapy is the current nonsurgical standard of care for locally advanced non-small cell lung cancer. However, this is a difficult regimen to tolerate, especially for those who are elderly, have multiple comorbidities, or have poor performance status. Alternative treatment regimens are needed for this vulnerable population.

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Small cell lung cancer (SCLC) has a propensity for brain metastases, which is associated with poor prognosis. We sought to determine predictors of overall survival (OS) and brain progression-free survival (bPFS) in SCLC patients with synchronous brain metastases at the time of initial SCLC diagnosis. A total of 107 SCLC patients with synchronous brain metastases treated at a single institution were included in this retrospective analysis.

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Introduction: Stereotactic body radiation therapy (SBRT) is an effective treatment for medically inoperable early-stage non-small cell lung cancer (NSCLC). The prognostic value of invasive nodal staging (INS) for patients undergoing SRBT has not been studied extensively. Herein, we report the impact of INS in addition to 18F-FDG-PET on treatment outcome for patients with NSCLC undergoing SBRT.

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Purpose: Stereotactic body radiation therapy (SBRT) is considered the standard of care for medically inoperable early-stage non-small cell lung cancer. There is mixed evidence on the prognostic significance of tumor metabolic activity assessed by positron emission tomography combined with computed tomography (PET/CT) using F-18 fluorodeoxyglucose (FDG). The objectives of this study were to evaluate the maximum standardized uptake value (SUV) pretreatment and at 3 and 6 months after SBRT for prediction of tumor control and survival outcomes.

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Introduction: Extensive-stage small-cell lung cancer (ES-SCLC) continues to have poor survival due to its aggressive behavior, despite improvements with incorporation of immunotherapy with standard chemotherapy. Controversy exists regarding the role of consolidative thoracic radiation therapy (TRT) and prophylactic cranial irradiation (PCI) in ES-SCLC due to high recurrence rates. We report our institutional result of the benefit of PCI and TRT in ES-SCLC.

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Purpose: The use of stereotactic body radiation therapy (SBRT) for gynecologic malignancies is controversial. We discuss certain circumstances when highly precise SBRT may be a useful tool to consider in the management of selected patients.

Methods And Materials: Case selection included the following scenarios, the first 2 with palliative intent, para-aortic nodal oligorecurrence of ovarian cancer, pelvic sidewall oligorecurrence of cervical cancer, and inoperable endometrial cancer boost after intensity modulated radiation to the pelvis treated with curative intent.

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Background: We report the results of an international multi-institutional cohort of oligometastatic (OMD) head and neck cancer (HNC) patients treated with SBRT.

Methods: Patients with OMD HNC (≤5 metastases) treated with SBRT between 2008 and 2016 at six institutions were included. Treated metastasis control (TMC), progression-free survival (PFS), and overall survival (OS) were analyzed by multivariable analysis (MVA).

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Purpose: We investigated the impact of local control (LC) on widespread progression (WSP) and overall survival (OS) in patients treated to all extracranial oligometastases (OMs) at presentation to SBRT in this retrospective review across 6 international centers.

Materials/methods: Relationships between LC status of SBRT-directed OMs and OS and WSP (>5 new active/untreated lesions) were explored using Cox and Fine-Gray regression models, adjusting for radioresistant histology and pre-SBRT systemic therapy receipt. The association between LC and dosimetric predictors was analyzed with competing risk regression using death as a competing risk and across a wide range of simulated α/βratios.

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Objectives: The potential of rideshare services to facilitate timely radiation therapy (RT), especially for resource-limited patients, is understudied.

Methods: Patients (n = 63) who received 73 courses of RT (1,513 fractions) and utilized free hospital-provided rideshare service (537 rides) were included in this retrospective study. A multidimensional analysis was conducted including a comparison of demographic, disease characteristics, and treatment completion data; a revenue analysis to evaluate the financial impact of rideshare services; and a geospatial analysis to evaluate community-level characteristics of patients.

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Introduction: It was suggested that stereotactic radiation (SBRT) is an "alternative if no surgical capacity is available" for non-small cell lung cancer (NSCLC) care during the COVID-19 pandemic. The purpose of this study was to compare the oncologic outcomes of delayed surgical resection and early SBRT among operable patients with early stage lung cancer.

Methods: The National Cancer Database was queried for patients with cT1aN0M0 NSCLC who underwent surgery or SBRT (2010-2016) with no comorbidity.

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Background: In this study, the utilization rates and survival outcomes of different radiotherapy techniques are compared in prostate cancer (PCa) patients stratified by risk group. Methods: We analyzed an extensive data set of N0, M0, non-surgical PCa patients diagnosed between 2004 and 2015 from the National Cancer Database (NCDB). Patients were grouped into six categories based on RT modality: an intensity-modulated radiation therapy (IMRT) group with brachytherapy (BT) boost, IMRT with/without IMRT boost, proton therapy, stereotactic body radiation therapy (SBRT), low-dose-rate brachytherapy (BT LDR), and high-dose-rate brachytherapy (BT HDR).

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Oligometastatic non-small cell lung cancer (NSCLC) is an intermediate state between localized and widely metastatic NSCLC, where systemic therapy in combination with aggressive local therapy when feasible can yield a favorable outcome. While different societies have adopted different definitions for oligometastatic NSCLC, the feasibility of curative intent treatment remains a major determinant of the oligometastatic state. The management involves a multidisciplinary approach to identify such patients with oligometastatic stage, including the presence of symptomatic or potentially symptomatic brain metastasis, the presence of targetable mutations, and programmed death-ligand (PD-L1) expression.

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The most common immune-related adverse events (irAEs) involve the skin, and several serve as predictors of response to immune checkpoint inhibitor (ICI) therapy, especially in melanoma. Patients with pre-existing skin autoimmune diseases (ADs) have been excluded from ICI studies for safety concerns, yet recent research has shown that dermatological ADs can be managed without discontinuing ICI therapy. Patients with ADs respond as well or better to ICIs and can be included as candidates in clinical trials.

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Breast cancer (BCa) represents a medically heterogeneous group of malignancies, with differing biological and genetic makeups [...

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Asian (AZN) women are a heterogeneous group, comprising a wide array of cultural beliefs, languages, and healthcare needs. Yet, studies of breast cancer (BCa) risks and outcomes predominately consider AZNs in aggregate, assuming that the distinct ethnicities have similar disease profiles and homogeneous responses to treatment. This stereotypical portrayal of AZNs as a homogenous group tends to mask disparities.

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Accurate coregistration of computed tomography (CT) and magnetic resonance (MR) imaging can provide clinically relevant and complementary information and can serve to facilitate multiple clinical tasks including surgical and radiation treatment planning, and generating a virtual Positron Emission Tomography (PET)/MR for the sites that do not have a PET/MR system available. Despite the long-standing interest in multimodality co-registration, a robust, routine clinical solution remains an unmet need. Part of the challenge may be the use of mutual information (MI) maximization and local phase difference (LPD) as similarity metrics, which have limited robustness, efficiency, and are difficult to optimize.

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Purpose: Prolonged survivorship is increasingly observed in patients with oligometastases (OM) treated with stereotactic body radiation therapy (SBRT). The purpose of this study was to study the conditional survival of patients with OM, which can provide more detailed prognostic information over time by considering time already survived.

Methods And Materials: A multi-institutional database consisting of 1033 patients with OM (≤5 metastases) treated with SBRT between 2006 and 2017 was analyzed.

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Purpose: Stereotactic body radiation therapy (SBRT) has become the standard of care for medically inoperable early-stage non-small cell lung cancer. We investigated 2 modalities of lung SBRT, CyberKnife (CK) and volumetric modulated arc therapy (VMAT), for differences in dosimetric parameters, tumor control, and clinical outcomes.

Methods And Materials: Patients who underwent SBRT for T1-2N0M0 non-small cell lung cancer from 2012 to 2018 were included.

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Purpose: In recent years, stereotactic body radiotherapy (SBRT) has emerged as an effective treatment for oligometastatic cancers. Here, we report radiation treatment parameters and clinical outcomes for patients with oligometastatic colorectal cancer (CRC) treated with SBRT using a large multi-institutional database.

Methods: Patients with extra-cranial oligometastatic CRC (≤5 lesions) treated with SBRT at six large academic cancer centers were included.

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Purpose: Patients with oligometastatic disease (OMD) can experience durable disease control with ablative therapy to all sites of disease. Stereotactic body radiation therapy (SBRT) is an important modality in the management of OMD, although a validated prognostic model for OMD treated with SBRT is currently lacking. The purpose of this study was to develop a prognostic model for overall survival (OS) in patients with OMD treated with SBRT.

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Background: Neutrophil-to-lymphocyte ratio (NLR) is an important pretreatment marker of systemic inflammation and tumor aggressiveness. Increased levels of this ratio have been associated with reduced survival in several observational studies of lung cancer. However, supporting analyses from large clinical trial data are lacking.

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Purpose: TRC102, a small-molecule base-excision repair inhibitor, potentiates the cytotoxicity of pemetrexed and reverses resistance by binding to chemotherapy-induced abasic sites in DNA. We conducted a phase I clinical trial combining pemetrexed and TRC102 with cisplatin-radiation in stage III nonsquamous non-small cell lung cancer (NS-NSCLC).

Patients And Methods: Fifteen patients were enrolled from 2015 to 2019.

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Background: We hypothesized that the total volume of metastases at initial oligometastatic (OM) presentation to stereotactic body radiation therapy (SBRT) is an important prognostic factor that can refine the definition of OM disease.

Methods: Patients with extracranial oligometastatic cancer (≤5 lesions) treated with SBRT were included in an international multi-institutional database. Multivariable Cox and competing risks regression models were used to determine the relationship between distant progression-free survival (DPFS), widespread progression (WSP), and overall survival (OS) with the total planning target volume (PTV) at initial OM presentation to SBRT.

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Purpose/objectives: Outcomes of T2N0 lung cancer patients treated with stereotactic radiotherapy are not well known.

Methods And Materials: We conducted a single institution retrospective review of patients with T2N0 NSCLC who were treated with SBRT. The local, regional, distant control rates were calculated from available clinical data.

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