Nearly all women who receive radiotherapy (RT) for breast cancer experience some degree of radiation dermatitis. However, evidence describing the appropriate management of radiation dermatitis is ...often lacking or contradictory. Here, we summarize the available literature regarding radiation dermatitis causes, the presentation and timing of symptoms, methods for dermatitis assessment and prevention, and review evidence-based management strategies.
Decisions to continue or suspend therapy with immune checkpoint inhibitors are commonly guided by tumor dynamics seen on serial imaging. However, immunotherapy responses are uniquely challenging to ...interpret because tumors often shrink slowly or can appear transiently enlarged due to inflammation. We hypothesized that monitoring tumor cell death in real time by quantifying changes in circulating tumor DNA (ctDNA) levels could enable early assessment of immunotherapy efficacy.
We compared longitudinal changes in ctDNA levels with changes in radiographic tumor size and with survival outcomes in 28 patients with metastatic non-small cell lung cancer (NSCLC) receiving immune checkpoint inhibitor therapy. CtDNA was quantified by determining the allele fraction of cancer-associated somatic mutations in plasma using a multigene next-generation sequencing assay. We defined a ctDNA response as a >50% decrease in mutant allele fraction from baseline, with a second confirmatory measurement.
Strong agreement was observed between ctDNA response and radiographic response (Cohen's kappa, 0.753). Median time to initial response among patients who achieved responses in both categories was 24.5 days by ctDNA versus 72.5 days by imaging. Time on treatment was significantly longer for ctDNA responders versus nonresponders (median, 205.5 vs. 69 days;
< 0.001). A ctDNA response was associated with superior progression-free survival hazard ratio (HR), 0.29; 95% CI, 0.09-0.89;
= 0.03, and superior overall survival (HR, 0.17; 95% CI, 0.05-0.62;
= 0.007).
A drop in ctDNA level is an early marker of therapeutic efficacy and predicts prolonged survival in patients treated with immune checkpoint inhibitors for NSCLC.
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The execution of apoptosis is critical for proper development of the nervous system. However, it is equally important that neurons strictly inhibit apoptosis after development to ensure their ...survival throughout the lifetime of the organism. Here we show that a microRNA, miR-29b, is markedly induced with neuronal maturation and functions as a novel inhibitor of neuronal apoptosis. The prosurvival function of miR-29b is mediated by targeting genes in the proapoptotic BH3-only family. Our results identify a unique strategy evolved by maturing neurons that uses a single microRNA to inhibit the multiple, redundant BH3-only proteins that are key initiators of apoptosis.
The androgen receptor (AR) is required for male sex development and contributes to prostate cancer cell survival. In contrast to other nuclear receptors that bind the L
XXLL motifs of coactivators, ...the AR ligand binding domain is preferentially engaged in an interdomain interaction with the AR F
XXLF motif. Reported here are crystal structures of the ligand-activated AR ligand binding domain with and without bound F
XXLF and L
XXLL peptides. Key residues that establish motif binding specificity are identified through comparative structure-function and mutagenesis studies. A mechanism in prostate cancer is suggested by a functional AR mutation at a specificity-determining residue that recovers coactivator L
XXLL motif binding. An activation function transition hypothesis is proposed in which an evolutionary decline in L
XXLL motif binding parallels expansion and functional dominance of the NH
2-terminal transactivation domain in the steroid receptor subfamily.
Invasive ductal carcinoma (IDC) often presents alone or with a co-existing ductal carcinoma in situ component (IDC + DCIS). Studies have suggested that pure IDC may exhibit different biological ...behavior than IDC + DCIS, but whether this translates to a difference in outcomes is unclear. Here, utilizing the National Cancer Database we identified 494,801 stage I-III breast cancer patients diagnosed with either IDC alone or IDC + DCIS. We found that IDC + DCIS was associated with significantly better overall survival (OS) compared to IDC alone (5-year OS, 89.3% vs. 85.5%, p < 0.001), and this finding persisted on multivariable Cox modeling adjusting for demographic, clinical, and treatment-related variables. The significantly superior OS observed for IDC + DCIS was limited to patients with invasive tumor size < 4 cm or with node negative disease. A greater improvement in OS was observed for tumors containing ≥25% DCIS component. We also found IDC + DCIS to be associated with lower T/N stage, low/intermediate grade, ER/PR positivity, and receipt of mastectomy. Thus, the presence of a DCIS component in patients with IDC is associated with favorable clinical characteristics and independently predicts improved OS. IDC + DCIS could be a useful prognostic factor for patients with breast cancer, particularly if treatment de-escalation is being considered for small or node negative tumors.
The ability to withstand mitochondrial damage is especially critical for the survival of postmitotic cells, such as neurons. Likewise, cancer cells can also survive mitochondrial stress. We found ...that cytochrome c (Cyt c), which induces apoptosis upon its release from damaged mitochondria, is targeted for proteasome-mediated degradation in mouse neurons, cardiomyocytes, and myotubes and in human glioma and neuroblastoma cells, but not in proliferating human fibroblasts. In mouse neurons, apoptotic protease-activating factor 1 (Apaf-1) prevented the proteasome-dependent degradation of Cyt c in response to induced mitochondrial stress. An RNA interference screen in U-87 MG glioma cells identified p53-associated Parkin-like cytoplasmic protein (PARC, also known as CUL9) as an E3 ligase that targets Cyt c for degradation. The abundance of PARC positively correlated with differentiation in mouse neurons, and overexpression of PARC reduced the abundance of mitochondrially-released cytosolic Cyt c in various cancer cell lines and in mouse embryonic fibroblasts. Conversely, neurons from Parc-deficient mice had increased sensitivity to mitochondrial damage, and neuroblastoma or glioma cells in which PARC or ubiquitin was knocked down had increased abundance of mitochondrially-released cytosolic Cyt c and decreased viability in response to stress. These findings suggest that PARC-mediated ubiquitination and degradation of Cyt c is a strategy engaged by both neurons and cancer cells to prevent apoptosis during conditions of mitochondrial stress.
Optimal treatment of nonoperative patients with large, node-negative non-small cell lung cancer (NSCLC) is poorly defined. Current NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) ...recommend definitive radiotherapy (RT) with or without sequential chemotherapy and do not include concurrent chemoradiotherapy (chemoRT) as a treatment option. In this study, we identified factors that predict nonadherence to NCCN Guidelines.
Patients who received definitive RT for nonmetastatic, node-negative NSCLC with tumor size of 5 to 7 cm were identified in the National Cancer Database from 2004 through 2016. Patients were evaluated by RT type (stereotactic body RT SBRT, hypofractionated RT HFRT, or conventionally fractionated RT CFRT) and chemotherapy use (none, sequential, or concurrent with RT). Patients were classified as receiving NCCN-adherent (RT with or without sequential chemotherapy) or NCCN-nonadherent (concurrent chemoRT) treatment. Demographic and clinical factors were assessed with logistic regression modeling. Overall survival was evaluated with Kaplan-Meier, log-rank, and univariable/multivariable Cox proportional hazards regression analyses.
Among 2,020 patients in our cohort, 32% received NCCN-nonadherent concurrent chemoRT, whereas others received NCCN-adherent RT alone (51%) or sequential RT and chemotherapy (17%). CFRT was most widely used (64% CFRT vs 22% SBRT vs 14% HFRT). Multivariable analysis revealed multiple factors to be associated with NCCN-nonadherent chemoRT: age ≤70 versus >70 years (odds ratio OR , 2.72; P<.001), treatment at a nonacademic facility (OR, 1.65; P<.001), and tumor size 6 to 7 cm versus 5 to 6 cm (OR, 1.27; P=.026). Survival was similar between the NCCN-nonadherent chemoRT and NCCN-adherent groups (hazard ratio, 1.00; P=.992) in multivariable analysis.
A substantial proportion of inoperable patients with large, node-negative NSCLC are not treated according to NCCN Guidelines and receive concurrent chemoRT. Younger patients with larger tumors receiving treatment at nonacademic medical centers were more likely to receive NCCN-nonadherent therapy, but adherence to NCCN Guidelines was not associated with differences in overall survival.
•Little is known about optimal treatments and patterns of failure for non-operative patients with large, node-negative non–small cell lung cancer as this group is commonly excluded from major ...prospective clinical trials.•Patients treated with definitive radiation therapy have high rates of both regional and distant progression.•Systemic chemotherapy use is associated with significant reductions in the risk of regional and distant failure.•Ablative radiotherapy (i.e., stereotactic body radiotherapy, or SBRT) is associated with the highest rates of local control.•For inoperable patients in this cohort, strong consideration should be made to treat with SBRT and adjuvant systemic therapy when feasible.
The ideal non-operative treatment for patients with large, node-negative non–small cell lung cancer (NSCLC) is poorly defined. To inform optimal treatment paradigms for this cohort, we examined patterns of failure and the impact of radiation therapy (RT) and chemotherapy receipt.
Node-negative NSCLC patients with 5+ cm primary tumors receiving definitive RT at our institution were identified. Sites of initial progression were analyzed. Local progression, regional/distant progression, progression-free survival, and overall survival were analyzed via cumulative incidence function and Kaplan-Meier. Associations between local vs. regional/distant progression with treatment and clinicopathologic variables were assessed via univariable and multivariable competing risks regression.
We identified 88 patients for analysis. Among patients with recurrent disease (N = 36), initial patterns of failure analysis showed that isolated distant (27.8%) and isolated regional progression (22.2%) were most common. Distant or regional failure as a component of initial failure was seen in 88.9% of patients who progressed, while isolated local failure was uncommon (11.1%). Univariable and multivariable competing risks regression showed that receipt of SBRT was associated with reduced risk of local progression (HR 0.23, P = .012), and receipt of chemotherapy was associated with reduced risk of regional/distant progression (HR 0.12, P = .040). In conclusion, patients with large, node-negative NSCLC treated with definitive RT are at high risk of regional and distant progression. SBRT correlates with a reduced risk of local failure while chemotherapy is associated with reduced regional/distant progression in this patient population. Ideal treatment may include SBRT when feasible with appropriate systemic therapy.
Patterns of failure were examined in 88 non-operative patients with 5+cm, N0 NSCLC. Regional and/or distant progression was the dominant failure mode and was significantly reduced in patients receiving systemic therapy. Local failure was less common and was significantly reduced with receipt of SBRT. The optimal treatment paradigm for this population of patients may be SBRT followed by systemic therapy.
Currently, there is insufficient guidance for standard fractionation lung planning using the Varian Ethos adaptive treatment planning system and its unique intelligent optimization engine. Here, we ...address this gap in knowledge by developing a methodology to automatically generate high-quality Ethos treatment plans for locally advanced lung cancer.
Fifty patients previously treated with manually generated Eclipse plans for inoperable stage IIIA-IIIC non-small cell lung cancer were included in this institutional review board–approved retrospective study. Fifteen patient plans were used to iteratively optimize a planning template for the Daily Adaptive vs Non-Adaptive External Beam Radiation Therapy With Concurrent Chemotherapy for Locally Advanced Non-Small Cell Lung Cancer: A Prospective Randomized Trial of an Individualized Approach for Toxicity Reduction (ARTIA-Lung); the remaining 35 patients were automatically replanned without intervention. Ethos plan quality was benchmarked against clinical plans and reoptimized knowledge-based RapidPlan (RP) plans, then judged using standard dose-volume histogram metrics, adherence to clinical trial objectives, and qualitative review.
Given equal prescription target coverage, Ethos-generated plans showed improved primary and nodal planning target volume V95% coverage (P < .001) and reduced lung gross tumor volume V5 Gy and esophagus D0.03 cc metrics (P ≤ .003) but increased mean esophagus and brachial plexus D0.03 cc metrics (P < .001) compared with RP plans. Eighty percent, 49%, and 51% of Ethos, clinical, and RP plans, respectively, were “per protocol” or met “variation acceptable” ARTIA-Lung planning metrics. Three radiation oncologists qualitatively scored Ethos plans, and 78% of plans were clinically acceptable to all reviewing physicians, with no plans receiving scores requiring major changes.
A standard Ethos template produced lung radiation therapy plans with similar quality to RP plans, elucidating a viable approach for automated plan generation in the Ethos adaptive workspace.
Because proton beam therapy (PBT) can lower the dose of radiation to the heart, lungs, and breast, it is an established radiation modality for patients with Hodgkin lymphoma (HL). Pencil beam ...scanning (PBS) PBT facilitates the treatment of more extensive targets. This may be especially of value for lymphoma patients who require RT to both mediastinal and axillary targets, defined here as extended target RT (ETRT), given the target distribution and need to minimize the lung, heart, and breast dose. Using the Proton Collaborative Group registry, we identified patients with HL treated with PBT to both their mediastinum and axilla, for which DICOM-RT was available. All patients were treated with PBS. To evaluate the dosimetric impact of PBS, we compared delivered PBS plans with VMAT butterfly photon plans optimized to have the same target volume coverage, when feasible. Between 2016 and 2021, twelve patients (median 26 years) received PBS ETRT (median 30.6 Gy (RBE)). Despite the large superior/inferior (SI, median 22.2 cm) and left/right (LR, median 22.8 cm) extent of the ETRT targets, all patients were treated with one isocenter except for two patients (both with SI and LR > 30 cm). Most commonly, anterior beams, with or without posterior beams, were used. Compared to photons, PBS had greater target coverage, better conformity, and lower dose heterogeneity while achieving lower doses to the lungs and heart, but not to the breast. No acute grade 3+ toxicities were reported, including pneumonitis. Proton ETRT in this small cohort was safely delivered with PBS and was associated with an improved sparing of the heart and lungs compared to VMAT.
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