Palliative care utilization and racial and ethnic disparities among women with de novo metastatic breast cancer in the United States.

PURPOSE: The potential disparities in palliative care delivery for underrepresented minorities with breast cancer are not well known. We sought to determine whether race and ethnicity impact the receipt of palliative care for patients with metastatic breast cancer (MBC). METHODS: We retrospectively reviewed the National Cancer Database for female patients diagnosed with stage IV breast cancer between 2010 and 2017 who received palliative care following diagnosis of MBC to assess the proportion of patients who received palliative care, including non-curative-intent local-regional or systemic therapy. Multivariable logistic regression analysis was performed to identify variables associated with receiving palliative care. RESULTS: 60,685 patients were diagnosed with de novo MBC. Of these, only 21.4% (n = 12,963) received a palliative care service. Overall, there was a positive trend in palliative care receipt from 18.2% in 2010 to 23.0% in 2017 (P < 0.001), which persisted when stratified by race and ethnicity. Relative to non-Hispanic White women, Asian/Pacific Islander women (aOR 0.80, 95% CI 0.71-0.90, P < 0.001), Hispanic women (adjusted odds ratio [aOR] 0.69, 95% CI 0.63-0.76, P < 0.001), and non-Hispanic Black women (aOR 0.94, 95% CI 0.88-0.99, P = 0.03) were less likely to receive palliative care. CONCLUSIONS: Fewer than 25% of women with MBC received palliative care between 2010 and 2017. While palliative care has significantly increased for all racial/ethnic groups, Hispanic White, Black, and Asian/Pacific Islander women with MBC still receive significantly less palliative care than non-Hispanic White women. Further research is needed to identify the socioeconomic and cultural barriers to palliative care utilization.

Florida-California Cancer Research, Education and Engagement (CaRE2) Health Equity Center: Structure, Innovations, and Initial Outcomes.

INTRODUCTION: The Florida-California Cancer Research, Education, and Engagement (CaRE2) Health Equity Center is a triad partnership committed to increasing institutional capacity for cancer disparity research, the diversity of the cancer workforce, and community empowerment. This article provides an overview of the structure, process innovations, and initial outcomes from the first 4 years of the CaRE2 triad partnership. METHODS: CaRE2 serves diverse populations in Florida and California using a "molecule to the community and back" model. We prioritize research on the complex intersection of biological, environmental, and social determinants health, working together with scientific and health disparities communities, sharing expertise across institutions, bidirectional training, and community outreach. Partnership progress and outcomes were assessed using mixed methods and four Program Steering Committee meetings. RESULTS: Research capacity was increased through development of a Living Repository of 81 cancer model systems from minority patients for novel cancer drug development. CaRE2 funded 15 scientific projects resulting in 38 publications. Workforce diversity entailed supporting 94 cancer trainees (92 URM) and 34 ESIs (32 URM) who coauthored 313 CaRE2-related publications and received 48 grants. Community empowerment was promoted via outreaching to more than 3000 individuals, training 145 community cancer advocates (including 28 Community Scientist Advocates), and publishing 10 community reports. CaRE2 members and trainees together have published 639 articles, received 61 grants, and 57 awards. CONCLUSION: The CaRE2 partnership has achieved its initial aims. Infrastructure for translational cancer research was expanded at one partner institution, and cancer disparities research was expanded at the two cancer centers.

Frailty and risk of mortality in older cancer survivors and adults without a cancer history: Evidence from the National Health and Nutrition Examination Survey, 1999-2014.

BACKGROUND: Epidemiologic evidence reporting the role of frailty in survival among older adults with a prior cancer diagnosis is limited. METHODS: A total of 2050 older adults (≥60 years old) surviving for at least 1 year after a cancer diagnosis and 9474 older adults without a cancer history from the National Health and Nutrition Examination Survey (1999-2014) were included for analysis. The exposure variable, a 45-item frailty index (FI), was categorized on the basis of validated cutoffs (FI ≤ 0.10 [fit], 0.10 < FI ≤ 0.21 [prefrail], and FI > 0.21 [frail]). All-cause mortality was ascertained via the National Death Index. Multivariable Cox proportional hazards models were used to estimate adjusted hazard ratios (aHRs) and 95% confidence interval (CIs) for the FI, and this was followed by restricted cubic splines depicting dose-response curves. RESULTS: For older cancer survivors, the mean age at the baseline was 72.6 years (SD, 7.1 years); 5.9% were fit, 38.2% were prefrail, and 55.9% were frail. Older adults without a cancer history were slightly younger (mean age, 70.0 years) and less frail (47.9% were frail). At each level of the FI, cancer survivors (1.9 per 100 person-years for FI ≤ 0.10, 3.4 per 100 person-years for 0.10 < FI ≤ 0.21, and 7.5 per 100 person-years for FI > 0.21) had higher mortality than their cancer-free counterparts (1.4 per 100 person-years for FI ≤ 0.10, 2.4 per 100 person-years for 0.10 < FI ≤ 0.21, and 5.4 per 100 person-years for FI > 0.21). The multivariable model suggested a positive association between the FI and all-cause mortality for survivors (aHR for FI > 0.21 vs FI ≤ 0.10, 2.80; 95% CI, 1.73-4.53) and participants without a cancer history (aHR for FI > 0.21 vs FI ≤ 0.10, 2.75; 95% CI, 2.29-3.32). Restricted cubic splines indicated that all-cause mortality risk increased with the FI in a monotonic pattern. CONCLUSIONS: Frailty is associated with a higher risk of death in older cancer survivors and the elderly without a cancer history.

Intraoperative radiation therapy for early-stage breast cancer: a single-institution experience.

Background: To assess outcomes and toxicity after low-energy intraoperative radiotherapy (IORT) for early-stage breast cancer (ESBC). Materials and methods: We reviewed patients with unilateral ESBC treated with breast-conserving surgery and 50-kV IORT at our institution. Patients were prescribed 20 Gy to the surface of the spherical applicator, fitted to the surgical cavity during surgery. Patients who did not meet institutional guidelines for IORT alone on final pathology were recommended adjuvant treatment, including additional surgery and/or external-beam radiation therapy (EBRT). We analyzed ipsilateral breast tumor recurrence, overall survival, recurrence-free survival and toxicity. Results: Among 201 patients (median follow-up, 5.1 years; median age, 67 years), 88% were Her2 negative and ER positive and/or PR positive, 98% had invasive ductal carcinoma, 87% had grade 1 or 2, and 95% had clinical T1 disease. Most had pathological stage T1 (93%) N0 (95%) disease. Mean IORT applicator dose at 1-cm depth was 6.3 Gy. Post-IORT treatment included additional surgery, 10%; EBRT, 11%; adjuvant chemotherapy, 9%; and adjuvant hormonal therapy, 74%. Median total EBRT dose was 42.4 (range, 40.05-63) Gy and median dose per fraction was 2.65 Gy. At 5 years, the cumulative incidence of ipsilateral breast tumor recurrence was 2.7%, the overall survival rate was 95% with no breast cancer-related deaths, and the recurrence-free survival rate was 96%. For patients who were deemed unsuitable for postoperative IORT alone and did not receive recommended risk-adapted EBRT, the IBTR rate was 4.7% versus 1.7% (p = 0.23) for patients who were either suitable for IORT alone or unsuitable and received adjuvant EBRT. Cosmetic toxicity data was available for 83%, with 7% experiencing grade 3 breast toxicity and no grade 4-5 toxicity. Conclusions: IORT for select patients with ESBC results in acceptable outcomes in regard to ipsilateral breast tumor recurrence and toxicity.

Five-Year Breast Surgeon Experience in LYMPHA at Time of ALND for Treatment of Clinical T1-4N1-3M0 Breast Cancer.

BACKGROUND: Breast cancer-related lymphedema (BCRL) is a source of postoperative morbidity for breast cancer survivors. Lymphatic microsurgical preventive healing approach (LYMPHA) is a technique used to prevent BCRL at the time of axillary lymph node dissection (ALND). We report the 5-year experience of a breast surgeon trained in LYMPHA and investigate the outcomes of patients who underwent LYMPHA following ALND for treatment of cT1-4N1-3M0 breast cancer. METHODS: A retrospective review of patients with cT1-4N1-3M0 breast cancer was performed in patients who underwent ALND with and without LYMPHA. Diagnosis of BCRL was made by certified lymphedema therapists. Descriptive statistics and lymphedema surveillance data were analyzed using results of Fisher's exact or Wilcoxon rank-sum tests. Logistic regression and propensity matching were performed to assess the reduction of BCRL occurrence following LYMPHA. RESULTS: In a 5-year period, 132 patients met inclusion criteria with 76 patients undergoing LYMPHA at the time of ALND and 56 patients undergoing ALND alone. Patients who underwent LYMPHA at the time of ALND were significantly less likely to develop BCRL than those who underwent ALND alone (p = 0.045). Risk factors associated with BCRL development were increased patient age (p = 0.007), body mass index (BMI) (p = 0.003), and, in patients undergoing LYMPHA, number of positive nodes (p = 0.026). CONCLUSIONS: LYMPHA may be successfully employed by breast surgeons trained in lymphatic-venous anastomosis at the time of ALND. While research efforts should continue to focus on prevention and surveillance of BCRL, LYMPHA remains an option to reduce BCRL and improve patient quality of life.

An Amino Acid-Based Oral Rehydration Solution Regulates Radiation-Induced Intestinal Barrier Disruption in Mice.

BACKGROUND: Radiotherapy inadvertently affects gastrointestinal (GI) epithelial cells, causing intestinal barrier disruption and increased permeability. OBJECTIVE: We examined the effect of amino acid-based oral rehydration solution (AA-ORS) on radiation-induced changes of intestinal barrier function and epithelial tight junctions (TJs) in a randomized experimental study using a total-body irradiation (TBI) mouse model. METHODS: Eight-week-old male Swiss mice received a single-dose TBI (0, 1, 3, or 5 Gy), and subsequent gastric gavage with AA-ORS (threonine, valine, serine, tyrosine, and aspartic acid) or saline for 2 or 6 d. Intestinal barrier function of mouse ileum was characterized by electrophysiological analysis of conductance, anion selectivity, and paracellular permeability [fluorescein isothiocyanate (FITC)-dextran]. Ultrastructural changes of TJs were evaluated by transmission electron microscopy. Membrane protein and mRNA expression of claudin-1, -2, -3, -5, and -7, occludin, and E-cadherin were analyzed with western blot, qPCR, and immunohistochemistry. Nonparametric tests were used to compare treatment-dose differences for each time point. RESULTS: Saline-treated mice had a higher conductance at doses as low as 3 Gy, and as early as 2 d post-TBI compared with 0 Gy (P < 0.001). Paracellular permeability and dilution potential were increased 6 d after 5 Gy TBI (P < 0.001). Conductance decreased with AA-ORS after 2 d in 3-Gy and 5-Gy mice (P < 0.05 and P < 0.001), and on day 6 after 5 Gy TBI (P < 0.001). Anion selectivity and FITC permeability decreased from 0.73 ± 0.02 to 0.61 ± 0.03 pCl/pNa (P < 0.01) and from 2.7 ± 0.1 × 105 to 2.1 ± 0.1 × 105 RFU (P < 0.001) in 5-Gy mice treated with AA-ORS for 6 d compared with saline. Irradiation-induced ultrastructural changes of TJs characterized by decreased electron density and gap formation improved with AA-ORS. Reduced claudin-1, -3, and -7 membrane expression after TBI recovered with AA-ORS within 6 d, whereas claudin-2 decreased indicating restitution of TJ proteins. CONCLUSIONS: Radiation-induced functional and structural disruption of the intestinal barrier in mice is reversed by AA-ORS rendering AA-ORS a potential treatment option in prospective clinical trials in patients with gastrointestinal barrier dysfunction.

Projected clinical benefit of surveillance imaging for early detection and treatment of breast cancer metastases.

This article presents current best knowledge to assess the projected outcomes benefit of adding multi-modality surveillance imaging to standard follow-up care for breast cancer patients at high risk (>30%) for developing future metastases. This analysis is motivated by recent preliminary clinical studies that have suggested that augmenting systemic treatment of early-stage metastases with targeted surgery and/or radiosurgery achieves significant overall survival and disease-free survival benefit. Our primary aims are to: (a) describe the clinical motivation and scan parameters needed to identify the early onset of metastatic progression in breast cancer patients for effective surgical or radiosurgical treatment; (b) estimate the anticipated survival benefit for high-risk patients under this recommended protocol; and (c) estimate the radiation risks associated with the repeated body imaging of this protocol.

Stereotactic Ablative Body Radiotherapy for Primary Non-Small-Cell Lung Cancer: Achieving Local Control with a Lower Biologically Effective Dose.

We conducted a retrospective study of stereotactic ablative radiotherapy (SABR) for 94 patients with non-small-cell lung cancer at our institution. The patients were treated with either 50 Gy in five treatments or 48 Gy in four treatments, corresponding to biologically effective doses (BED) of 100 Gy or 105.6 Gy, respectively. The results demonstrate that, with relatively low BEDs, we can achieve excellent local control with minimal toxicity.

Glucose enhances rotavirus enterotoxin-induced intestinal chloride secretion.

Rotavirus causes severe diarrhea in small children and is typically treated using glucose-containing oral rehydration solutions; however, glucose may have a detrimental impact on these patients, because it increases chloride secretion and presumably water loss. The rotavirus enterotoxin nonstructural protein 4 (NSP4) directly inhibits glucose-mediated sodium absorption. We examined the effects of NSP4 and glucose on sodium and chloride transport in mouse small intestines and Caco-2 cells. Mouse small intestines and Caco-2 cells were incubated with NSP4114-135 in the presence/absence of glucose. Absorption and secretion of sodium and chloride, fluid movement, peak amplitude of intracellular calcium fluorescence, and expression of Ano1 and sodium-glucose cotransporter 1 were assessed. NHE3 activity increased, and chloride secretory activity decreased with age. Net chloride secretion increased, and net sodium absorption decreased in the intestines of 3-week-old mice compared to 8-week-old mice with NSP4. Glucose increased NSP4-stimulated chloride secretion. Glucose increased NSP4-stimulated increase in short-circuit current measurements (I sc) and net chloride secretion. Ano1 cells with siRNA knockdown showed a significant difference in I sc in the presence of NSP4 and glucose without a significant difference in peak calcium fluorescence intracellular when compared to non-silencing (N.S.) cells. The failure of glucose to stimulate significant sodium absorption was likely due to the inhibition of sodium-hydrogen exchange and sodium-glucose cotransport by NSP4. Since glucose enhances intestinal chloride secretion and fails to increase sodium absorption in the presence of NSP4, glucose-based oral rehydration solutions may not be ideal for the management of rotaviral diarrhea.

Amino Acid Hydration Decreases Radiation-Induced Nausea in Mice: A Pica Model.

Nausea and diarrhea are common yet inconsistent side effects of abdominal and pelvic irradiation. Their frequency, chronicity, and severity vary greatly, and the reasons for inter-subject variability are unknown. We studied the potential for radiation-induced changes in amino acid absorption and mucosal barrier function to lead to gastrointestinal toxicity. We found profound and prolonged changes in the absorption and secretion of several electrolytes and nutrients, caused by changes in transporter function, after radiation doses as low as 1 to 3 Gy. After identifying absorbed and non-absorbed amino acids, we demonstrated the role of a beneficial amino acid drink to alleviate radiation-related gastrointestinal symptoms in a mouse model.

Synthesis and anticancer potential of novel xanthone derivatives with 3,6-substituted chains.

In an effort to develop new drug candidates with enhanced anticancer activity, our team synthesized and assessed the cytotoxicity of a series of novel xanthone derivatives with two longer 3,6-disubstituted amine carbonyl methoxy side chains on either benzene ring in selected human cancer cell lines. An MTT assay revealed that a set of compounds with lower IC50 values than the positive control, 5-FU, exhibited greater anticancer effects. The most potent derivative (XD8) exhibited anticancer activity in MDA-MB-231, PC-3, A549, AsPC-1, and HCT116 cells lines with IC50 values of 8.06, 6.18, 4.59, 4.76, and 6.09µM, respectively. Cell cycle analysis and apoptosis activation suggested that the mechanism of action of these derivatives includes cell cycle regulation and apoptosis induction.

Brain metastasis from melanoma: the prognostic value of varying sites of extracranial disease.

Patients with brain metastasis from melanoma have poor outcomes. Radiation is used both for prognostic and symptomatic value. We aimed to further clarify the role of stereotactic radiosurgery (SRS) and whole brain radiotherapy (WBRT) as well as the prognostic implication of various sites of extracranial disease. The records of 73 consecutive patients treated at the University of Rochester Medical Center for brain-metastatic melanoma from January 2004 to October 2013 were reviewed. The median overall survival (OS) was 3.0 months. Patients treated with WBRT alone had decreased OS compared to those treated with SRS alone (HR = 0.38, p = 0.001) or WBRT and SRS (HR = 0.51, p = 0.039). The mean number of brain metastasis differed (p = 0.002) in patients in patients who received WBRT (4.0) compared to those who did not (2.0). Among patients with extracranial disease (n = 63), bone metastasis (HR = 1.86, p = 0.047, n = 15) was a negative prognostic factor; liver (HR = 1.59, p = 0.113, n = 17), lung (HR = 1.51, p = 0.23, n = 51) and adrenal metastasis (HR = 1.70, p = 0.15, n = 10) were not. In patients with concurrent brain and lung metastasis, those with disease limited to those two sites (OS = 8.7 mo, n = 13) had improved OS (HR = 0.44, p = 0.014) compared to those with additional disease (OS = 1.8 mo, n = 50). Based on this hypothesis-generating retrospective analysis, SRS may offer survival benefit compared to WBRT alone in patients with brain metastatic melanoma. Bone metastasis appears to confer a particularly poor prognosis. Those with disease confined to the lung and brain may represent a population with improved prognosis.

Glucose stimulates calcium-activated chloride secretion in small intestinal cells.

The sodium-coupled glucose transporter-1 (SGLT1)-based oral rehydration solution (ORS) used in the management of acute diarrhea does not substantially reduce stool output, despite the fact that glucose stimulates the absorption of sodium and water. To explain this phenomenon, we investigated the possibility that glucose might also stimulate anion secretion. Transepithelial electrical measurements and isotope flux measurements in Ussing chambers were used to study the effect of glucose on active chloride and fluid secretion in mouse small intestinal cells and human Caco-2 cells. Confocal fluorescence laser microscopy and immunohistochemistry measured intracellular changes in calcium, sodium-glucose linked transporter, and calcium-activated chloride channel (anoctamin 1) expression. In addition to enhancing active sodium absorption, glucose increased intracellular calcium and stimulated electrogenic chloride secretion. Calcium imaging studies showed increased intracellular calcium when intestinal cells were exposed to glucose. Niflumic acid, but not glibenclamide, inhibited glucose-stimulated chloride secretion in mouse small intestines and in Caco-2 cells. Glucose-stimulated chloride secretion was not seen in ileal tissues incubated with the intracellular calcium chelater BAPTA-AM and the sodium-potassium-2 chloride cotransporter 1 (NKCC1) blocker bumetanide. These observations establish that glucose not only stimulates active Na absorption, a well-established phenomenon, but also induces a Ca-activated chloride secretion. This may explain the failure of glucose-based ORS to markedly reduce stool output in acute diarrhea. These results have immediate potential to improve the treatment outcomes for acute and/or chronic diarrheal diseases by replacing glucose with compounds that do not stimulate chloride secretion.

Mitochondrial genetic abnormalities after radiation exposure.

Because mitochondria are prone to oxidative stress, damage to their DNA might provide a record of radiation exposure. We measured the effect of gamma radiation on mitochondrial DNA (mtDNA) copy number and common deletion (mito-CD) mutations using Beas-2B and HFL-1 cells lines and C3H/HeJ mice exposed to total-body irradiation (TBI) and sub-TBI. DNA was extracted 5 days after cell irradiation or 12 months after animal exposure. We found that: (1) natural ratios of mtDNA/nDNA and mito-CD/mtDNA varied between cell lines; (2) mtDNA copy number decreased in Beas-2B and increased in HFL-1 following 2 Gy; (3) mito-CD in both cell lines increased after 2 Gy; (4) in aged mice, the natural ratios of mtDNA/nDNA varied from 0.723 to 8.146 in different tissues; (5) in kidney tissue, TBI and sub-TBI mildly increased mtDNA copy number but substantially increased mtDNA-CD; and (6) in liver tissue, TBI and sub-TBI induced a slight increase in mtDNA copy number and a larger increase in mtDNA-CD. These findings indicate that mtDNA copy number varies in time by cell type, but there is a substantial and sustained increase in mtDNA mutations that occurs to different degrees in different tissues and cells following irradiation.

A new flavonoid regulates angiogenesis and reactive oxygen species production.

The tumor vascular system, which is critical to the survival and growth of solid tumors, has been an attractive target for anticancer research. Building on studies that show that some flavonoids have anticancer vascular effects, we developed and analyzed the flavonoid derivative R24 [3, 6-bis (2-oxiranylmethoxy)-9H-xanthen-9-one]. A CAM assay revealed that R24 disrupted neovascular formation; fewer dendrites were detected and overall dendritic length was shorter in the R24-treated chicken embryos. The antiproliferative effect of R24 was measured by MTT assay in A549 (lung cancer), AsPC-1 (pancreatic cancer), HCT-116 (colorectal cancer), and PC-3 (prostate cancer) cell lines. R24 reduced proliferation with an IC50 of 3.44, 3.59, 1.22, and 11.83 µM, respectively. Cell-cycle analysis and Annexin-V/propidium iodide staining showed that R24 induced apoptosis. In addition, R24 regulated intracellular ROS production in a dose-dependent manner. CM-H2DCFDA staining indicated that intracellular ROS production increased with the R24 dose. In summary, we found that R24 exhibits potent antiangiogenic and antiproliferative effects, induces apoptosis, and promotes ROS production.

Design and synthesis of isosteviol triazole conjugates for cancer therapy.

One of the keys for successfully developing drugs against the broad spectrum of cancer cell types is structural diversity. In the current study, we focused on a family of isosteviol derivatives as potential novel antitumor agents. Isosteviol is a tetracyclic diterpenoid obtained by acid hydrolysis of steviol glycoside extracts isolated from abundant Stevia rebaudiana plants. In this work, we have designed and synthesized a panel of isosteviol triazole conjugates using "click" chemistry methodology. Evaluation of these compounds against a series of cancer cell lines derived from primary and metastatic tumors demonstrated that these conjugates exhibit cytotoxic activities with IC50 in the low µM range. In addition, their anti-proliferative activities are cancer cell type specific. Taken together, our studies underscore the importance of structural diversity in achieving cancer cell type specific drug development.

Radiation Biological Toximetry Using Circulating Cell-Free DNA (cfDNA) for Rapid Radiation/Nuclear Triage.

Optimal triage biodosimetry would include risk stratification within minutes, and it would provide useful triage despite heterogeneous dosimetry, cytokine therapy, mixed radiation quality, race, and age. For regulatory approval, the U.S. Food and Drug Administration (FDA) Biodosimetry Guidance requires suitability for purpose and a validated species-independent mechanism. Circulating cell-free DNA (cfDNA) concentration assays may provide such triage information. To test this hypothesis, cfDNA concentrations were measured in unprocessed monkey plasma using a branched DNA (bDNA) technique with a laboratory developed test. The cfDNA levels, along with hematopoietic parameters, were measured over a 7-day period in Rhesus macaques receiving total body radiation doses ranging from 1 to 6.5 Gy. Low-dose irradiation (0-2 Gy) was easily distinguished from high-dose whole-body exposures (5.5 and 6.5 Gy). Fold changes in cfDNA in the monkey model were comparable to those measured in a bone marrow transplant patient receiving a supralethal radiation dose, suggesting that the lethal threshold of cfDNA concentrations may be similar across species. Average cfDNA levels were 50 ± 40 ng/mL [±1 standard deviation (SD)] pre-irradiation, 120 ± 13 ng/mL at 1 Gy; 242 ± 71 ng/mL at 2 Gy; 607 ± 54 at 5.5 Gy; and 1585 ± 351 at 6.5 Gy (±1 SD). There was an exponential increase in cfDNA concentration with radiation dose. Comparison of the monkey model with the mouse model and the Guskova model, developed using Chernobyl responder data, further demonstrated correlation across species, supporting a similar mechanism of action. The test is available commercially in a Clinical Laboratory Improvement Amendments (CLIA) ready form in the U.S. and the European Union. The remaining challenges include developing methods for further simplification of specimen processing and assay evaluation, as well as more accurate calibration of the triage category with cfDNA concentration cutoffs.

Effects on Lung Tissue After Breast Cancer Radiation: Comparing Photon and Proton Therapies.

Purpose: In breast cancer, improved treatment approaches that reduce injury to lung tissue and early diagnosis and intervention for lung toxicity are increasingly important in survivorship. The aims of this study are to (1) compare lung tissue radiographic changes in women treated with conventional photon radiation therapy and those treated with proton therapy (PT), (2) assess the volume of lung irradiated to 5 Gy (V5) and 20 Gy (V20) by treatment modality, and (3) quantify the effects of V5, V20, time, and smoking history on the severity of tissue radiographic changes. Patients and Methods: A prospective observational study of female breast cancer patients was conducted to monitor postradiation subclinical lung tissue radiographic changes. Repeated follow-up x-ray computed tomography scans were acquired through 2 years after treatment. In-house software was used to quantify an internally normalized measure of pulmonary tissue density change over time from the computed tomography scans, emphasizing the 6- and 12-month time points. Results: Compared with photon therapy, PT was associated with significantly lower lung V5 and V20. Lung V20 (but not V5) correlated significantly with increased subclinical lung tissue radiographic changes 6 months after treatment, and neither correlated with lung effects at 12 months. Significant lung tissue density changes were present in photon therapy patients at 6 and 12 months but not in PT patients. Significant lung tissue density change persisted at 12 months in ever-smokers but not in never-smokers. Conclusion: Patients treated with PT had significantly lower radiation exposure to the lungs and less statistically significant tissue density change, suggesting decreased injury and/or improved recovery compared to photon therapy. These findings motivate additional studies in larger, randomized, and more diverse cohorts to further investigate the contributions of treatment modality and smoking regarding the short- and long-term radiographic effects of radiation on lung tissue.

The role of mitochondrial proteomic analysis in radiological accidents and terrorism.

In the wake of the 9/11 terrorist attacks and the recent Level 7 nuclear event at the Fukushima Daiichi plant, there has been heightened awareness of the possibility of radiological terrorism and accidents and the need for techniques to estimate radiation levels after such events. A number of approaches to monitoring radiation using biological markers have been published, including physical techniques, cytogenetic approaches, and direct, DNA-analysis approaches. Each approach has the potential to provide information that may be applied to the triage of an exposed population, but problems with development and application of devices or lengthy analyses limit their potential for widespread application. We present a post-irradiation observation with the potential for development into a rapid point-of-care device. Using simple mitochondrial proteomic analysis, we investigated irradiated and nonirradiated murine mitochondria and identified a protein mobility shift occurring at 2-3 Gy. We discuss the implications of this finding both in terms of possible mechanisms and potential applications in bio-radiation monitoring.

Tumor oxygen measurements and personalized medicine.

Tumor hypoxia is probably the most important not yet measurable factor that predicts the outcome of cancer therapy. Hypoxic tumors are resistant to radiation, chemotherapy, and surgery. They signal tumor cells to grow, invade, survive cytotoxic-factor assault, and increase metastatic activity. Therapies aimed at reversing hypoxia-related treatment resistance or normalizing hypoxia are proven effective with level 1 evidence. The weak link remains the lack of satisfactory methods of measurement of tumor oxygenation.