Dotting the eyes: mouse strain dependency of the lens epithelium to low dose radiation-induced DNA damage

PURPOSE

Epidemiological evidence regarding the radiosensitivity of the lens of the eye and radiation cataract development has led to changes in the EU Basic Safety Standards for protection of the lens against ionizing radiation. However, mechanistic details of lens radiation response pathways and their significance for cataractogenesis remain unclear. Radiation-induced DNA damage and the potential impairment of repair pathways within the lens epithelium, a cell monolayer that covers the anterior hemisphere of the lens, are likely to be involved.

MATERIALS AND METHODS

In this work, the lens epithelium has been analyzed for its DNA double-strand break (DSB) repair response to ionizing radiation. The responses of epithelial cells located at the anterior pole (central region) have been compared to at the very periphery of the monolayer (germinative and transitional zones). Described here are the different responses in the two regions and across four strains (C57BL/6, 129S2, BALB/c and CBA/Ca) over a low dose (0-25 mGy) in-vivo whole body X-irradiation range up to 24 hours post exposure.

RESULTS

DNA damage and repair as visualized through 53BP1 staining was present across the lens epithelium, although repair kinetics appeared non-uniform. Epithelial cells in the central region have significantly more 53BP1 foci. The sensitivities of different mouse strains have also been compared.

CONCLUSIONS

129S2 and BALB/c showed higher levels of DNA damage, with BALB/c showing significantly less inter-individual variability and appearing to be a more robust model for future DNA damage and repair studies. As a result of this study, BALB/c was identified as a suitable radiosensitive lens strain to detect and quantify early low dose ionizing radiation DNA damage effects in the mouse eye lens specifically, as an indicator of cataract formation.

Correlates of Refusal of Surgery in the Treatment of Non-metastatic Pancreatic Adenocarcinoma

BACKGROUND

Surgical resection is the most important therapeutic intervention for eligible patients with pancreatic cancer; however, a majority of patients never receive surgery for a variety of reasons, including patient refusal. Utilizing the National Cancer Database, we investigated the associated sociodemographic and clinical factors for those patients who refused surgery, and the impact of this decision on overall survival (OS).

METHODS AND MATERIALS

We analyzed adult patients with non-metastatic adenocarcinoma of the pancreas diagnosed from 2004 to 2013. Univariate and multivariate logistic regression modeling was used to identify factors predictive of refusing surgery, and Kaplan-Meier and log-rank analysis was performed to investigate the effect on OS.

RESULTS

A total of 48,902 patients were identified: 47,107 received surgery (96.3%) and 1795 were offered surgery but refused (3.7%). Factors associated with refusing surgery include both sociodemographic factors [age > 50 years, female sex, Black race, non-private insurance, treatment at a non-academic institution or non-metro facility, Carlson Comorbidity Index of 2 + (p ≤ 0.01)], and clinical factors [advanced clinical T (tumor) category and tumor size > 20 cm (p ≤ 0.01)]. Patients who refused surgery and received no treatment at all experienced a median survival of 5.1 months, while those who refused surgery but received chemoradiotherapy experienced a median survival of 11.2 months. As an index for comparison, those who received surgery had a median survival of 20.5 months.

CONCLUSION

Refusing surgery is an understudied phenomenon associated with several sociodemographic and clinical factors. The expected prognosis for patients who refuse surgery is presented.

Adjuvant radiation for T1-2N1 oral cavity cancer survival outcomes and utilization treatment trends: Analysis of the SEER database

OBJECTIVE

Evaluate current practice patterns in the use of adjuvant radiation for T1-2N1 OCSCC patients and investigate its efficacy in the population-based setting.

MATERIALS AND METHODS

This study extracted patients who were treated surgically for T1N1 and T2N1 OCSCC without adverse nodal features from the SEER database from 2004 to 2013. Patients with distant metastatic disease, unknown surgery or radiation status, or prior malignancies were excluded. Patients were divided into those who underwent surgical resection with and without adjuvant radiation. Disease-specific survival (DSS) and overall survival (OS) were the primary outcomes measured.

RESULTS

746 patients met inclusion criteria and 70% received adjuvant radiation therapy. Treatment with adjuvant radiation therapy was significantly associated with improved 5-year DSS (65% versus 51%; p < 0.001) and OS (54% versus 44%; p = 0.007) for T1N1 tumors. Likewise, improved 5-year DSS (58% versus 38%; p = 0.009) and OS (48% versus 28%; p = 0.004) was shown in T2N1 tumors. Patients with T2N1 tumors wer significantly more likely to receive adjuvant radiation (75% versus 63%; p < 0.001). Those with insurance and high risk primary subsites: buccal, retromolar trigone, and hard palate were more likely to receive adjuvant radiation. The percent utilization of adjuvant radiation remained constant through the study period for T2N1 tumors (72-74%) but significantly decreased for T1N1 (71-55%) (p = 0.047).

CONCLUSION

Adjuvant radiation therapy is independently associated with a significant survival benefit for patients with both T1N1 and T2N1 OCSCC. However, this study demonstrates that patients with T1N1 cancer are less likely to receive adjuvant radiation and utilization is decreasing.

Benefit of adjuvant chemotherapy based on lymph node involvement for oesophageal cancer following trimodality therapy

Background

Oesophageal cancer (OC) survival rates have improved since the widespread adoption of neoadjuvant chemoradiation therapy (NACRT) followed by oesophagectomy (trimodality therapy). Unfortunately, the overall prognosis for patients with locally advanced disease remains poor. In this study, we sought to assess the effect of adjuvant chemotherapy (AC) in patients treated with trimodality therapy.

Methods

Using the National Cancer Database we retrospectively identified 6785 patients with locally advanced (cT1b-T4a, N0-N+, M0) OC who were treated with trimodality therapy from 2006 to 2014. Patients were separated based on receipt of AC (n=463), as well as clinical and pathological lymph node involvement. Overall survival (OS) between groups was compared using the Kaplan-Meier method and Cox proportional hazard modelling.

Results

Based on multivariate analysis, AC was associated with a statistically significantly reduced risk of death (HR 0.77, p<0.001). Subgroup analysis revealed that AC was associated with reduced risk of death compared with NACRT alone in the cN+/pN0 (median OS 64 vs 43 months; p=0.019) and the cN+/pN+ (median OS 27 vs 22 months; p=0.010) groups, but not in the cN0/pN0 (median OS 48 vs 49 months; p=0.253) or cN0/pN+ (median OS 31 vs 24 months; p=0.077) groups.

Conclusion

AC following trimodality therapy may improve survival in patients with locally advanced OC. Patients who undergo lymph node downstaging may be the most likely to benefit from AC. Prospective studies are needed to confirm this finding.

Academic Facility Utilization and Survival Outcomes in Adult Head and Neck Sarcomas: An NCDB Analysis

Objectives

To investigate clinicopathologic and treatment factors associated with survival in adult head and neck sarcomas in the National Cancer Database (NCDB). To analyze whether treatment settings and therapies received influence survival outcomes and to compare trends in utilization via an aggregated national data set.

Study Design

Prospectively gathered data.

Setting

NCDB.

Subjects and Methods

The study comprised a total of 6944 adult patients treated for a head and neck sarcoma from January 2004 to December 2013. Overall survival (OS) was the primary outcome.

Results

Increased age and tumor size, nodal involvement, and poorly differentiated histology had significantly reduced OS ( P < .001). Angiosarcoma, malignant nerve sheath tumor, malignant fibrous histiocytoma, osteosarcoma, and rhabdomyosarcoma histologic subtypes had significantly reduced OS, while liposarcoma, chondrosarcoma, and chordoma had improved OS ( P < .001). Utilization of surgical therapy was associated with improved OS, while positive surgical margins were associated with treatment at a community-based cancer program and had reduced OS ( P < .001). On multivariate analysis, treatment with radiation and/or chemotherapy was not significantly associated with OS; however, primary treatment with definitive chemoradiotherapy had significantly reduced OS. Patients treated at academic/research cancer programs (n = 3874) had significantly improved 5- and 10-year OS (65% and 54%, respectively) when compared with patients treated at community-based cancer programs (n = 3027; 49% and 29%; P < .001). The percentage utilization of these programs (56% vs 44%) did not change over the study period.

Conclusion

For adult head and neck sarcomas, treatment at an academic/research cancer program was associated with improved survival; however, despite increasing medical specialization, the percentage utilization of these programs for this rare tumor remains constant.

Clinical Evaluation of a New Two-Site Assay for CA125 Antigen

As appropriate surgery and chemotherapy can improve both quality of life and survival of patients with ovarian adenocarcinoma, there has been a pressing need for “serodiagnostic” assays to enable close patient monitoring. CA 125 antigen has previously been described as a useful tumor marker of ovarian cancer. This is the first clinical evaluation of a radioimmunoassay using two new monoclonal antibodies, B27.1 and B43.13, that react with separate sites on the glycoprotein marker CA 125. Using the new assay, the majority of patients with clinically or radiologically detectable disease had serum CA 125 antigen levels well above the upper limit seen with random apparently healthy donors, while only three patients who were believed free of disease had elevated levels. Disease progression was associated with increasing values of serum CA 125 antigen, while response to therapy was associated with a steady decline in serum CA 125 antigen levels. Seven patients had steadily rising serum CA 125 antigen levels after initially having normal levels. The mean lead time between rise above normal and clinical or radiological evidence of relapse was 5 months (range 2 to 12 months). The merits of further surgical intervention are illustrated by the serial values of two patients followed after chemotherapy.

The assay appears to have value in monitoring response to therapy and in detecting disease relapse at a time when appropriate therapeutic intervention is still possible or likely to be beneficial. Furthermore, monitoring CA 125 antigen was shown to be of benefit in assessing response to chemotherapy in a few patients with metastatic adenocarcinoma of unknown primary, and may be useful in this group of patients in determining those likely to benefit from aggressive chemotherapy.

Possible Utility of Serum Determinations of CA 125 and CA 27.29 in Breast Cancer Management

The utility of measurement of serum levels of the tumor associated antigens CA 125 and CA 27.29 in detecting the presence of disease and in monitoring changes in disease status was examined in 63 patients with breast cancer. In patients with clinically detectable disease the CA 125 level was elevated in 59%, the CA 27.29 level in 59.5% and one or both markers in 84.6%. Specificity for presence of disease was 83.6% for CA 125, 88% for CA 27.29, and 69.1% for the two markers combined. Changes in marker levels of more than 50% correlated with clinical changes in disease status in 58% of cases for either CA 125 or CA 27.29 alone. In 87.5% of cases with clinically progressive disease one or both marker levels increased by more than 50% from the previous levels. In no case with greater than 50% increase in a marker level was there regression of disease. Thus, the use of these markers in combination might have utility in cases where diagnosis of recurrent disease is difficult or where monitoring of response to treatment is hampered by lack of measurable disease.

Long-term risk of cardiovascular disease among colorectal cancer survivors in a population-based cohort study

113

Background: In the United States, colorectal cancer is the fourth most common cancer and one of the leading causes of cancer death. Few studies have examined the relationship between colorectal cancer survivorship and long-term cardiovascular disease (CVD) risk. Methods: Individuals diagnosed with colorectal cancer were identified using the Utah Population Database. For a comparison group, up to 5 cancer-free individuals were matched by birth year, birth state, follow-up time and sex to each cancer case. For individuals with > 10 years of follow-up, we estimated CVD risk > 10 years after cancer diagnosis. Cox regression models were used to estimate hazard ratios (HR) and 95% Confidence Intervals. Results: Among 1,749 colorectal cancer survivors who had survived for at least 10 years, 1,001 (57.2%) were diagnosed with CVD > 10 years after cancer diagnosis. Compared to the general population, colorectal cancer survivors had an increased risk of CVD > 10 years after cancer diagnosis: HR = 2.84 (95% CI = 2.59, 3.11) for hypertension; HR = 2.66 (95% CI 2.37, 2.98) for diseases of the heart; HR = 3.91 (95% CI = 3.33, 4.58) for diseases of the arteries, arterioles and capillaries; HR = 2.58 (95% CI = 2.46, 2.99) for diseases of the veins and lymphatics; HR = 2.98 (95% CI = 2.36, 3.76) for cerebrovascular disease. Colorectal cancer survivors with ≥1 comorbidity had an increased risk of CVD > 10 years after cancer diagnosis compared to survivors with no comorbidities (HR = 1.7, 95% CI = 1.49, 1.95). Colorectal cancer survivors who were ≥65 years had an increased risk of CVD > 10 years after cancer diagnosis. Colorectal cancer survivors who were obese at the time of diagnosis had an increased risk of CVD > 10 years after cancer diagnosis when compared to survivors with normal BMIs (HR = 1.25; 95% CI = 1.06, 1.49). Conclusions: Compared to the general population, colorectal cancer survivors had an increased risk of CVD during the > 10 year follow-up period. Within colorectal cancer survivors, there was an increased risk of CVD for those that were older, had ≥1 comorbidity and were obese. The increased risk of CVD among survivors may be attributable to the lifestyle risk factors shared by colorectal cancer and CVD.

Digital Mammography: A World without Film?

Objectives: eDiaMoND is a next generation Internet (”Grid”) multidisciplinary research project funded by the UK e-Science Programme with the following objectives; the development of a next generation Internet enabled prototype to demonstrate the potential benefits of a national infrastructure to support digital mammography; the exploration of potential benefits for digital mammography systems, with particular emphasis being placed on selected applications, namely, screening, training, computer-aided detection and appropriate support for epidemiological studies.

Methods: EDiaMoND has worked in conjunction with selected clinical partners to enable the collection of valuable mammography information and the design of applications based upon extensive requirements gathering exercises. The clinical partners validated both the immediate needs and assisted with defining future needs of such an architecture to support the UK Health Service.

Results: The project has succeeded in invoking the interest of clinical partners and representatives of the UK NHS Breast Screening Programme in our vision of a world without film, albeit a long way off. The project has also succeeded in identifying the barriers to adopting this approach with the current limitations within the NHS, and has developed a blueprint for working towards this strategy.

Conclusions: A UK national digital mammography archive has the potential to provide major benefits for the UK. For example, such an archive could: ensure that previous mammograms are always available, and could link up seamlessly the screening, assessment and symptomatic clinics; it could provide a huge teaching and training resource; it could be a huge resource for epidemiological studies.

Postoperative chemotherapy in patients who are pN+ following neoadjuvant chemoradiation for locally advanced esophageal cancer

97

Background: Esophageal cancer survival rates have improved since the widespread adoption of neoadjuvant chemoradiation therapy (CRT) followed by esophagectomy for patients who present with locally advanced disease. Unfortunately, overall prognosis for these patients remains poor. In this study, we sought to assess the effect of additional adjuvant chemotherapy in patients who have positive lymph nodes (pN+) following surgery. Methods: Using the National Cancer Database we retrospectively identified all patients with locally advanced esophageal cancer who received neoadjuvant CRT from 2004 to 2014. We then identified patients within this dataset who were found to be pN+ following neoadjuvant chemoradiation and esophagectomy and categorized them as having received adjuvant chemotherapy versus no additional chemotherapy. Survival analysis was performed using Kaplan-Meier estimation and propensity score matching. Results: 2,045 patients were identified as being pN+ following neoadjuvant CRT. Within this group, 14% received adjuvant chemotherapy. The 1, 5, and 8 year overall survival (OS) of patients receiving adjuvant therapy was 87%, 30%, and 21% compared to 76%, 23%, and 16% in those receiving neoadjuvant therapy alone, respectively (p = 0.0017). After a propensity score matched analysis, median OS was found to be significantly longer in the those receiving neoadjuvant CRT plus adjuvant chemotherapy compared to neoadjuvant CRT alone (27.8 months vs 22.2 months; HR 0.78; 95% CI, 0.62 to 0.97; p = 0.032). Conclusions: While not currently the standard of care, our data suggests that adjuvant chemotherapy may improve survival in patients with locally advanced esophageal cancer who are found to be pN+ following surgery. Additional prospective studies are needed to confirm this finding.

The effect of adjuvant chemotherapy in patients without local nodal metastases following neoadjuvant chemoradiotherapy and esophagectomy for locally advanced esophageal cancer

111

Background: Neoadjuvant chemoradiation therapy (CRT) followed by esophagectomy is the current standard of care for patients with locally advanced esophageal cancer. The potential benefit of additional postoperative chemotherapy is still under investigation. In this study, we utilized the National Cancer Database to assess the effect of adjuvant chemotherapy in patients who were found to have node negative disease (pN0) following surgery. Methods: Patients with locally advanced esophageal cancer who received neoadjuvant CRT followed by esophagectomy from 2004 to 2014 were retrospectively identified using the National Cancer Database. Patients who were postoperatively staged as pN0 were then separated based on whether or not they received adjuvant chemotherapy. Using Kaplan-Meier estimation and a multivariate cox regression analysis, the overall survival of those who received adjuvant therapy was then compared to those who received neoadjuvant CRT alone. Results: 3,159 patients with locally advanced esophageal cancer underwent neoadjuvant CRT and were found to be pN0 following surgery. 119 of these patients received postoperative chemotherapy. The 1, 5, and 8-year overall survival in those receiving adjuvant therapy was 95.9%, 49.9%, and 47.7% compared to 85.8%, 44.6%, and 33.0% in those receiving neoadjuvant CRT alone, respectively (p = 0.019). Based on multivariate analysis, receiving adjuvant chemotherapy was independently associated with increased overall survival (p = 0.011; HR 0.658; 95% CI, 0.476 to 0.908). Conclusions: Adjuvant chemotherapy may improve survival in patients with locally advance esophageal cancer who have no evidence of local nodal metastases following surgery. Additional clinical trials are needed to further confirm which patients may benefit from adjuvant therapy and to determine the optimal postoperative therapeutic regimen.

Value of surgical resection and timing of therapy in patients with pancreatic cancer at high risk for positive margins

Background

Surgical resection remains the best chance at long-term survival in pancreatic cancer, though margin-positive resections are associated with diminished survival. We examined the effect of margin-positive resection on survival, as well as the role and timing of additional therapies through the National Cancer Database (NCDB).

Patients and methods

Patients with stage IIA–III pancreatic adenocarcinoma diagnosed from 2004 to 2013 were identified in NCDB. Survival was compared using univariate and multivariate Cox proportional hazards modelling for patients who underwent surgery with negative (R0), microscopically positive (R1) and macroscopically positive (R2) margins or non-surgical treatment. We further analysed patients by margin status, timing of additional therapy (neoadjuvant therapy (NAT) vs adjuvant therapy (AT) vs none) and clinical stage.

Results

We analysed 44 852 patients. Median survival (MS) for patients who did not undergo surgery was 10.3 months, compared with 19.7 months for R0 (P<0.001), 14.3 months for R1 (P<0.001) and 9.8 months (P=0.07) for R2 resections. NAT (MS 23.2 months) was associated with improved survival compared with AT (MS 21.5 months) in negative-margin patients and equivalent (MS 17.6 months) to AT (MS 16.8 months) in positive-margin patients. Survival for stage III NAT positive-margin patients (MS 19.8 months) was equivalent to AT after negative margins (MS 18.4 months, P=1.00). Improved R0 rates were seen with NAT (88% vs 81%, P<0.001), especially in stage III patients (85% vs 59%, P<0.001).

Conclusion

R1 resections portend poorer survival than R0 but do not negate the benefit of surgery when additional therapy is given. NAT was associated with improved R0 rates and improved survival for stage III positive-margin patients.

Cross-sectional follow-up of voice outcomes in children who have a history of airway reconstruction surgery

OBJECTIVES

This study reports vocal function in a cross-section of children with subglottic stenosis. Each child had a history of laryngotracheal reconstruction and/or cricotracheal resection surgery. Vocal function was measured using laryngoscopy, acoustic analysis, perceptual evaluation and impact of voice on quality of life.

DESIGN

All patients aged >5 years with history of laryngotracheal reconstruction and/or cricotracheal resection surgery at the Scottish National Complex Airways service were invited to participate.

SETTING

Data were gathered in the Royal Hospital for Children in Glasgow in a single outpatient appointment.

PARTICIPANTS

Twelve of 56 former patients (aged 5-27) provided a voice sample and eleven consented to awake laryngoscopy. All consented for detailed evaluation of their medical records.

MAIN OUTCOME MEASURES

Acoustic analysis of fundamental frequency and pitch perturbation was conducted on sustained vowel [a]. Perceptual evaluation was conducted by 4 trained listeners on a series of spoken sentences. Impact on quality of life was measured using the paediatric voice-related quality of life questionnaire. Laryngeal function was descriptively evaluated.

RESULTS

Four children had normal voice acoustically, perceptually and in relation to voice-related quality of life. One of these had vocal fold nodules unrelated to surgical history. Two other children had "near normal" vocal function, defined where most voice measurements fell within the normal range.

CONCLUSIONS

Normal or "near normal" voice is a possible outcome for children who have had this surgery. Where there is an ongoing complex medical condition, voice outcome may be poorer.

Chemoradiation Therapy for Unresected Extrahepatic Cholangiocarcinoma: A Propensity Score-Matched Analysis

BACKGROUND

Unresected extrahepatic cholangiocarcinoma (uEHCC) remains a deadly disease. Guidelines for uEHCC recommend either chemotherapy alone (CT) or chemoradiotherapy (CRT). This study used the National Cancer Database (NCDB) to compare outcomes for patients treated with CT and those who underwent CRT.

METHODS

Patients with initially diagnosed non-metastatic uEHCC from 2004 to 2014 were identified. Using Chi square analysis, patients who underwent CT were compared with those who received CRT. Uni- and multivariate Cox regression analyses were used to compare characteristics related to survival. Propensity score matching and shared frailty analysis were undertaken to correct for baseline differences between the two groups. Additional analyses were performed to compare survival for the minority of patients who underwent surgery and advanced-stage patients.

RESULTS

The study identified 2996 patients with uEHCC. Chemoradiation was associated with better survival (median survival [MS], 14.5 months; hazard ratio [HR] 0.84; p < 0.001) than CT alone (MS, 12.6 months). Induction of CT before CRT was associated with a trend toward decreased risk of death compared with concurrent CRT (HR 0.81; p = 0.051). For the patients able to undergo surgery after initial treatment, MS was 24.5 months (HR 0.38; p < 0.001) versus 12.2 months for those who had no surgery. For these patients, CRT also was associated with better survival (MS, 31.2 months; HR 0.66; p = 0.001) than CT (MS, 22.1 months). Positive margins at surgery yielded survival equivalent to that with no surgery.

CONCLUSION

Although CRT may be associated with slightly better survival in uEHCC than CT alone, the majority of the benefit was observed for patients able to undergo eventual surgery.