Faculty Bibliography

PURPOSE/OBJECTIVE:To determine the impact of fellow, resident, or medical student (MS) involvement on outcomes in patients undergoing permanent (125)I prostate seed implant. METHODS AND MATERIALS/METHODS:The study population consisted of men with clinically localized low/intermediate-risk prostate cancer treated with low-dose-rate permanent interstitial brachytherapy. Cases were stratified according to resident, fellow, MS, or attending involvement. Outcomes were compared using analysis of variance, logistic regression, and log rank tests. RESULTS:A total of 291 patients were evaluated. Fellows, residents, and MS were involved in 47 (16.2%), 231 (79.4%), and 34 (11.7%) cases, respectively. Thirteen (4.4%) cases were completed by an attending physician alone. There was no difference in freedom from biochemical failure when comparing the resident, fellow, or attending alone groups (p = 0.10). There was no difference in V100 (volume of the prostate receiving 100% of the prescription dose) outcomes when comparing resident cases to fellow cases (p = 0.72) or attending alone cases (p = 0.78). There was no difference in D90 (minimum dose covering 90% of the postimplant volume) outcomes when comparing resident cases to fellow cases (p = 0.74) or attending alone cases (p = 0.58). When examining treatment toxicity, fellow cases had higher rates of acute Grade 2 + GU toxicity (p = 0.028). With the exception of higher urethra D90 among PGY 2-3 cases (p = 0.02), dosimetric outcomes were similar to cases with PGY 4-5 resident participation. There was no difference in outcomes for cases with and without MS participation. CONCLUSIONS:Interstitial prostate seed implants can be safely performed by trainees with appropriate supervision. Hands-on brachytherapy training is effective and feasible for trainees.

PURPOSE/OBJECTIVE:The purposes of this study were to assess the exposure that medical students (MSs) have to radiation oncology (RO) during the course of their medical school career, as evidenced by 2 time points in current medical training (ie, first vs fourth year; MS1s and MS4s, respectively) and to assess the knowledge of MS1s, MS4s, and primary care physicians (PCPs) about the appropriateness of RT in cancer management in comparison with RO attendings. METHODS:We developed and beta tested an electronic survey divided into 3 parts: RO job descriptions, appropriateness of RT, and toxicities of RT. The surveys were distributed to 7 medical schools in the United States. A concordance of >90% (either yes or no) among RO attendings in an answer was necessary to determine the correct answer and to compare with other subgroups using a χ(2) test (P<.05 was significant). RESULTS:The overall response rate for ROs, MS1s, MS4s, and PCPs was 26%; n (22 + 315 + 404 + 43)/3004. RT misconceptions decreased with increasing level of training. More than 1 of 10 MSs did not believe that RT alone could cure cancer. Emergent oncologic conditions for RT (eg, spinal cord compression, superior vena cava syndrome) could not be identified by >1 of 5 respondents. Multiple nontoxicities of RT (eg, emitting low-level radiation from the treatment site) were incorrectly identified as toxicities by >1 of 5 respondents. MS4s/PCPs with an RO rotation in medical school had improved scores in all prompts. CONCLUSIONS:Although MS knowledge of general RT principles improves from the first to the fourth year, a large knowledge gap still exists between MSs, current PCPs, and ROs. Some basic misconceptions of RT persist among a minority of MSs and PCPs. We recommend implementing formal education in RO fundamentals during the core curriculum of medical school.

BACKGROUND:Although tri-modality therapy is an acceptable standard of care in patients with locally advanced esophageal cancer, data regarding patterns of failure is lacking. We report bi-institutional patterns of failure experience treating patients using tri-modality therapy. MATERIALS AND METHODS/METHODS:We retrospectively reviewed patients who underwent chemoradiation followed by esophagectomy between 2006 and 2011 at two NCI-designated cancer centers. First failure sites were categorized as local, regional nodal, or distant. Statistical analysis was performed using Fisher's exact test, non-parametric Wilcoxon rank-sum test, and multiple logistic regression. Kaplan-Meier curves were generated for relapse-free survival (RFS) and overall survival. RESULTS:A total of 132 patients met the inclusion criteria with a median age of 62 (range 36-80) and median follow-up of 28 months (range 4-128). There were a total of six (4.5%) local, 13 (10%) regional nodal, and 32 (23.5%) distant failures. Local failure was correlated with fewer lymph nodes (LN) assessed (p = 0.01) and close/positive margins (p < 0.01). Regional nodal failure was correlated with fewer LN assessed (p < 0.01) and larger pretreatment tumor size (p = 0.04). Patients with ≤13 LN evaluated had an inferior locoregional RFS versus patients with >13 LN evaluated (p = 0.003). Distant recurrence was correlated with higher pathologic nodal stage (p < 0.001), ulceration (p = 0.017), perineural invasion (p = 0.029), residual disease (p = 0.004), and higher post-treatment PET SUV max (p = 0.049). Patients with a pathologic complete response (OR 0.19, 95% CI 0.05-0.68) were less likely to experience distant recurrence. CONCLUSION/CONCLUSIONS:Tumor and treatment factors may predict for failure in patients undergoing tri-modality therapy for locally advanced esophageal cancer. Further data is needed to identify patterns of failure in these patients.

PURPOSE/OBJECTIVE:Patients with pancreatic adenocarcinoma (PAC) are often treated with neoadjuvant chemoradiation (NACRT) in hopes of downstaging their disease for potential surgical resection. We hypothesized that increasing the radiation dose to the area of the tumor abutting the vessel(s) of concern would increase the rate of surgical resection in patients with borderline resectable PAC (BRPAC) and locally advanced PAC (LAPAC) treated with NACRT. METHODS AND MATERIALS/METHODS:We retrospectively reviewed consecutive cases of BRPAC and LAPAC treated with NACRT from January 2006 to December 2013, with or without a vessel boost (VB), at a single institution. The primary endpoints were rate of R0/R1 potentially curative surgical resection and acute toxicity. Univariate analysis with the Fisher exact test was performed to evaluate the effect of each variable. Multiple logistic regression was used to adjust for the following covariates: year of diagnosis, age, sex, carbohydrate antigen 19-9 (CA19-9) level at diagnosis, and BRPAC or LAPAC. RESULTS:Of the 104 patients identified, 22% (n = 23) received a VB (median, 54 Gy; range, 54-64 Gy), and 78% (n = 81) received no boost (median, 50.4 Gy; range, 48.6-52.2 Gy). More patients in the VB group were treated from 2010 to 2013 (P < .001) and with intensity modulated radiation therapy (P = .002). Other baseline characteristics were balanced. After adjustment for covariates, there was a statistical trend toward increased surgical resection in patients who received a VB (odds ratio [OR], 2.77; 95% confidence interval [CI], 0.89-8.57; P = .077). Age (≥70 years; OR, 0.42; 95% CI, 0.16-1.05; P = .064) and LAPAC (OR, 0.32; 95% CI, 0.09-1.09; P = .068) also trended toward significance. CA19-9 ≥47.9 U/mL (OR, 0.24; 95% CI, 0.08-0.71; P = .010) was significant on multivariate analysis. There was no significant difference in acute or late toxicity between groups. CONCLUSIONS:In our retrospective series, dose escalation was associated with an improved surgical resection rate in BRPAC and LAPAC patients treated with NACRT, although this improvement was not statistically significant.

BACKGROUND:The interval between neoadjuvant chemoradiation treatment and surgery has been described as an important predictor of pathologic response to therapy in nonesophageal cancer sites. We retrospectively reviewed our experience with patients who underwent neoadjuvant chemoradiation and esophagectomy to better understand the impact of the timing of surgery on pathologic complete response rates in esophageal cancer. METHODS:Two hundred thirty-one sequentially treated patients from 2000 to 2011 were identified for this study; 88 of these patients completed neoadjuvant chemoradiation followed by esophagectomy at our institution. The interval between completion of chemoradiation and surgery was calculated for each patient. The patients were categorized into quartiles and also into 3-week interval groups. Treatment factors and surgical morbidity data, including the estimated blood loss and length of operative stay, were also assessed. RESULTS:Quartiles for the neoadjuvant chemoradiation to surgery interval were less than 45 days, 46 to 50 days, 51 to 63 days, and 64+ days. Corresponding pathologic complete response rates were 12.5%, 20.0%, 22.7%, and 40.9% (p = 0.03). Results for 3-week intervals were similar (p = 0.02). There was no association between increasing time interval between the ending of neoadjuvant chemoradiation to surgery and length of stay longer than 2 weeks. CONCLUSIONS:A longer interval between completion of neoadjuvant chemoradiation and surgery was associated with higher pathologic complete response rates without an impact on surgical morbidity.

BACKGROUND AND OBJECTIVES/OBJECTIVE:To identify the impact of the interval between chemoradiation to surgery on morbidity and mortality in patients undergoing tri-modality therapy for esophageal cancer. METHODS:Eighty-five patients completed chemoradiation followed by esophagectomy between 2006 and 2011. The interval between completion of chemoradiation and surgery was calculated for each patient. We evaluated the association of quartiles and 3-week groups with morbidity and mortality using logistic regression. Other treatment and clinical factors were also assessed. RESULTS:A total of 59 patients(69%) experienced at least one complication. When examining specific complications, patients with pulmonary complications had a longer mean time interval from chemoradiation to surgery (P = 0.02). Linear regression showed an association between longer interval between chemoradiation to surgery and hospital length of stay (LOS) >14 days when analyzing by both interval quartile (P = 0.04) and 3-week intervals (P = 0.04). On multivariable analysis, increased time interval predicted for pulmonary complications (P < 0.01) and LOS >14 days (P = 0.03). When examining other treatment factors, squamous cell histology (P = 0.02) also predicted for a hospital length of stay >14 days. CONCLUSIONS:Factors such as interval between completion of chemoradiation and surgery and squamous cell histology may be associated with surgical morbidity. Further data is warranted to confirm these findings.

OBJECTIVE:To examine the utilization of radiation therapy (RT) in patients with renal cell carcinoma (RCC) using a large national tumor registry. MATERIALS AND METHODS/METHODS:Patients diagnosed with RCC were identified using the National Cancer Data Base. Our primary objective was to assess temporal trends in the utilization of RT. Our secondary objective was to identify patient and treatment factors associated with receipt of RT. The Cochran-Armitage test was used for trend analysis. Multivariable logistic regression was performed to identify factors associated with RT use. RESULTS:A total of 279,427 patients were diagnosed with RCC from 1998 to 2010. A total of 233,572 (83.6%) had localized or locally advanced disease, whereas the remaining 45,855 (16.4%) had metastatic disease. There was a decrease in radiotherapy across all patients during this period (1.5%-0.6%, P <.001); as salvage or adjuvant therapy with surgery (1.3%-0.3%, P <.001), and in patients with metastatic disease (33.3%-28.5%, P <.001). Factors associated with increased RT use in patients with nonmetastatic RCC included male gender, receipt of systemic therapy, higher stage, higher grade, nonacademic treatment facility, facility location, and sarcomatoid or other histology. CONCLUSION/CONCLUSIONS:In the National Cancer Data Base, we observed a decrease in the use of RT for patients with RCC from 1998 to 2010. Patients with more aggressive disease characteristics were more likely to receive RT. Well-designed clinical trials are needed to clarify the role of RT in the management of these patients.

PURPOSE/OBJECTIVE:To determine whether computed tomography/magnetic resonance imaging-based day 0 (d0) dosimetry is a meaningful predictor of day 21 (d21) dosimetry in low-dose-rate brachytherapy for localized prostate cancer. METHODS AND MATERIALS/METHODS:The study population consisted of 277 men with localized (T1-2 N0 M0), low-/intermediate-risk prostate cancer treated with low-dose-rate brachytherapy. Computed tomography/magnetic resonance imaging fusion was used for postimplant dosimetry at d0 and d21. Logistic regression was used to construct receiver operating characteristic curves for achieving each constraint at d21, based on d0 D90 and V100, and Youden's index was used to evaluate cutpoints. Freedom from biochemical failure (FBCF) was estimated with the Kaplan-Meier method. RESULTS:The median d0 D90 increased from 133 to 150 Gy at d21, and median d0 V100 increased from 87% to 91%. For achieving the D90 constraint at d21, the optimal cut-point for d0 D90 was 135 Gy, with 84% of these patients maintaining a d21 D90 > 145 Gy. For achieving the D90 constraint at d21, the optimal cut-point for d0 V100 was 87%, with 83% of these patients maintained a d21 V100 > 90%. There was no improvement in FBCF in patients with a d0 D90 > 135 Gy or D90 > 145 Gy. Similarly, there was no improvement in FBCF in patients with a d0 V100 > 87% or V100 > 90%. CONCLUSIONS:Meeting dosimetric constraints on d0 does not obviate d21 dosimetric analysis. Constraints used for dose prescriptions on d0 are not the ideal predictors of d21 dosimetry.

Multifocal and multicentric breast cancers have been correlated with poor prognostic factors and worse outcomes versus unifocal disease. We evaluated the impact of multifocal and multicentric disease versus case controls with unifocal disease, matching for age, grade, T-, and N-stage. A total of 110 patients with multifocal (n = 93) or multicentric (n = 17) disease and 263 matched case controls were identified with a median follow-up of 53 months and 64 months, respectively. The actuarial local control rates for the multifocal/multicentric and unifocal group were 88% and 97%, respectively at both 5 and 10 years (p < 0.001). On multivariate analysis, multifocal/multicentric disease remained associated with higher local recurrence after controlling for other covariates including surgery type. The disease-free survival rates in the multifocal/multicentric group at 5 and 10 years were 75% and 71%, respectively, versus 87% and 78% at 10 years (p = 0.01). On multivariate analysis, multifocal/multicentric disease was no longer associated with worse disease-free survival. There was no difference in the cohorts in terms of regional control, overall survival, or cancer specific survival. Our findings suggest that multifocal/multicentric disease may be associated with worse outcomes versus unifocal disease regardless of type of surgery. This suggests a more biologically aggressive cancer and may be an important consideration when managing these patients. Further studies are needed to better understand the impact of multifocal/multicentric breast cancers on outcomes.

Stereotactic body radiotherapy is the preferred treatment modality for patients with inoperable early stage lung cancer. Chest wall toxicity is a potentially dose limiting side effect and may include fractures or pain secondary to treatment. The pathophysiology of these symptoms is unclear although it is presumed that radiation may alter the bone's normal tissue environment, affecting maintenance and remodeling. Chest wall pain is likely neuropathic secondary to injury to the intercostal nerves. Identifying patients with chest wall toxicity can be difficult due to the varying definitions of toxicity as well as heterogeneous contouring guidelines. Multiple studies have demonstrated a correlation between treatment factors and the incidence of chest wall toxicity. An increase in dose and treatment volume appear to be the most consistent radiation factors associated with toxicity. Patient factors such as body mass index, female gender, tumor location, and age have also been correlated with an increased likelihood of developing side effects. Management of chest wall toxicity is typically conservative using analgesic medications although surgical intervention may be required for displaced fractures. In this review, we examine the treatment, patient, and tumor factors predictive for chest wall toxicity and the implications for the treating physician.