Faculty Bibliography

BACKGROUND:Bone metastases cause significant morbidity in patients with cancer, and radiation therapy (RT) is an effective treatment approach. Indications for more complex ablative techniques are emerging. We sought to evaluate RT trends at a large multi-site tertiary cancer center. METHODS:Patients who received RT for bone metastases at a single institution (including regional outpatient clinics) from 2016 to 2018 were identified. Patients were grouped by RT regimen: single-fraction conventional RT (8 Gy × 1), 30 Gy in 10 fractions, SBRT, and "other". Multinomial logistic regression was performed to assess trends in regimens over time. Binary logistic regression was performed to evaluate factors associated with receipt of SBRT. RESULTS:Between 2016 and 2018, 5,952 RT episodes were received by 2,969 patients with bone metastases. Overall, 76% of episodes were ≤ 5 fractions. The median number of fractions planned for SBRT and non-SBRT episodes was 3 (IQR 3-3) and 5 (IQR 5-10), respectively. Use of SBRT increased from 2016 to 2018 (39% to 53%, p < 0.01) while use of 30 Gy in 10 fractions decreased (26% to 12%, p < 0.01), and 8 Gy × 1 was stable (5.3% to 6.9%, p = 0.28). SBRT was associated with higher performance status (p < 0.01) and non-radiosensitive histology (p < 0.01). Use of SBRT increased in the regional network (19% to 48%, p < 0.01) and at the main center (52% to 59%, p = 0.02), but did not increase within 30 days of death. More patients treated with 8 Gy × 1 than SBRT died within 30 days of treatment (24% vs 3.8%, respectively, p < 0.01). CONCLUSIONS:SBRT is replacing 30 Gy in 10 fractions for bone metastases, especially among patients with high performance status and non-radiosensitive histologies. Better prognostic algorithms could further improve patient-centered treatment selection at the end of life.

PURPOSE/OBJECTIVE:Telemedicine was rapidly implemented for initial consultations and radiation treatment planning in the wake of the coronavirus disease 2019 (COVID-19) pandemic. In this study, we explore utilization of and physician perspectives on this approach in an attempt to identify patient populations that may benefit most from virtual care. METHODS AND MATERIALS/METHODS:This is a mixed-methods study with a convergent design. Approximately 6 to 8 weeks after implementation of telemedicine, all radiation oncologists in a single academic radiation oncology department were invited to participate in either semistructured interviews with embedded survey questions or a concurrently administered survey only. Rapid qualitative analysis was used to identify common themes, and quantitative data was assessed using descriptive statistics and univariable analyses. RESULTS:At the apex of the pandemic, 92% of radiation oncology visits were conducted via telemedicine. In total, 51 of 61 radiation oncologists participated in the study (response rate 84%). Most (71%) reported no difference in ability to treat cancer appropriately via telemedicine, which was more common among specialized physicians (P = .01) but not those with higher visit volume or years of experience. Over half (55%) perceived no difference or even improvement in overall visit quality with telemedicine. Virtual visits were deemed acceptable for a median of 70% to 96% of patients, which varied by disease site. Need for physical examination, and availability of an acceptable proxy, factored into telemedicine acceptability. Most (88%) found telemedicine better than expected, but opinions were split on how telemedicine would affect physician burnout. Almost all (96%) foresaw a role for telemedicine beyond the pandemic and would opt for a median of 50% (interquartile range 20%-66%) of visits conducted via telemedicine. CONCLUSIONS:Among radiation oncologists in an academic setting, telemedicine was perceived to be highly appropriate and acceptable for most patients. Future studies should focus on identifying the 5% to 30% of patients whose care may be optimized with in-person visits, and if there is alignment with patient preferences.

PURPOSE/OBJECTIVE:(AirXanpders®, Palo Alto, CA) tissue expander in-situ for breast cancer patients receiving post-mastectomy radiation therapy. METHODS AND MATERIALS/METHODS:A film phantom (P1) was constructed by placing the metallic canister of the AeroForm on a solid water phantom with EBT3 films at five depths ranging from 2.6 mm to 66.2 mm. A breast phantom (P2), a three-dimensional printed tissue-equivalent breast with fully expanded AeroForm in-situ, was placed on a thorax phantom. A total of 21 optical luminescent dosimeters (OLSDs) were placed on the anterior skin-gas interface and the posterior chest wall-metal interface of the AeroForm. Both phantoms were imaged with a 16-bit computed tomography scanner with orthopedic metal artifact reduction. P1 was irradiated with an open field utilizing 6 MV and 15 MV photon beams at 0°, 90°, and 270°. P2 was irradiated using a volumetric modulated arc therapy plan with a 6 MV photon beam and a tangential plan with a 15 MV photon beam. All doses were calculated using Eclipse (Varian, Palo Alto, CA) with AAA and AcurosXB (AXB) algorithms. RESULTS:The average dose differences between film measurements and AXB in the region adjacent to the canister in P1 were within 3.1% for 15 MV and 0.9% for 6 MV. Local dose differences over 10% were also observed. In the chest wall region of P2, the median dose of OLSDs in percentage of prescription dose were 108.4% (range 95.4%-113.0%) for the 15MV tangential plan and 110.4% (range 99.1%-113.8%) for the 6MV volumetric modulated arc therapy plan. In the skin-gas interface, the median dose of the OLSDs were 102.3% (range 92.7%-107.7%) for the 15 MV plan and 108.2% (range 97.8-113.5%) for the 6 MV plan. Measured doses were, in general, higher than calculated doses with AXB calculations. The AAA dose algorithms produced results with slightly larger discrepancies between measurements compared with AXB. CONCLUSIONS:The AeroForm creates significant dose uncertainties in the chest wall-metal interface. The AcurosXB dose calculation algorithm is recommended for more accurate calculations. If possible, post-mastectomy radiation therapy should be delivered after the permanent implant is in place.

PURPOSE/OBJECTIVE:The 2016 American Society for Radiation Oncology consensus guidelines for the use of accelerated partial-breast irradiation (APBI) define "suitable," "cautionary," and "unsuitable" populations for this adjuvant breast radiation therapy technique. We sought to determine whether patients in the cautionary group exhibited adverse outcomes after APBI compared with their suitable counterparts. METHODS AND MATERIALS/METHODS:We identified 252 consecutively treated patients from a single institution with in situ or early-stage invasive breast cancer who underwent APBI between 2008 and 2017. Treatment technique was uniform throughout the population, consisting of 3-dimensional conformal radiation therapy to 40 Gy administered in 10 daily fractions. RESULTS:One hundred seventy-eight patients (70%) were classified as suitable, 69 (27%) as cautionary, and 5 (2.0%) as unsuitable. Because unsuitable patients were few and had no recurrences, they were excluded from analysis. At a median follow-up time of 3.9 years, 97.2% of patients were free of recurrence. Four patients (1.5% overall; 3 suitable and 1 cautionary) experienced ipsilateral in-breast recurrences, and 1 cautionary patient developed an ipsilateral regional recurrence in an axillary lymph node. There was no significant difference in the rate of ipsilateral breast recurrence (2.4% vs 1.0%) between cautionary and suitable groups. CONCLUSIONS:Local recurrences are rare among guideline-defined cautionary patients with in situ or invasive breast cancer treated with APBI delivered via daily 3-dimensional conformal radiation therapy to 40 Gy. At a median follow-up of 3.9 years, no significant differences in local control were noted between cautionary and suitable patient groups. Further study is needed to characterize long-term disease outcomes among various risk groups.

PURPOSE:To evaluate physician-reported assessments of an established faculty orientation program for new radiation oncology physicians at a large academic center and to prospectively analyze the effects of an onboarding improvement program based on those assessments. MATERIALS AND METHODS:An anonymous survey was designed and distributed to physicians new to the department who received onboarding orientation between 2013 and 2017. Survey questions addressed the comprehensiveness, effectiveness, and utility of various orientation activities. On the basis of the survey results, an improved onboarding program was designed and implemented for nine new faculty members between May 2018 and November 2018. A post-intervention survey querying topics similar to those in the pre-intervention survey was distributed to the new faculty members. Descriptive statistics were generated to compare the pre-intervention and post-intervention groups. RESULTS:The overall rate of survey completion was 85% (17 of 20). The intervention program markedly improved physician assessment of comprehensiveness and effectiveness of the onboarding process. Physicians strongly and consistently identified mentor shadowing, on-the-job training, and other faculty mentorship activities as the most important components of an effective onboarding experience. CONCLUSION:An enhanced, tailored, person-oriented, formal onboarding improvement program significantly increased physician assessment scores of comprehensiveness and effectiveness of the faculty onboarding process. This model can serve as a framework for increasing physician preparedness, encouraging early physician mentorship, and ensuring a universal standard of quality across large practices.

PURPOSE/OBJECTIVE:Cosmetic outcomes and rate of implant loss are poorly characterized among patients with breast cancer with previous breast augmentation (BA) who undergo breast-conservation therapy (BCT). Here we determine capsular contracture and implant loss frequency after BCT among patients receiving contemporary whole-breast radiation therapy (RT). METHODS AND MATERIALS/METHODS:Patients with breast cancer with a history of BA presenting to our institution from January 2006 to January 2017 who elected for BCT were included. Seventy-one breast cancers in 70 patients with a history of BA electing for BCT were retrospectively identified. Clinicopathologic, treatment, and outcome variables were examined. Whole-breast RT included conventional and hypofractionated schedules with and without a boost. Rates of implant loss and cosmetic outcomes among patients who did and did not develop a new/worse contracture based on physician assessment were compared. RESULTS:In the study, 54.9% of patients received radiation using hypofractionated whole-breast tangents; 81.7% received a boost. In addition, 18 out of 71 cases (25.4%) developed a new/worse contracture after BCT with a mean follow-up of 1.9 years. Furthermore, 9 out of 71 cases (12.7%) were referred to a plastic surgeon for revisional surgery. There were no implant-loss cases. On univariate analysis, implant location, time from implant placement to diagnosis, RT type, RT boost, body mass index, and tumor size were not associated with new/worse contracture. Of 12 patients with existing contracture, only 2 developed worsening contracture. Physician assessment of cosmetic outcome after BCT was noted to be excellent or good for 87.4% of patients. CONCLUSIONS:BCT for breast cancer patients with prior history of BA has a low risk of implant loss. Hypofractionated RT does not adversely affect implant outcomes. Patients should be counseled regarding risk for capsular contracture, but the majority have good/excellent outcome; BA does not represent a contraindication to BCT.

Importance/UNASSIGNED:Regional nodal irradiation (RNI) for node-positive breast cancer reduces distant metastases and improves survival, albeit with limited reduction in regional nodal recurrences. The mechanism by which RNI robustly reduces distant metastases while modestly influencing nodal recurrences (ie, the presumed target of RNI) remains unclear. Objective/UNASSIGNED:To determine whether some distant metastases putatively arise from occult regional nodal disease and whether regional recurrences otherwise remain largely undetected until an advanced cancer presentation. Design, Setting, and Participants/UNASSIGNED:This cohort study examined patients presenting with de novo stage IV breast cancer to the Memorial Sloan Kettering Cancer Center in New York, New York, from 2006 to 2018. Medical records were reviewed to ascertain clinicopathological parameters, including estrogen receptor status and survival. Pretreatment positron emission tomography-computed tomography (PET-CT) imaging was reviewed to ascertain the extent of regional nodal involvement at metastatic diagnosis using standard nodal assessment criteria. A subset underwent regional lymph node biopsy for diagnostic confirmation and served to validate the radiographic nodal assessment. Data analysis was performed from October 2019 to February 2020. Exposures/UNASSIGNED:Untreated metastatic breast cancer. Main Outcome and Measures/UNASSIGNED:The primary outcome was the likelihood of regional nodal involvement at the time of metastatic breast cancer presentation and was determined by reviewing pretreatment PET-CT imaging and lymph node biopsy findings. Results/UNASSIGNED:Among 597 women (median [interquartile range] age, 53 [44-65] years) with untreated metastatic breast cancer, 512 (85.8%) exhibited regional lymph node involvement by PET-CT or nodal biopsy, 509 (85%) had involvement of axillary level I, 328 (55%) had involvement in axillary level II, 136 (23%) had involvement in axillary level III, 101 (17%) had involvement in the supraclavicular fossa, and 96 (16%) had involvement in the internal mammary chain. Lymph node involvement was more prevalent among estrogen receptor-negative tumors (92.4%) than estrogen receptor-positive tumors (83.6%). Nodal involvement at the time of metastatic diagnosis was not associated with overall survival. Conclusions and Relevance/UNASSIGNED:These findings suggest that a majority of patients with de novo metastatic breast cancer harbor regional lymph node disease at presentation, consistent with the hypothesis that regional involvement may precede metastatic dissemination. This is in alignment with the findings of landmark trials suggesting that RNI reduces distant recurrences. It is possible that this distant effect of RNI may act via eradication of occult regional disease prior to systemic seeding. The challenges inherent in detecting isolated nodal disease (which is typically asymptomatic) may account for the more modest observed benefit of RNI on regional recurrences. Alternative explanations of nodal involvement that arises concurrently or after metastatic dissemination remain possible, but do not otherwise explain the association of RNI with distant recurrence.

BACKGROUND:Postmastectomy proton radiotherapy improves normal tissue sparing in comparison to photon-based approaches. Several studies have reported dosimetry comparison and tolerable acute toxicity profile with limited follow-up. We report our institutional experience of postmastectomy proton radiation including clinical efficacy and toxicities. METHODS:From December 2013 to February 2015, 42 consecutive patients who received mastectomy for non-metastatic breast cancer were treated with adjuvant chest wall and regional nodal proton therapy at a single proton center. 3D conformal uniform scanning with en face matching fields was used. RESULTS:The median follow-up among patients was 35 months (range 1-55 months). There was one local failure, zero regional nodal failure, and six distant failures. The 3-year rate of locoregional disease-free survival was 96.3%, metastasis-free survival was 84.1%, and overall survival was 97.2%. The only local failure event occurred on the chest wall within the radiation field, approximately 2.5 years after the completion of radiation. Skin dermatitis, fatigue, and esophagitis were the most common acute toxicity. All patients developed grade 1 or 2 acute skin toxicity and there was no grade 3 or 4 acute skin toxicity. Proton radiation is able to achieve excellent target coverage with median PTV V95 over 95% and heart sparing with median mean heart dose less than 1 Gy (RBE). CONCLUSION:With close to three years of median follow-up, post-mastectomy proton radiation has shown excellent locoregional control rates and favorable toxicity profile. Long-term adverse effect of heart-sparing radiation will require longer follow-up time and randomized clinical trials.