Dose-response model for severe late laryngeal toxicity after stereotactic body radiation therapy for previously-irradiated head and neck cancer.

We sought to evaluate the association between larynx dose and risk of severe late laryngeal toxicity in patients undergoing re-irradiation SBRT for recurrent HNC. Fifty-five patients with an intact larynx underwent re-irradiation SBRT to a median dose of 44 Gy in 5 fractions. Five (41.7%) patients treated for a laryngeal/hypopharyngeal recurrence experienced late grade ≥3 laryngeal toxicity, compared to 0.0-7.1% for other sites. Logistic dose-response models were created to predict risk of severe late laryngeal toxicity, including dysphagia and airway compromise. According to the model, the risk of severe laryngeal toxicity with a larynx D5cc of 5 Gy is 5.8% (95% CI 2.9-9.9%) and rises to 11.4% with a D5cc of 20 Gy and 25.3% with a D5cc of 40 Gy. In patients with a laryngeal/hypopharyngeal recurrence, SBRT planning should carefully assess the dose to laryngeal structures given these dose findings, and SBRT should be approached with significant caution in such patients.

Dose-response modeling the risk of carotid bleeding events after stereotactic body radiation therapy for previously irradiated head and neck cancer.

Given the lack of clear dose constraints for the carotid artery, we created dose-response models to better quantify the risk of carotid bleeding events following re-irradiation stereotactic body radiation therapy (SBRT) for head and neck cancer (HNC). We performed a retrospective analysis on 75 patients treated with SBRT for recurrent, previously irradiated HNC. Logistic dose-response models were created to predict the risk of a carotid bleeding event, defined as any mucosal bleeding event or bleeding resulting from rupture of the carotid artery or its major branches in the setting of controlled disease. According to the models, the risk of a carotid bleeding event with a cumulative D0.1cc of 20 Gy from SBRT is 0.8% (95% CI 0.1%-3.9%), and rises to 5.0% with a D0.1cc of 50 Gy. No patient experienced a carotid bleeding event with D0.1cc < 39.4 Gy, and none experienced carotid blowout syndrome with a cumulative D0.1cc < 47.6 Gy.

Magnetic resonance imaging response in patients treated with definitive radiation therapy for medically inoperable endometrial cancer-Does it predict treatment response?

PURPOSE: Many patients with endometrial cancer cannot undergo surgery and instead receive definitive radiation therapy (RT). We investigate the correlation between MRI response to RT and clinical outcomes. METHODS AND MATERIALS: Women with inoperable, clinical Stage I endometrial cancer were treated with definitive brachytherapy (BT) with/without pelvic RT (PRT). Patients underwent MRI with functional diffusion-weighted imaging before and after RT. A radiologist retrospectively classified cases as complete, partial, or indeterminate response (CR, PR, or IR, respectively) vs. disease progression. Local control was clinicopathologically defined. RESULTS: From 2007 to 2017, 50 women underwent definitive RT. Thirty-five (70%) received BT alone (median dose 37.5 Gy). For combined therapy, the median PRT and BT doses were 45 and 25 Gy, respectively. Median gross tumor volume and high-risk clinical target volume were 7.1 cc and 90.0 cc, respectively. Median followup among living patients was 20 months. All patients underwent post-RT MRI with T1/T2 sequencing at a median of 3.2 months after RT; 40 patients (80%) underwent functional diffusion-weighted imaging sequences. On initial post-RT MRI, CR was documented in 42 patients (84%), IR in 1 patient (2%), and PR in seven patients (14%). At median followup of 16.3 months, no CR patients had uterine failure. Among eight patients with initial PR/IR, all were found to be clinicopathologically no evidence of disease at the uterus on further evaluation. CONCLUSIONS: Definitive RT with BT or BT + PRT is associated with high response rates on MRI. Overall, initial CR predicted for excellent outcome with no infield failure.

Is completion axillary lymph node dissection necessary in patients who are underrepresented in the ACOSOG Z0011 trial?

PURPOSE: The American College of Surgeons Oncology Group trial Z0011 demonstrated that axillary node dissection (ALND) can be omitted in patients managed with breast conserving surgery and 1 to 2 positive sentinel lymph nodes (SLNs) without adverse effects on locoregional recurrence or disease-free survival (DFS). We investigated patients with breast cancer for whom clinicopathologic features were underrepresented in the Z0011 trial and analyzed radiation therapy treatment patterns and clinical outcomes. METHODS AND MATERIALS: We retrospectively reviewed records of patients who underwent a lumpectomy and SLN biopsy with positive SLNs but not an ALND and completed adjuvant radiation therapy. Eligible patients had T3 tumors, >2 positive SLNs, invasive lobular carcinoma, estrogen receptor negative status, extranodal extension, Nottingham Grade 3, or were age <50 years. RESULTS: We identified 105 women treated between July 2011 and July 2016 with a median follow-up time of 48.5 months (Range, 11-83 months). There were 40 women with an extranodal extension (38.9%) and 42 women with grade 3 disease (40.0%). Nineteen patients received whole breast irradiation alone (18.1%) and 86 patients were treated with modified tangent fields including the superior axilla level I/II (81.9%). Thirty-three patients (31.4%) also received a 3rd supraclavicular, nodal-directed field. Among the 86 patients who received axillary nodal irradiation, nodal volume contouring was performed in 77 patients (89.5%). Fifty-one patients (48.6%) also received adjuvant chemotherapy. The overall rates of 4-year DFS and locoregional control (LRC) were 94.3% and 98.1%, respectively. Off all patients, 1 patient experienced an internal mammary nodal recurrence, another patient a contralateral breast tumor, and two patients distant metastases. There were no axillary or ipsilateral breast tumor recurrences. CONCLUSIONS: This retrospective analysis of women who were underrepresented or excluded from the Z11 trial and underwent a lumpectomy and SLN biopsy with positive SLNs demonstrated comparable rates of LRC and DFS. The high rates of LRC and DFS suggest that completion ALND may be safely omitted in this patient population but larger data sets and longer follow-up times are needed to confirm this finding.

Image-based multichannel vaginal cylinder brachytherapy for the definitive treatment of gynecologic malignancies in the vagina.

PURPOSE: Brachytherapy is integral to vaginal cancer treatment and is typically delivered using an intracavitary single-channel vaginal cylinder (SCVC) or an interstitial brachytherapy (ISBT) applicator. Multi-channel vaginal cylinder (MCVC) applicators allow for improved organ-at-risk (OAR) sparing compared to SCVC while maintaining target coverage. We present clinical outcomes of patients treated with image-based high dose-rate (HDR) brachytherapy using a MCVC. METHODS AND MATERIALS: Sixty patients with vaginal cancer (27% primary vaginal and 73% recurrence from other primaries) were treated with combination external beam radiotherapy (EBRT) and image-based HDR brachytherapy utilizing a MCVC if residual disease thickness was 7 mm or less after EBRT. All pts received 3D image-based BT to a total equivalent dose of 70-80 Gy. RESULTS: The median high-risk clinical target volume was 24.4 cm3 (interquartile range [IQR], 14.1), with a median dose to 90% of 77.2 Gy (IQR, 2.8). After a median follow-up of 45 months (range, 11-78), the 4-year local-regional control, distant control, DFS, and OS rates were 92.6%, 76.1%, 64.0%, and 67.2%, respectively. The 4-year LRC rates were similar between the primary vaginal (92%) and recurrent (93%) groups (p = 0.290). Pts with lymph node positive disease had a lower rate of distant control at 4 years (22.7% vs. 89.0%, p < 0.001). There were no Grade 3 or higher acute complications. The 4-year rate of late Grade 3 or higher toxicity was 2.7%. CONCLUSIONS: Clinical outcomes of pts with primary and recurrent vaginal cancer treated definitively in a systematic manner with combination EBRT with image-guided HDR BT utilizing a MCVC applicator demonstrate high rates of local control and low rates of severe morbidity. The MCVC technique allows interstitial implantation to be avoided in select pts with ≤7 mm residual disease thickness following EBRT while maintaining excellent clinical outcomes with extended 4-year follow-up in this rare malignancy.

Carotid Dosimetry and the Risk of Carotid Blowout Syndrome After Reirradiation With Head and Neck Stereotactic Body Radiation Therapy.

PURPOSE: To correlate carotid dose and risk of carotid blowout syndrome (CBOS) after stereotactic body radiation therapy (SBRT), hypothesizing that carotid dose does not correlate with CBOS. METHODS AND MATERIALS: We retrospectively reviewed 186 patients with recurrent, previously irradiated head and neck cancer treated between January 2008 and March 2013. Patients treated early in our experience with incomplete dosimetry were excluded from analysis (n = 111). A total of 75 patients were identified, providing 150 carotid arteries for analysis. Median follow-up was 8 months (range, 1-91 months) for all patients, and 37 months for surviving patients (range, 31-91 months). Patients were treated with linear accelerator-based SBRT to a median dose up to 44 Gy (range, 40-50 Gy) in 5 fractions delivered on a twice-weekly basis. Concurrent cetuximab was used in 63 patients (84%). The bilateral common, internal, and external carotid arteries were delineated 2 cm above and below the planning target volume. The maximum dose to 0.1 cm3 (D0.1cc), 1 cm3 (D1cc), and 2 cm3 (D2cc) of the carotid and the mean carotid dose from SBRT were recorded and analyzed for association with carotid bleeding events, using binary logistic regression. RESULTS: Median reirradiation interval was 20 months (range, 3-423 months), and median prior radiation dose was 70 Gy (range, 52.5-140 Gy). Sixteen patients (21.3%) received more than 1 course of SBRT, and the cumulative carotid doses from fused summary plans were recorded. The overall median D0.1cc, D1cc, D2cc, and mean carotid doses were 40.8 Gy (interquartile range [IQR], 21.6-47.6 Gy), 26.8 Gy (IQR, 14.1-42.1 Gy), 15.4 Gy (IQR, 8.4-32.7 Gy), and 15.0 Gy (IQR, 8.9-23.3 Gy), respectively. There were a total of 4 bleeding events (5.3%): 2 patients (2.7%) had mucosal bleeds that resolved after embolization of carotid branches, and 2 patients (2.7%) died from complications of CBOS. In the 2 patients with CBOS the D0.1cc was 48.4 Gy and 47.6 Gy, respectively. There was no significant association between bleeding events and D1cc (P = .280), D2cc (P = .571), or mean dose (P = .568). There was a trend toward increased risk of bleeding and D0.1cc (P = .080). CONCLUSIONS: These results demonstrate a low risk of bleeding after reirradiation with SBRT when 5 fractions are delivered on nonconsecutive days, even when tumor is completely encasing the carotid artery. Although limited by the low number of events, no significant association was found between dose-volume parameters and the risk of carotid bleeding. No CBOS was noted when D0.1cc was <47.6 Gy.

Single-institutional outcomes of adjuvant brachytherapy for Stage I endometrial cancer-Are outcomes consistent with randomized studies?

PURPOSE: Vaginal brachytherapy (VBT) alone has been shown to be a viable adjuvant treatment strategy for most patients with Stage I endometrioid endometrial cancer. We sought to examine our institutional data following practice pattern changes resulting from the publications of GOG-99 and PORTEC-2. METHODS AND MATERIALS: We retrospectively analyzed women who underwent adjuvant VBT after surgical staging for Stage 1 endometrioid endometrial cancer at our institution from 2007 to 2014. RESULTS: We identified 297 women. Median time to last followup or death was 52.3 months (interquartile range: 32.3-72.3 months). By International Federation of Gynecology and Obstetrics 2009 staging, 162 patients (54.5%) had Stage IA and 128 (43.1%) had Stage IB disease. Ninety-nine (33.3%) patients had Grade 1, 153 (51.5%) had Grade 2, and 45 (15.2%) had Grade 3 disease. According to GOG-249 and PORTEC-2 criteria, 167 (56.2%) and 127 (42.7%) patients were with high-intermediate-risk disease. Two women had Stage IB Grade 3 disease. The most common high-dose-rate-VBT regimen was 2100 cGy/three fractions to a depth of 5 mm. Four (two acute and two late) (1.3%) Grade 3 genitourinary toxicities were reported: three episodes of vaginal dehiscence (after second course of VBT, 2 months after completion of VBT, and 1 year after completion of VBT) and one episode of radiation necrosis. Twenty-one (7%) women recurred: three recurred in the vagina, two recurred in the pelvic lymph nodes, and 16 recurred distantly. CONCLUSIONS: Outcomes appear consistent with published randomized data in women with high-intermediate-risk endometrial cancer who are treated with brachytherapy alone. Recurrence and complication rates were minimal.

Concurrent Chemoradiotherapy in the Adjuvant Treatment of High-risk Primary Salivary Gland Malignancies.

OBJECTIVES: Adjuvant radiation therapy (RT) is indicated for patients with salivary gland malignancies with risk factors for recurrence following resection. We analyzed patients treated with adjuvant RT with or without concurrent chemotherapy to determine the impact of prognostic and treatment factors. MATERIALS AND METHODS: Retrospective analysis was performed of 128 patients treated with surgical resection followed by intensity-modulated radiotherapy. In total, 31 (24.2%) patients were treated with concurrent chemoradiotherapy. The Kaplan-Meier method was used to estimate rates of progression-free survival (PFS), local-regional control, distant control, overall survival. Multivariable Cox regression was performed to evaluate factors significant on univariate analysis. RESULTS: The 5-year rates of PFS, local-regional control, freedom-from distant metastasis, and overall survival were 61.2%, 85.8%, 76.5%, and 73.7%, respectively. Predictors of decreased PFS on univariate analyses were age, tumor stage, nodal stage, positive surgical margins, histology, high grade, perineural invasion, lymphovascular space invasion, extranodal extension, and use of chemoradiotherapy. On multivariable analysis, elevated T-stage, positive surgical margins, and presence of extranodal extension were predictive of decreased PFS. The acute toxicity rates were 30.3% grade 1, 51.5% grade 2, 11.4% grade 3, and 0.8% grade 4. There was no difference in rates of grade 3 or higher acute toxicity with use of RT alone versus chemoradiotherapy (P=0.183). CONCLUSIONS: Use of chemoradiotherapy for adjuvant treatment of salivary gland malignancies was well-tolerated, but no improvement in survival was seen with the use of chemoradiotherapy in both the overall study population and a subset with high-risk features. Caution should be used when using this modality until randomized evidence becomes available.

Standardization of nodal radiation therapy through changes to a breast cancer clinical pathway throughout a large, integrated cancer center network.

BACKGROUND: Studies demonstrate safety of omitting axillary nodal dissection for early-stage breast cancer with positive sentinel lymph node (+SLN) biopsy, although trial designs differed in radiation therapy (RT) fields. Regional nodal irradiation was separately shown to improve outcomes in high-risk patients. This led to lack of consensus in RT volumes. Clinical pathways (CPs) standardize care where practice varies unnecessarily. We evaluated the impact of changes to a CP guiding postoperative RT in women with +SLNs on practice patterns throughout a network. METHODS AND MATERIALS: We implemented a CP for management of breast cancer with postoperative RT designed to promote uniform nodal treatment. The CP recommended modified tangents (MTs) including level I/II nodes for women with micrometastases (pN1mi). For women with macrometastases (pN1a), CPs recommended including level I/II LN in MT and a third supraclavicular node (SCN) LN ± internal mammary nodes for women with adverse factors present. RESULTS: RT fields of 233 women undergoing breast-conserving surgery with +SLN but not axillary nodal dissection were retrospectively reviewed: 25% had pN1mi disease and 75% pN1a. Of 127 women treated before CP changes, 35% with pN1mi and 22% with pN1a were treated with whole-breast irradiation alone. Following CP changes, 106 women were treated: 5% with whole-breast irradiation alone, 58% with MT, and 38% with MT + SCN field. Utilization of MT was associated with CP changes. Utilization of a third SCN field was associated with CP changes, pN stage, extracapsular extension, and total number of adverse factors. CONCLUSIONS: CPs translate published data and institutional experience into management plans that promote evidence-based care and eliminate unnecessary practice variations. Recognizing that postoperative RT treatment volumes were heterogeneous, we modified the CP based upon the latest evidence for regional nodal irradiation, after which we found increased compliance and consistency with quality guidelines, which will also aid in tracking outcomes in future investigations.

Standardization of radiation therapy dose for locally advanced non-small cell lung cancer through changes to a lung cancer clinical pathway in a large, integrated comprehensive cancer center network.

PURPOSE: The results of Radiation Therapy Oncology Group (RTOG) 0617, which randomized patients with stages IIIA/IIIB non-small cell lung cancer (NSCLC) to definitive chemoradiation therapy to 60 Gy versus 74 Gy, demonstrated a detrimental survival impact with high-dose radiation therapy. We evaluated the impact of changes to a provider-driven clinical pathway (CP) guiding management of NSCLC on practice throughout our cancer center network. METHODS AND MATERIALS: In 2001, we implemented a CP for management of stage IIIA/IIIB NSCLC with definitive chemoradiation therapy. In 2013, the CP for NSCLC was amended (amendment 1) to allow a dose range of 60 to 74 Gy. The CP was amended (amendment 2) in January 2016 to specify a dose range of 60 to 70 Gy. Higher doses were considered off-pathway and subject to peer review. Data from decisions entered from 2012 to 2016 were obtained. RESULTS: From 2012 until publication of RTOG 0617 in February 2015, the median prescription dose was 66 Gy delivered in 1.8 to 2.1 Gy fractions. Doses ≤66 Gy were prescribed for 52% of patients. From February 2015 to September 2016, the median prescription dose was 60 Gy, and 91% of prescription doses were ≤66 Gy. After amendment 2, 99% of decisions were ≤66 Gy. Dose ≤66 Gy was associated with treatment following publication of 0617 (P < .001) and treatment after amendment 2 (P < .001). On multivariable analysis, treatment after amendment 2 was associated with dose ≤66 Gy (odds ratio, 9.9; 95% confidence interval, 5.2-19.0; P < .001). The percentage of lung receiving 20 Gy was lower following publication of 0617 (P < .001). There was no difference in the percentage of heart receiving 40 Gy. CONCLUSIONS: CPs eliminate variations in practice that lead to inferior outcomes. Recognizing that our CP for definitive treatment of patients with locally advanced NSCLC allowed heterogeneous dose prescriptions, we modified the CP based on the publication of RTOG 0617. We found that the CP was a tool to ensure patients receive evidence-based care across a large cancer center network.

A peer review process as part of the implementation of clinical pathways in radiation oncology: Does it improve compliance?

PURPOSE: Clinical pathways are patient management plans that standardize evidence-based practices to ensure high-quality and cost-effective medical care. Implementation of a pathway is a collaborative process in our network, requiring the active involvement of physicians. This approach promotes acceptance of pathway recommendations, although a peer review process is necessary to ensure compliance and to capture and approve off-pathway selections. We investigated the peer review process and factors associated with time to completion of peer review. METHODS AND MATERIALS: Our cancer center implemented radiation oncology pathways for every disease site throughout a large, integrated network. Recommendations are written based upon national guidelines, published literature, and institutional experience with evidence evaluated hierarchically in order of efficacy, toxicity, and then cost. Physicians enter decisions into an online, menu-driven decision support tool that integrates with medical records. Data were collected from the support tool and included the rate of on- and off-pathway selections, peer review decisions performed by disease site directors, and time to complete peer review. RESULTS: A total of 6965 treatment decisions were entered in 2015, and 605 (8.7%) were made off-pathway and were subject to peer review. The median time to peer review decision was 2 days (interquartile range, 0.2-6.8). Factors associated with time to peer review decision >48 hours on univariate analysis include disease site (P < .0001) with a trend toward significance (P = .066) for radiation therapy modality. There was no difference between recurrent and non-recurrent disease (P = .267). Multivariable analysis revealed disease site was associated with time to peer review (P < .001), with lymphoma and skin/sarcoma most strongly influencing decision time >48 hours. CONCLUSIONS: Clinical pathways are an integral tool for standardizing evidence-based care throughout our large, integrated network, with 91.3% of all treatment decisions being made as per pathway. The peer review process was feasible, with <1% selections ultimately rejected, suggesting that awareness of peer review of treatment decisions encourages compliance with clinical pathway recommendations.

Impact of dynamic changes to a bone metastases pathway in a large, integrated, National Cancer Institute-designated comprehensive cancer center network.

PURPOSE: Studies suggest equivalent pain relief from bone metastases after radiation therapy with >10-fraction regimens and shorter courses. Although American Society for Radiation Oncology evidence-based guidelines and the Choosing Wisely campaign endorse single-fraction treatments and caution against the use of extended courses, publications report single-fraction utilization rates below 5%. We evaluated the impact of our bone metastasis clinical pathway on the adoption of short-course palliative radiation in a large, integrated radiation oncology network. METHODS AND MATERIALS: We implemented a clinical pathway for the management of bone metastases in 2003 that required the entry of management decisions into an online tool that subjected off-pathway choices to peer review beginning in 2009. In 2014, the pathway was modified to encourage single-fraction treatments, and the use of >10 fractions was considered off pathway. Data were obtained from 16 integrated sites (4 academic, 12 community) from 2003 through 2014. Multivariate logistic regression was conducted to establish factors associated with treatment with a single fraction and with >10 fractions. RESULTS: In this study, 12,678 unique courses were delivered. From 2003 to 2008, the single-fraction utilization rate was 7.6%. This increased to 10.9% from 2009 to 2013 and to 15.8% in 2014. The odds ratios for single-fraction use were 1.59 (95% confidence interval [CI], 1.39-1.81) and 2.58 (95% CI, 2.11-3.15) for 2009-2013 and 2014, respectively. Academic physicians were more likely to treat with a single fraction (odds ratio, 5.00; 95% CI, 4.38-5.71). Use of >10-fraction regimens significantly decreased from 18.6% in 2003-2008 to 15.2% in 2009-2013 and 9.7% in 2014. CONCLUSIONS: Although our single-fraction utilization rate was initially in line with national rates (7.6%), the adoption rate increased to >15%. The use of >10-fraction regimens decreased significantly, predominantly among community practices. By 2014, >90% of courses were delivered with <10 fractions. This study demonstrates that provider-driven clinical pathways are able to standardize practice patterns and promote change consistent with evidence-based guidelines.

Patterns of failure for glioblastoma multiforme following limited-margin radiation and concurrent temozolomide.

BACKGROUND: To analyze patterns of failure in patients with glioblastoma multiforme (GBM) treated with limited-margin radiation therapy and concurrent temozolomide. We hypothesize that patients treated with margins in accordance with Adult Brain Tumor Consortium guidelines (ABTC) will demonstrate patterns of failure consistent with previous series of patients treated with 2-3 cm margins. METHODS: A retrospective review was performed of patients treated at the University of Alabama at Birmingham for GBM between 2000 and 2011. Ninety-five patients with biopsy-proven disease and documented disease progression after treatment were analyzed. The initial planning target volume includes the T1-enhancing tumor and surrounding edema plus a 1 cm margin. The boost planning target volume includes the T1-enhancing tumor plus a 1 cm margin. The tumors were classified as in-field, marginal, or distant if greater than 80%, 20-80%, or less than 20% of the recurrent volume fell within the 95% isodose line, respectively. RESULTS: The median progression-free survival from the time of diagnosis to documented failure was 8 months (range 3-46). Of the 95 documented recurrences, 77 patients (81%) had an in-field component of treatment failure, 6 (6%) had a marginal component, and 27 (28%) had a distant component. Sixty-three patients (66%) demonstrated in-field only recurrence. CONCLUSIONS: The low rate of marginal recurrence suggests that wider margins would have little impact on the pattern of failure, validating the use of limited margins in accordance ABTC guidelines.

Impact of radiation treatment parameters and adjuvant systemic therapy on cosmetic outcomes after accelerated partial breast irradiation using 3-dimensional conformal radiation therapy technique.

PURPOSE: There are concerns regarding cosmetic outcomes of 3-dimensional conformal accelerated partial breast radiation therapy (3DCRT APBI). Associations between cosmetic outcomes and treatment parameters or receipt of adjuvant systemic therapy were sought to guide 3DCRT APBI. METHODS AND MATERIALS: An analysis of cosmetic outcomes among patients treated with 3DCRT APBI at Moffitt Cancer Center was performed. Overall cosmesis was evaluated using modified Harvard criteria and toxicity outcomes were graded using National Cancer Institute Common Terminology Criteria for Adverse Events, version 3.0. Patients were treated to 38.5 Gy in 3.85 Gy twice daily fractions per dose-volume objectives specified in the National Surgical Adjuvant Breast and Bowel B-39/Radiation Therapy Oncology Group 0413 (NSABP B-39/RTOG 0413) trial. RESULTS: At least 1 evaluation was available for 97 treated breasts (94 women) with median follow-up of 17.2 months (range, 1-60 months). Most breasts (90.7%) had grade 1 to 2 (excellent to good) overall cosmesis. Nine breasts (9.3%) had grade 3 to 4 (fair to poor) overall cosmesis, secondary to >25% asymmetry in 5 patients, grade 3 fibrosis in 3 patients, and fat necrosis in 1 patient. Increasing percentage of ipsilateral breast volume receiving more than 50% of the prescription dose (V50%) correlated with less than excellent cosmesis (P < .001), with a threshold V50% of 40%. Telangiectasia formation (6%) correlated with increased evaluation planning target volume (P = .006) and V50% (P = .017). Grade 2+ fibrosis (18%) and grade 1+ induration (83%) were also correlated with increasing V50% (P = .006 and .002, respectively). Smaller ipsilateral breast volume correlated with worsening cosmesis (P = .048) and induration (P = .028). Two of 4 patients receiving chemotherapy developed grade 3 fibrosis (P = .004) and fair/poor cosmesis (P = .04). CONCLUSIONS: The current analysis implies that acceptable cosmetic results are achievable with 3DCRT APBI technique by adhering to optimal radiation therapy dose-volume constraints, particularly ipsilateral breast V50%.

Radiotherapy alone or combined with chemotherapy for the treatment of squamous cell carcinoma of the base of the tongue.

OBJECTIVES: To evaluate the efficacy of definitive radiotherapy (RT) for the treatment of base of the tongue cancer in a private practice. METHODS: We retrospectively reviewed the medical records of 48 patients with squamous cell carcinoma of the base of the tongue treated with definitive RT and followed from 0.2 to 15.2 years (median, 2.7 y). Follow-up of living patients ranged from 1.5 to 15.2 years (median, 4.9 y). Two thirds of the patients received twice-daily treatment. The median total dose was 74.4 Gy (range, 65 to 76.8 Gy). The median overall treatment time was 45.5 days (range, 36 to 68 d). There were 3 patients (6%) with clinically positive neck nodes who received a neck dissection. Adjuvant chemotherapy was given to 28 patients (58%) with advanced local-regional disease; 1 patient (4%) received induction chemotherapy and 27 patients (96%) received concomitant chemotherapy. Toxicity was graded according to the Common Terminology Criteria for Adverse Events, v3.0. RESULTS: Local control rates by T stage at 5 years were as follows: T1 to T2, 91%; T3, 83%; and T4, 12%. The 5-year rates of local-regional control were as follows: I to II 80%; III, 89%; IVA, 59%; and IVB, 42%. The rates of overall survival at 5 years were as follows: I to II, 67%; III, 56%; IVA, 45%; and IVB, 33%. The 5-year rates of cause-specific survival were as follows: I to II, 67%; III, 76%; IVA, 50%; and IVB, 60%. Seven patients (15%) experienced severe late complications. CONCLUSIONS: Our data reveal that the local-regional control and overall survival rates after definitive RT were comparable with those in the literature. Twice-daily radiation is well tolerated with moderate-late toxicity, which is consistent with the observations of others.