Evaluating compliance with process-related quality metrics and survival in oral cavity squamous cell carcinoma: Multi-institutional oral cavity collaboration study

BACKGROUND

Process-related measures have been proposed as quality metrics in head and neck cancer care. A recent single-institution study identified four key metrics associated with increased survival. This study sought to validate the association of these quality metrics with survival in a multi-institutional cohort.

METHODS

Multicenter retrospective study of patients with oral cavity squamous cell (1/2005-1/2015). Baseline patient and disease characteristics and compliance with quality metrics was evaluated. Association between compliance with quality metrics with overall survival (OS), disease-free survival (DFS), and disease-specific survival (DSS) was evaluated using Cox proportional hazards models.

RESULTS

Failure to comply with two or more of the quality metrics was associated with worse OS, DFS, and DSS. Adherence to all or all but one of the quality metrics was found to be associated with improved survival.

CONCLUSIONS

Process-related quality metrics are associated with increased survival in patients with oral cavity squamous cell carcinoma in a multi-institutional cohort.

Clinical management of emerging sinonasal malignancies

Several emerging sinonasal malignancies have recently been described in the pathology literature. Although not all distinctly classified by the World Health Organization, these rare tumors present a management challenge to surgeons and oncologists. While prior studies have summarized histologic details, a clinically focused review is currently lacking in the literature. This review describes the presentation, histopathology, imaging, treatment, and prognosis of newly described or recently evolving sinonasal malignancies while highlighting the distinguishing features of these entities. It includes teratocarcinosarcoma, human papillomavirus-related multiphenotypic carcinoma, biphenotypic sinonasal sarcoma, sinonasal renal cell-like adenocarcinoma, NUT-midline carcinoma, squamous cell carcinoma associated with inverted papilloma, sinonasal undifferentiated carcinoma, and INI-1-deficient sinonasal carcinoma. By describing the diagnosis, treatment, and prognosis of these recently defined entities, this clinical review aims to help guide oncologists in the clinical management of these patients.

Impact of routine surveillance imaging on detecting recurrence in human papillomavirus associated oropharyngeal cancer

OBJECTIVES

This study examines the utility of surveillance imaging in detecting locoregional failures (LRF), distant failures (DF) and second primary tumors (SPT) in patients with human papillomavirus (HPV) associated oropharyngeal cancer (OPC) after definitive chemoradiotherapy (CRT).

METHODS AND MATERIALS

An institutional database identified 225 patients with biopsy proven, non- metastatic HPV+ OPC treated with definitive CRT between 2004 and 2015, whose initial post-treatment imaging was negative for disease recurrence (DR). Two groups were defined: patients with <2 scans/year Group 1 and patients with ≥2 scans/year Group 2. The Mann-Whitney test or Chi-square was used to determine differences in baseline characteristics between groups. Fine & Gray regression was used to detect an association between imaging frequency, DR and diagnosis of SPT.

RESULTS

Median follow up was 40.8 months. 30% of patients had ≥T3 disease and 90% had ≥ N2 disease (AJCC 7th edition). Twenty one failures (9.3%) were observed, 7 LRF and 15 DF. Six LRF occurred within 24 months and 14 DF occurred within 36 months of treatment completion. Regression analysis showed Group 2 had increased risk of DR compared to Group1 (HR 10.3; p = 0.002) albeit with more advanced disease at baseline. Five SPT were found (2 lung, 2 esophagus, and 1 oropharynx) between 4.5 and 159 months post-CRT.

CONCLUSION

Surveillance imaging seems most useful in the first 2-3 years post treatment, and is particularly important in detecting DF. Surveillance scans for SPT has a low yield, but should be considered for those meeting lung cancer screening guidelines.

Validation of RTOG 0813 Proximal Bronchial Tree Constraints for Pulmonary Toxicity With Stereotactic Body Radiation Therapy for Central Non-small Cell Lung Cancer

PURPOSE

Clinical validation of protocol-specified dosimetric constraints for the proximal bronchial tree (PBT) is limited for central non-small cell lung cancer treated with stereotactic body radiation therapy. We sought to validate Radiation Therapy Oncology Group (RTOG) PBT constraints with a large institutional data set.

METHODS AND MATERIALS

Lesions ≤2 cm from the PBT treated with definitive stereotactic body radiation therapy from 2009 to 2016 were identified from a prospective registry of 1462 patients. Every PBT dose and volume combination, ranging from 0 cGy to 8000 cGy in increments of 10 cGy and volumes ranging from 0.03 cm³ to 50 cm³ in increments of 0.03 cm³, was analyzed. The sensitivity and specificity of these endpoints for identifying pulmonary toxicity were calculated. Pulmonary toxicity was classified as pneumonitis or nonpneumonitis toxicity (NPT) (fistula, stenosis, necrosis, hemoptysis, clinically significant pleural effusion). The optimal dosimetric predictor was chosen by calculation of F-score (highest sensitivity and specificity).

RESULTS

The study included 132 patients, with 26.0-month median follow-up. Eight grade ≥2 NPT (2 grade 5) and 8 grade 2 pneumonitis toxicities were observed. The PBT dosimetric endpoint with the highest F-score for identification of grade 2 to 5 NPT was D0.03cc ≤5000 cGy and that for grade 3 to 5 NPT was D0.33cc ≤4710 cGy, with sensitivity and specificity of 87.5% and 76.6% and 100.0% and 85.7%, respectively. Applying the RTOG 0813 PBT constraints to our data set achieved a sensitivity and specificity of 33.3% and 92.1% for D4cc ≤1800 cGy and 37.5% and 92.7% for D0.03cc ≤5250 cGy for identification of grade 2 to 5 NPT. A PBT dosimetric correlation for pneumonitis toxicity could not be identified.

CONCLUSIONS

This novel dosimetric analysis validates current RTOG constraints and emphasizes high-dose, small-volume constraints as better predictors for NPT. We demonstrated that a slightly lower maximum point dose PBT constraint may be optimal for identification of NPT. Validation of these findings in a larger cohort of patients with longer follow-up is necessary.

Outcomes in intermediate-risk squamous cell carcinomas treated with Mohs micrographic surgery compared with wide local excision

BACKGROUND

Brigham and Women's Hospital stage T2a squamous cell carcinomas, demonstrating a single high-risk feature, have a low risk of metastasis and death but an increased risk of local recurrence. Little evidence exists for the best treatment modality and associated outcomes in T2a squamous cell carcinoma.

OBJECTIVE

We aimed to compare outcomes for T2a squamous cell carcinoma treated by Mohs micrographic surgery compared with wide local excision with permanent sections.

METHODS

Retrospective review of an institutional review board-approved single-institution registry of T2a squamous cell carcinoma.

RESULTS

Three hundred sixty-six primary T2a tumors were identified, including 240 squamous cell carcinomas (65.6%) treated with Mohs micrographic surgery and 126 (34.4%) treated with wide local excision. A total of 32.5% of patients were immunosuppressed and mean oncologic follow-up was 2.8 years. Local recurrence was significantly more likely after wide local excision (4.0%) than after Mohs micrographic surgery (1.2%) (P = .03). Multiple logistic regression demonstrated immunocompromised state (odds ratio [OR] 5.1; 95% confidence interval [CI] 1.1-23.3; P = .03) and wide local excision (OR 4.8; 95% CI 1.1-21.6; P = .04) associated with local recurrence; and wide local excision (OR 7.8; 95% CI 2.4-25.4; P < .001), high-risk head and neck location (OR 8.3; 95% CI 1.8-38.7; P = .004), and poor histologic differentiation (OR 4.7; 95% CI 1.4-15.4; P = .03) associated with poor outcomes (overall recurrence or disease-specific death).

CONCLUSION

Mohs micrographic surgery provides improved outcomes in Brigham and Women's Hospital T2a squamous cell carcinoma.

Tumor Volume Useful Beyond Classic Criteria in Selecting Larynx Cancers For Preservation Therapy

OBJECTIVE

To investigate the association between tumor volume and locoregional failure (LRF) after concurrent chemoradiation (CCRT) for locally advanced larynx cancer (LC).

METHODS

This is a retrospective cohort study from 2009 to 2014 identified from an institutional review board-approved registry. Fifty-nine of 68 patients with locally advanced larynx cancer treated with definitive CCRT who had available imaging for review were identified. The main endpoint to be assessed was the association between gross tumor volumes (GTV; T = total, P = primary, N = nodal) and LRF. Receiver operative characteristic (ROC) curves were used to investigate diagnostic accuracy.

RESULTS

Twenty LRFs were observed, resulting in a 2-year LRF rate of 39% (95% CI, 23-52%). On UVA, the GTV-T (P = .01), GTV-P (P = .05), and GTV-N (P = .04) were statistically significant predictors of LRF. Furthermore, age, smoking status, N-stage, larynx subsite, and tracheostomy/feeding tube dependence were potentially associated with LRF (P < .3), whereas T-stage (T3-4 vs. T2) was not (HR 1.05, 95% CI, 0.38-2.91, P = .92). In the multivariable model, GTV-P (HR 1.022, 95% CI, 0.999-1.046, P = .07) and GTV-N (HR 1.053, 95% CI, 1.0004-1.108, P = .05) were the two most impactful covariates on the model's R² . ROC analysis suggested an optimal cut point of 12 cc in the GTV-T. The 2-year LRF for GTV-T > 12 cc was 64.2% and ≤ 12 cc was 16.4%, P = .006.

CONCLUSION

GTV is associated with LRF after definitive CCRT for LC. Patients with bulky primary and/or nodal tumors may be better served with upfront surgical resection regardless of T-stage. Further investigation into the safety of larynx preservation for low-volume T4 tumors can be considered.

LEVEL OF EVIDENCE

4 Laryngoscope, 130:2372-2377, 2020.

Long-term complications and reconstruction failures in previously radiated breast cancer patients receiving salvage mastectomy with autologous reconstruction or tissue expander/implant-based reconstruction

Salvage mastectomy (SM) is the standard of care for patients with local recurrence (LR) after breast conservation therapy (BCT), often with immediate reconstruction. Complications of reconstruction are a concern for these patients, and long-term data are limited. We sought to compare rates of complications requiring re-operation (CRR) and reconstruction failure (RF) between autologous reconstruction (AR) and tissue expander/implant reconstruction (TE/I). Patients with locally recurrent breast cancer after BCT, treated with SM and immediate AR or TE/I between 2000 and 2008, were identified. CRR was defined as unplanned return to operating room for wound infection, dehiscence, necrosis (including flap, skin, or fat), hematoma, or hernia (for AR) and extrusion, leak, or capsular contracture (for TE/I). RF was defined as conversion to another reconstruction technique or to flat chest wall. This study included 103 patients with 107 reconstructions. Median follow-up was 6.6 years. CRR and RF were significantly higher with TE/I (n = 34) compared to AR (n = 73) at 5 years (50.9% vs 25.5%; P = 0.02) and (42.1% vs 5.8%; P < 0.001). On univariate analysis (UVA), TE/I (HR = 2.14; P = 0.02) and diabetes (HR = 5.10; P = 0.007) were significant predictors for CRR. On UVA, TE/I (HR = 7.30; P < 0.001) and older age at reconstruction (HR = 1.03; P = 0.003) were significant predictors for RF. In this population of previously irradiated patients, TE/I was associated with significantly higher CRR and RF. Complications continue to occur up to 10 years after TE/I. AR should be considered in appropriately selected patients, though TE/I may remain a reasonable option in patients without high-risk factors for surgical complications.

Five-year outcomes of sparing level IB in node-positive, human papillomavirus-associated oropharyngeal carcinoma: A safety and efficacy analysis

INTRODUCTION

The conformality of modern intensity modulated radiation therapy (IMRT) allows avoidance of the submandibular glands (SMG) in select patients, potentially improving late xerostomia. This study explores the safety and efficacy of this approach in select oropharyngeal carcinoma (OPC) patients.

METHODS

Patients with T1-2N+ human papillomavirus (HPV)-associated OPC treated with definitive IMRT at one institution from 2009 to 2014 were identified. Patients were divided into 3 groups: bilateral level IB targeted (A, n = 16), a single level IB targeted (B, n = 61), and bilateral IB spared (C, n = 9). Outcomes were reviewed to identify the rate of level IB regional recurrence. Odds ratios were calculated for xerostomia between groups.

RESULTS

Level Ib was targeted in 93 instances (54.1%) and avoided in 79 instances (45.9%). Mean SMG doses were significantly lower when level IB was spared compared to when targeted (37.5 Gy vs 67.5 Gy; P < 0.0001). Median doses to oral cavity decreased with increasing level Ib sparing (40.7 Gy [A] vs 35.4 Gy [B] vs 30.7 [C]; P = 0.002). The rate of late grade ≥2 xerostomia was significantly lower in patients with bilateral 1b sparing (53% in A vs 0% in C; P = 0.007). Sparing 1b unilaterally resulted in a non-significant decrease in late grade ≥2 xerostomia (P = 0.181). No regional failures were identified in levels IB (median follow up = 59.3 months).

CONCLUSION

Sparing level IB is safe in T1-2N+ HPV+ OPC. Avoiding level Ib translates into significantly lower SMG and oral cavity doses. Larger studies are needed to validate these findings and the impact of this technique.

Correlation between plan quality improvements and reduced acute dysphagia and xerostomia in the definitive treatment of oropharyngeal squamous cell carcinoma

BACKGROUND

To evaluate plan quality using volumetric-modulated arc therapy (VMAT) and step-and-shoot intensity-modulated radiation therapy (SS-IMRT) techniques and for patients treated for oropharyngeal squamous cell carcinoma (OPSCC).

METHODS

Treatment plans for patients treated definitively for stages I-IVb, OPSCC between December 2009 and August 2015 were retrospectively reviewed. Dosimetric endpoints of involved organs-at-risk (OARs) were retrieved from clinical plans. Common Terminology Criteria for Adverse Events scores of acute toxicities were compared.

RESULTS

Two-hundred twenty-two patients were identified with 134 and 88 receiving SS-IMRT and VMAT with median follow-up time of 23.0 and 7.9 months, respectively. The dosimetric endpoints of the OARs were significantly improved in VMAT cohort, which translated into significantly lower rates of grade 2 or higher acute dysphagia and xerostomia.

CONCLUSION

Improvements in stages I-IVb, oropharyngeal cancer plan quality are associated with reduced grade ≥ 2 acute dysphagia and xerostomia.

Selectively sparing the submandibular gland when level Ib lymph nodes are included in the radiation target volume: An initial safety analysis of a novel planning objective

BACKGROUND

Submandibular gland (SMG) metastases are extremely rare in head and neck cancer, even in the presence of level Ib lymph node (LN) involvement. In recent years, we have contoured the SMG and specifically attempted to limit its dose exposure even in patients in whom the level Ib LN station is targeted. This study reports our preliminary feasibility and safety experience with selective submandibular gland sparing.

METHODS

Patients with squamous cell cancer (SCC) of the oral cavity or oropharynx with T1-2, N0-3, M0 disease in whom at least a single level Ib lymph node region was included in the target volume were identified. All patients were treated from 2009 to 2014 with definitive or postoperative IMRT with or without chemotherapy. Patients with recurrent disease, previous radiation or treated palliatively were excluded.

RESULTS

A total of 174 patients met criteria for inclusion. Among the 185 level Ib LN stations that were deliberately targeted in the clinical treatment volume, 32 submandibular glands were contoured, excluded from the target volume and avoided during treatment planning. Mean dose to the spared SMG were reduced by 12% (66.6 Gy vs. 58.9 Gy, p < .001). None of these patients experienced any level 1b LN failures.

CONCLUSION

Selective sparing of the submandibular gland when targeting the level 1b nodes in oral cavity and oropharynx cancer is feasible, reduces the mean dose to submandibular glands and does not result in increased level 1b nodal failure rates. Additional studies with larger cohorts are needed to validate this preliminary observation.

Effect of Tumor Location and Dosimetric Predictors for Chest Wall Toxicity in Single-Fraction Stereotactic Body Radiation Therapy for Stage I Non-Small Cell Lung Cancer

PURPOSE

Dosimetric parameters to limit chest wall toxicity (CWT) are not well defined in single-fraction (SF) stereotactic body radiation therapy (SBRT) phase 2 trials. We sought to determine the relationship of tumor location and dosimetric parameters with CWT for SF-SBRT.

METHODS AND MATERIALS

From a prospective registry of 1462 patients, we identified patients treated with 30 Gy or 34 Gy. Gross tumor volume was measured as abutting, ≤1 cm, 1 to 2 cm, or >2 cm from the chest wall. CWT was prospectively graded according to Common Terminology Criteria for Adverse Events version 3.0, with grade 2 requiring medical therapy, grade 3 requiring procedural intervention, and grade 4 being disabling pain. Grade 1 CWT or radiographic rib fracture was not included. Logistic regression analysis was used to identify the parameters associated with CWT and calculate the probability of CWT with dose.

RESULTS

This study included 146 lesions. The median follow-up time was 23.8 months. The 5-year local control, distant metastasis, and overall survival rates were 91.8%, 19.2%, and 28.7%, respectively. Grade 2 to 4 CWT was 30.6% for lesions abutting the chest wall, 8.2% for ≤1 cm from the chest wall, 3.8% for 1 to 2 cm from the chest wall, and 5.7% for >2 cm from the chest wall. Grade ≥3 CWT was 1.4%. Tumor abutment (odds ratio [OR]: 6.5; P = .0005), body mass index (OR: 1.1; P = .02), rib D1cc (OR: 1.01/Gy; P = .03), chest wall D1cc (OR: 1.08/Gy; P = .03), and chest wall D5cc (OR: 1.10/Gy; P = .01) were significant predictors for CWT on univariate analysis. Tumor abutment was significant for CWT (OR: 7.5; P = .007) on multivariate analysis. The probability of CWT was 15% with chest wall D5cc at 27.2 Gy and rib D1cc at 30.2 Gy.

CONCLUSIONS

The rate of CWT with SF-SBRT is similar to the rates published for fractionated SBRT, with most CWT being low grade. Tumor location relative to the chest wall is not a contraindication to SF-SBRT, but the rates increase significantly with abutment. Rib D1cc and chest wall D1cc and D5cc may be used as predictors of CWT.

Suboptimal Outcomes in Cutaneous Squamous Cell Cancer of the Head and Neck with Nodal Metastases

BACKGROUND/AIM

There are limited data regarding survival, failure patterns, and factors associated with disease recurrence in patients with cutaneous squamous cell cancer of the head and neck (cSCC-HN) with nodal metastases.

PATIENTS AND METHODS

A retrospective analysis of patients with cSCC-HN metastatic to cervical and/or parotid lymph nodes treated with surgery and post-operative radiation therapy was performed.

RESULTS

This study included 76 patients (57 immunocompetent and 18 immunosuppressed) with a median follow-up of 18 months. Overall survival, disease-free survival (DFS), and disease recurrence (DR) at 2 years was 60%, 49%, and 40%, respectively. Immunosuppressed patients had significantly lower 2-year DFS (28% vs. 55%; p=0.003) and higher DR (61% vs. 34%; p=0.04) compared to immunocompetent patients. Analysis of immunocompetent patients demonstrated extracapsular extension (ECE) as the only factor associated with DR (p<0.0001).

CONCLUSION

Patients with nodal metastases from cSCC-HN have suboptimal outcomes. ECE and immunosuppression were significantly associated with DR.

Definitive Chemoradiation in Locally Advanced Squamous Cell Carcinoma of the Hypopharynx: Long-term Outcomes and Toxicity

BACKGROUND/AIM

Definitive chemoradiation (CRT) is a common approach for locally advanced hypopharyngeal squamous cell carcinoma (SCC) with the goal of organ preservation. Reports on long-term oncologic and functional outcomes have been limited. This study reports on outcomes utilizing this approach at a single institution over 30 years.

MATERIALS AND METHODS

Medical records for patients with stage III-IVB SCC of the hypopharynx were retrospectively reviewed. Patient and disease-related factors were identified and analyzed for impact on overall survival (OS), cancer-specific survival (CSS), disease-free survival, distant failure, and locoregional failure.

RESULTS

A total of 54 patients were identified who were treated with definitive CRT to a mean dose of 72 Gy. With a median follow-up period of 49.8 months, 5- and 10-year OS was 62% and 43% respectively. Five and 10-year CSS were 74% and 72% respectively. Ten-year local control was 78%. Of the 37 patients with no treatment failure, 29% experienced a grade 3 or higher late toxicity, with the majority resolving during continued long-term follow-up.

CONCLUSION

This study demonstrates good outcomes with long-term follow-up with acceptable rates of late toxicities. The findings here represent the longest published median follow-up in this population and validate the strategy of organ preservation.

Dosimetric differences between local failure and local controlled non-small cell lung cancer patients treated with stereotactic body radiotherapy: A matched-pair study

INTRODUCTION

Concerns were raised about the accuracy of pencil beam (PB) calculation and potential underdosing of medically inoperable non-small cell lung cancer (NSCLC) treated with stereotactic body radiation therapy (SBRT). From our institutional series, we designed a matched-pair study where each local failure and controlled patient was matched based upon several clinical factors, to investigate the dose difference between the matched-pair.

METHODS

Eighteen pairs of NSCLC patients, treated with 50 Gy in five fractions, were selected. These patients were matched based on treatment intent, tumour size, histology and clinical follow-up. All PB calculated clinical plans were retrospectively recalculated with a MC algorithm. The D₉₉ and D_Mean of the gross tumour volume (GTV) and D₉₅ and D_Mean of the planning tumour volume (PTV) from PB and Monte Carlo (MC) calculation were compared between local failures and controls using the Mann-Whitney test.

RESULTS

The mean PB calculated D95 of PTV was 50.4 Gy for both failures and controls (P = 0.85), indicating no planning differences between the groups. From MC calculations, the mean (±SD) of GTV D₉₉ , GTV D_Mean , PTV D₉₅ , PTV D_Mean were 47.6 ± 2.6/46.3 ± 2.4, 50.4 ± 2.1/49.8 ± 1.6, 44.4 ± 2.7/43.6 ± 3.1, 48.7 ± 2.4/48.2 ± 2.4 Gy for failure/controlled groups, respectively, and there was no significant difference between two groups (all P > 0.1). The dose differences between MC and PB calculations were in agreement with other literatures and there was no significant difference between two groups.

CONCLUSIONS

While PB algorithms may overestimate tumour doses relative to MC algorithms, our matched-pair study did not find dose differences between local failure and local controlled cases.

A matched comparison of human papillomavirus-induced squamous cancer of unknown primary with early oropharynx cancer

OBJECTIVES/HYPOTHESIS

Patients with human papillomavirus (HPV)-induced cancer of unknown primary (CUP) are generally excluded from clinical trials, despite surgical series reporting detection rates of occult oropharynx primaries of >80%. We performed a matched-pair analysis to compare outcomes between T0N1-3M0 HPV+ CUP and T1-2N1-3M0 HPV+ oropharynx known primary (OPX).

STUDY DESIGN

Retrospective cohort study at a single institution.

METHODS

Patients with early T stage, node positive HPV+ OPX or CUP treated with curative intent between 1998 and 2016 were identified. For a subgroup of CUP patients with an unknown HPV status, we imputed HPV status and included patients with a >80% probability of being HPV+. Cohorts were matched based on patient demographics using a nearest neighbor propensity technique. After matching, patients were grouped according to either a favorable or unfavorable risk stratification designations per current NRG Oncology clinical trial enrollment criteria. Disease-free survival (DFS) and overall survival (OS) were calculated using Kaplan-Meier analysis.

RESULTS

Of 298 patients with T1-2N1-3 OPX, 48 were matched to 48 HPV+ CUP patients (32 with confirmed and 16 imputed HPV status). Median follow-up for CUP (34.1 months) and OPX (27.8 months) patients were similar (P = .23).There were no significant differences between the CUP and OPX groups for 3-year DFS (89% vs. 85%, P = .44), and 3-year OS (91% vs. 91%, P = .11), respectively.

CONCLUSIONS

Patients with T0N+M0 HPV-induced CUP have similar survival outcomes to matched patients with T1-2N+M0 HPV+ OPX. These patients can reasonably be included in clinical trials investigating the role of treatment deintensification and risk stratified similar to patients with early-stage known primary OPX cancer.

LEVEL OF EVIDENCE

4. Laryngoscope, 128:1379-1385, 2018.

Tumor Control and Toxicity for Common Stereotactic Body Radiation Therapy Dose-Fractionation Regimens in Stage I Non-Small Cell Lung Cancer

PURPOSE

To examine the impact of stereotactic body radiation therapy (SBRT) dose on outcomes in early-stage non-small cell lung cancer in a large single-institution series.

METHODS AND MATERIALS

We reviewed 600 patients treated from 2003 to 2012 for early-stage non-small cell lung cancer. The SBRT dose was at physician discretion on the basis of tumor size and location. Peripheral tumors were treated to 60 Gy in 3 fractions (homogeneous planning), 48-50 Gy in 4-5 fractions, or 30-34 Gy in 1 fraction. Central tumors were treated to 50 Gy in 5 fractions, 60 Gy in 8 fractions, or 50 Gy in 10 fractions. Patient, tumor, and treatment factors were assessed for their impact on patterns of failure, toxicity, and survival.

RESULTS

An SBRT dose of 54-60 Gy in 3 fractions was associated with a statistically significant lower rate of local failure (LF) (4.3% at 2 years) compared with 30-34 Gy in 1 fraction (21%), 48-50 Gy in 4-5 fractions (15.5%), and 50-60 Gy in 8-10 fractions (13.3%). Lower pre-SBRT hemoglobin and higher positron emission tomography standardized uptake value were also associated with LF. Nodal failure, distant failure, and overall survival were similar between fractionation groups. Pulmonary toxicity (crude rate, any grade) was slightly higher for 3 fractions (5.0%) compared with 1 (3.2%) or 4-5 fractions (3.8%). Chest wall toxicity was also higher for 3 (23.7%) compared with 1 (8.6%) or 4-5 (7.7%) fraction regimens.

CONCLUSIONS

Although higher biologically equivalent dose SBRT (150-180 Gy₁₀) may be associated with slightly lower LF, it was also associated with mildly increased toxicity and no difference in other patterns of failure or overall survival.

Determinants of short and long term outcomes in patients undergoing immediate breast reconstruction following neoadjuvant chemotherapy

BACKGROUND

We evaluated oncologic outcomes and complications of skin-sparing mastectomy (SSM) and nipple-sparing mastectomy (NSM) with immediate reconstruction (IR) after neoadjuvant chemotherapy (NAC) in patients with early-stage and locally advanced breast cancer (BC).

METHODS

BC patients from 2000 to 2014 treated with NAC followed by SSM/NSM and IR were reviewed. Patient demographics, tumor characteristics, NAC response, complications, and recurrence were analyzed.

RESULTS

Two hundred sixty-nine patients with 280 BCs were treated with NAC followed by SSM (94%) or NSM (6%) with IR. Median age was 47 (26-72) years with a median follow-up of 45 months. Pathologic complete response (pCR) was noted in 49 (17.5%) cases. Overall 30-day complication rate was 13.2%. Variables associated with complications included BMI (P < 0.0001), tobacco use (P = 0.015), and adjuvant radiation (P = 0.025). Local-regional recurrence was 3.2% and metastatic recurrence was 13.2%. Variables predicting recurrence risk were pre-NAC tumor size (P < 0.001), residual tumor size (P = 0.002), Grade III (P = 0.002), HER-2 negative (P = 0.025), pre-NAC nodal disease (P = 0.05), and lack of pCR (P = 0.045).

CONCLUSION

Following NAC, risk factors for complications in patients undergoing SSM/NSM with IR are high BMI, smoking, and adjuvant XRT. SSM/NSM following NAC is associated with excellent local control. These data support expanding the indications for NSM/SSM to include patients receiving NAC.

A Histologic Basis for the Efficacy of SBRT to the lung

PURPOSE

Stereotactic body radiation therapy (SBRT) is the standard of care for medically inoperable patients with early-stage NSCLC. However, NSCLC is composed of several histological subtypes and the impact of this heterogeneity on SBRT treatments has yet to be established.

METHODS

We analyzed 740 patients with early-stage NSCLC treated definitively with SBRT from 2003 through 2015. We calculated cumulative incidence curves using the competing risk method and identified predictors of local failure using Fine and Gray regression.

RESULTS

Overall, 72 patients had a local failure, with a cumulative incidence of local failure at 3 years of 11.8%. On univariate analysis, squamous histological subtype, younger age, fewer medical comorbidities, higher body mass index, higher positron emission tomography standardized uptake value, central tumors, and lower radiation dose were associated with an increased risk for local failure. On multivariable analysis, squamous histological subtype (hazard ratio = 2.4 p = 0.008) was the strongest predictor of local failure. Patients with squamous cancers fail SBRT at a significantly higher rate than do those with adenocarcinomas or NSCLC not otherwise specified, with 3-year cumulative rates of local failure of 18.9% (95% confidence interval [CI]: 12.7-25.1), 8.7% (95% CI: 4.6-12.8), and 4.1% (95% CI: 0-9.6), respectively.

CONCLUSION

Our results demonstrate an increased rate of local failure in patients with squamous cell carcinoma. Standard approaches for radiotherapy that demonstrate efficacy for a population may not achieve optimal results for individual patients. Establishing the differential dose effect of SBRT across histological groups is likely to improve efficacy and inform ongoing and future studies that aim to expand indications for SBRT.

Carotid blowout in a patient with nasopharyngeal carcinoma treated with SBRT re-irradiation for local recurrence using twice weekly treatment

We present the case of a patient undergoing reirradiation for a T4 nasopharyngeal tumor 1 year after his initial radiation, treated with SBRT to a moderate dose with twice weekly fractionation. Despite the measures of caution employed, the patient had a fatal carotid blowout at 7 months following SBRT. This suggests that spacing apart fractions of SBRT alone may not be sufficient to obviate the risk of carotid blowout syndrome and other risk factors and interventions should be considered.

Synchronous non small cell lung cancer nodules treated with stereotactic body radiation therapy (SBRT)

BACKGROUND AND PURPOSE

We compare our institutional outcomes of synchronous primary (SP) lung lesion patients with non-SP patients.Materials and Methods: From an IRB approved prospective registry of 445 NSCLC patients treated with SBRT (8/2005 8/2012), 26 (5.8%) had SPs by biopsy or PET/CT. SBRT was delivered on a Novalis/BrainLAB platform with daily Exactrac set-up.

RESULTS

There were no significant differences comparing SP vs non-SP groups for age, Charlson score, smoking pack years, and PET SUV (p=ns). 18 (69%) SP patients had at least one lesion biopsied. Ipsilateral and bilateral SPs were seen in 10 (38.4%) and 16 (61.6%) respectively. 77% received 50 Gy / 5 fx. SP vs non-SP median follow up was 12 (range 1.5-49.8) vs 15.2 months. Median survival for SP vs non-SP groups was 20.7 vs 28.4 months (p=0.3). In SP vs non-SP groups, local failure was 4% vs 7.6% (p=ns) and nodal/distant failure was 23% vs 24.6% (p=ns). Patients with ipsilateral and bilateral SPs had a 50% vs 14% distant failure respectively (p=0.037).

CONCLUSIONS

After SBRT, there were no differences in survival and patterns of failure for SP vs non-SP patients. Ipsilateral SPs had significantly worse distant failure compared to bilateral SPs.