Faculty Bibliography

PURPOSE: The National Cancer Data Base was analyzed to evaluate the patterns of care and impact of brachytherapy (BT) boost on overall survival (OS) for patients with squamous cell carcinoma of the base of tongue. METHODS AND MATERIALS: Patients with nonmetastatic squamous cell carcinoma of the base of tongue between 2004 and 2012 who received concurrent external beam radiation therapy (EBRT) and chemotherapy with or without BT boost in the definitive setting were queried. Overall survival was assessed by the Kaplan-Meier method. Cox regression analysis was used to identify covariates that affected OS. RESULTS: There were 15,934 patients included in this study; 137 (0.9%) received EBRT + BT and the remaining received EBRT only. Median followup was 41.2 months. The utilization of BT boost declined from 2.1% in 2004 to 0.2% in 2012 (p < 0.0001), whereas intensity-modulated radiation therapy use increased from 22.8% in 2004 to 69.2% in 2012 (p < 0.0001). The three- and 5-year OS was 83.2% and 78.3% for patients receiving EBRT + BT compared with 77.4% and 69.0% for those receiving EBRT only (p = 0.03). The difference in survival was significantly better among patients with T3-4 tumors with EBRT + BT boost (p = 0.009) however, there was no survival benefit among patients with T1-2 tumors (p = 0.72). The analysis was repeated with patients who received intensity-modulated radiation therapy vs. EBRT with BT boost and the survival difference was sustained only for those with T3-4 tumors (p = 0.02). CONCLUSIONS: Brachytherapy boost has decreased in its utilization even though it was associated with favorable survival outcomes particularly among patients with higher T-stage tumors.

BACKGROUND AND PURPOSE: We evaluated the effect of post-mastectomy radiation (PMRT) in 1-3 positive lymph nodes (LN) in patients who received uniform modern systemic therapy. MATERIALS AND METHODS: Cohort study using individual data collected for 1,649 node-positive women who received doxorubicin/cyclophosphamide with sequential docetaxel in 2000-2003 on the control arm of BCIRG-005. All women underwent mastectomy or lumpectomy and axillary LN dissection. PMRT was given at investigator's discretion. RESULTS: A total of 523 women with 1-3 positive LN underwent mastectomy and 39% (206/523) received PMRT. With a median follow-up of 10years, PMRT improved loco-regional control (LRC) from 91% to 98% (p=0.001) but had no effect on overall survival (OS) (84% vs. 86%, p=0.9). On multivariate analysis, PMRT improved local control (LC) (hazard ratio, 0.14; 95% CI, 0.03-0.62; p=0.01) and LRC (hazard ratio, 0.15; 95% CI, 0.04-0.50; p=0.002). PMRT did not significantly impact OS on multivariate analysis (hazard ratio, 0.91; 95% CI, 0.55-1.51; p=0.7). Results remained consistent with the use of propensity score analysis. CONCLUSIONS: In this cohort of patients with N1 disease treated with modern systemic therapy, PMRT improves LRC but has no effect on OS. The rates of OS were excellent, irrespective of adjuvant radiation.

BACKGROUND:To investigate the dose-volume factors in mastication muscles that are implicated as possible causes of trismus in patients following treatment with intensity-modulated radiotherapy (IMRT) and concurrent chemotherapy for head and neck cancers. MATERIAL AND METHODS/METHODS:All evaluable patients treated at our institution between January 2004 and April 2009 with chemotherapy and IMRT for squamous cell cancers of the oropharynx, nasopharynx, hypopharynx or larynx were included in this analysis (N = 421). Trismus was assessed using CTCAE 4.0. Bi-lateral masseter, temporalis, lateral pterygoid and medial pterygoid muscles were delineated on axial computed tomography (CT) treatment planning images, and dose-volume parameters were extracted to investigate univariate and multimetric correlations. RESULTS:Forty-six patients (10.9%) were observed to have chronic trismus of grade 1 or greater. From analysis of baseline patient characteristics, toxicity correlated with primary site and patient age. From dose-volume analysis, the steepest dose thresholds and highest correlations were seen for mean dose to ipsilateral masseter (Spearman's rank correlation coefficient Rs = 0.25) and medial pterygoid (Rs = 0.23) muscles. Lyman-Kutcher-Burman modeling showed highest correlations for the same muscles. The best correlation for multimetric logistic regression modeling was with V68Gy to the ipsilateral medial pterygoid (Rs = 0.29). CONCLUSION/CONCLUSIONS:Chemoradiation-induced trismus remains a problem particularly for patients with oropharyngeal carcinoma. Strong dose-volume correlations support the hypothesis that limiting dose to the ipsilateral masseter muscle and, in particular, the medial pterygoid muscle may reduce the likelihood of trismus.

BACKGROUND:Previous groups have shown contralateral submandibular gland sparing to improve xerostomia with safe outcomes, but primarily in early-stage disease. In this study, we present a large cohort of patients with locally advanced head and neck cancer that underwent contralateral submandibular gland-sparing radiotherapy, to demonstrate feasibility and safety specifically in patients with locally advanced disease. METHODS:We retrospectively analyzed patients who were treated prospectively with contralateral submandibular gland sparing. Only patients who underwent bilateral neck radiotherapy with contralateral submandibular gland doses <39 Gy were included. RESULTS:We identified 71 patients. Approximately 80% of patients had ≥N2b disease. The contralateral submandibular gland mean dose was 33 Gy and, at a median follow-up of 27.3 months, no patients experienced treatment failure in the contralateral level IB lymph nodes. CONCLUSION/CONCLUSIONS:Xerostomia remains a significant morbidity despite parotid sparing and can be minimized further by contralateral submandibular gland sparing. These data provide important preliminary evidence that contralateral submandibular gland sparing is feasible and may be safe even in locally advanced cancers.

OBJECTIVES/OBJECTIVE:To assess whether sparing neck-level IB in target delineation of node-positive (N+) oropharyngeal carcinoma (OPC) can improve xerostomia outcomes without compromising locoregional control (LRC). METHODS:A total of 125 N+ OPC patients with a median age of 57 years underwent chemoradiation between May 2010 and December 2011. A total of 74% of patients had T1-T2 disease, 26% T3-T4, 16% N1, 8% N2A, 48% N2B, 28% N2C; 53% base of tongue, 41% tonsil, and 6% other. Patients were divided into those who had target delineation sparing of bilateral level IB (the spared cohort) versus no sparing (the treated cohort). Sparing of contralateral high-level II nodes was also performed more consistently in the spared cohort. A prospective xerostomia questionnaire (patient reported) was given at each patient follow-up visit to this cohort of patients to assess late xerostomia. Clinical assessment (observer rated) at each patient follow-up visit was also recorded. RESULTS:The 2-year LRC for the spared and treated cohorts was 97.5% and 93.8%, respectively (median follow-up, 23.2 mo). No locoregional failures occurred outside of treatment fields. The spared cohort experienced significant benefits in patient-reported xerostomia summary scores (P=0.021) and observer-rated xerostomia scores (P=0.006). In addition, there were significant reductions in mean doses to the ipsilateral submandibular gland (63.9 vs. 70.5 Gy; P<0.001), contralateral submandibular gland (45.0 vs. 56.2 Gy; P<0.001), oral cavity (35.9 vs. 45.2 Gy; P<0.001), and contralateral parotid gland (20.0 vs. 24.4 Gy; P<0.001). CONCLUSIONS:Target delineation sparing of bilateral level IB nodes in N+ OPC reduced mean doses to salivary organs without compromising LRC. Patients with reduced target volumes had better patient-reported xerostomia outcomes.

INTRODUCTION: We expanded upon our previous experience using involved-field fractionated radiotherapy (IFRT) as an alternative to whole brain radiotherapy or stereotactic radiosurgery for patients with surgically resected brain metastases (BM). MATERIALS AND METHODS: All patients with single BM who underwent surgical resection followed by IFRT at our institution from 2006 to 2013 were evaluated. Local recurrence (LR)-free survival, distant failure (DF)-free survival, and overall survival (OS) were determined. Analyses were performed associating clinical variables with LR and DF. Salvage approaches and toxicity of treatment for each patient were also assessed. RESULTS: Median follow-up was 19.1 months. Fifty-six patients were treated with a median dose of 40.05 Gy/15 fractions with IFRT to the resection cavity. LR-free survival was 91.4%, DF-free survival was 68.4%, and OS was 77.7% at 12 months. No variables were associated with increased LR; however, melanoma histopathology and infratentorial location were associated with DF on multivariate analysis. LRs were salvaged in 5/8 patients, and DFs were salvaged in 24/29 patients. Two patients developed radionecrosis. CONCLUSION: Adjuvant IFRT is feasible and safe for well-selected patients with surgically resected single BM. Acceptable rates of local control and salvage of distal intracranial recurrences continue to be achieved with continued follow-up.

BACKGROUND:The results of RTOG-MRC randomized trial of photon (n=15) versus neutron (n=17) therapy in the 1980's reported an improved local control (LC) with neutron radiotherapy for unresectable salivary gland tumors. Due to increased severe toxicity with neutron radiotherapy and the paucity of neutron-therapy centers, we analyzed our institution's results of photon radiotherapy for unresectable salivary gland tumors. PATIENTS AND METHODS/METHODS:From 1990 to 2009, 27 patients with unresectable salivary gland cancer underwent definitive photon radiotherapy at our institution. Nodal involvement on presentation was found in 9 patients. Median dose of radiotherapy was 70 Gy. Chemotherapy was given to 18 patients, most being platinum-based regimens. Local control (LC), locoregional control (LRC), distant metastasis-free survival (DMFS), overall survival (OS), and toxicity outcomes were assessed. RESULTS:With a median follow-up of 52.4 months, the 2/5-year actuarial LC was 69% (95%CI ± 21.0%)/55% (± 24.2%), LRC was 65% (± 21.4%)/47% (± 21.6%), and DMFS was 71% (± 21.8%)/51% (± 22.8%), respectively using competing risk analysis. The median OS was 25.7 months, and the 2/5-year OS rates were 50% (± 19.0%)/29% (± 16.6%), respectively. Higher histologic grade was significant for an increased rate of DM (intermediate grade vs. low grade, p=0.04, HR 7.93; high grade vs. low grade, p=0.01, HR 13.50). Thirteen (48%) patient's experienced acute grade 3 toxicity. Late grade 3 toxicity occurred in three (11%) patients. CONCLUSIONS:Our data compares favorably to neutron radiotherapy with fewer late complications. Photon radiotherapy is an acceptable alternative to neutron radiotherapy in patients who present with unresectable salivary gland tumors.

PURPOSE/OBJECTIVE:We sought to identify risk factors for distant metastasis (DM) in patients with oropharyngeal cancer (OPC) and perform a recursive partition analysis (RPA) to identify patients both at low and high risk for DM. METHODS:Our center treated 647 consecutive OPC patients with IMRT between 9/98 and 1/12. The following clinical features were used as prognostic factors: T Stage, N Stage, smoking history, tumor grade, tumor sub-site, the presence of a low lying (level IV or VB) lymph node (LLLN). A Cox model of the risk of DM was used to identify independent prognostic factors. RPA was used to identify patients at low, intermediate, and high risk for DM. RESULTS:The median follow-up time in living patients was 42.2months (range: 2-166). The primary OPC site was the tonsil in 296 patients, base of tongue in 315 patients, and soft palate or pharyngeal wall in 36 patients. For the entire cohort, the Kaplan-Meier estimate for 3year freedom from distant metastasis was 88.4%. A Cox model identified T Stage (p<0.001), N Stage (p=0.02), and LLLN (p=0.002) as independent predictors of DM. RPA identified patients at low, intermediate, and high risk of DM, with a 3-year freedom-from DM of 98%, 91.1%, and 65.4% respectively. CONCLUSION/CONCLUSIONS:The presence of a low lying lymph node is significantly associated with an increased risk of DM in OPC. RPA identified patients both at very low and very high risk for DM with information routinely obtained in clinic.