Long-Term Second Malignancies in Prostate Cancer Patients Treated With Low-Dose-Rate Brachytherapy and Radical Prostatectomy.

PURPOSE: Second malignancy is a rare but potentially lethal event after prostate brachytherapy, but data remain scarce on its long-term risk. The objective of this study is to estimate the number of pelvic second malignancies following brachytherapy compared to radical prostatectomy (RP). MATERIALS AND METHODS: We retrospectively reviewed patients treated with low-dose 125I brachytherapy and RP in British Columbia from 1999 to 2010. Kaplan-Meier estimates for pelvic (bladder and rectum), invasive pelvic, any second malignancy, and death from any second malignancy were assessed. Cox multivariable analyses were performed adjusting for initial treatment type, age, post-RP adjuvant/salvage external beam radiation therapy status, and smoking history. RESULTS: Two thousand three hundred seventy-eight brachytherapy and 9089 RP patients were included. Median age was 66 years (interquartile range [IQR] 61-71) and 63 years (IQR 58-67), respectively. Median follow-up time to event or censured was 14 years (IQR 11.5-17.3). The Kaplan-Meier estimates for pelvic second malignancy at 15 and 20 years were 6.4% and 9.8%, respectively, after brachytherapy, and 3.2% and 4.2% after RP. Time to any second malignancy and time to death from any second malignancy were not significantly different (P > .05). On Cox multivariable analysis, brachytherapy, compared to surgery, was an independent factor for pelvic (hazard ratio [HR] 1.81 [95% CI 1.45-2.26], P < .001) and invasive pelvic second malignancy (HR 2.13 [95% CI 1.61-2.83], P < .001). Increased age and smoking were also associated with higher estimates of events (P < .001). CONCLUSIONS: After adjustment for age, post-RP adjuvant/salvage external beam radiation therapy status, and smoking status, numerically higher long-term HRs of pelvic and invasive pelvic second malignancy in patients treated with brachytherapy compared to RP were noted.

A multi-institutional prediction model to estimate the risk of recurrence and mortality after mastectomy for T1-2N1 breast cancer.

BACKGROUND: Post-mastectomy radiation therapy (PMRT) in women with pathologic stage T1-2N1M0 breast cancer is controversial. METHODS: Data from five North American institutions including women undergoing mastectomy without neoadjuvant therapy with pT1-2N1M0 breast cancer treated from 2006 to 2015 were pooled for analysis. Competing-risks regression was performed to identify factors associated with locoregional recurrence (LRR), distant metastasis (DM), overall recurrence (OR), and breast cancer mortality (BCM). RESULTS: A total of 3532 patients were included for analysis with a median follow-up time among survivors of 6.8 years (interquartile range [IQR], 4.5-9.5 years). The 2154 (61%) patients who received PMRT had significantly more adverse risk factors than those patients not receiving PMRT: younger age, larger tumors, more positive lymph nodes, lymphovascular invasion, extracapsular extension, and positive margins (p < .05 for all). On competing risk regression analysis, receipt of PMRT was significantly associated with a decreased risk of LRR (hazard ratio [HR], 0.21; 95% confidence interval [CI], 0.14-0.31; p < .001) and OR (HR, 0.76; 95% CI, 0.62-0.94; p = .011). Model performance metrics for each end point showed good discrimination and calibration. An online prediction model to estimate predicted risks for each outcome based on individual patient and tumor characteristics was created from the model. CONCLUSIONS: In a large multi-institutional cohort of patients, PMRT for T1-2N1 breast cancer was associated with a significant reduction in locoregional and overall recurrence after accounting for known prognostic factors. An online calculator was developed to aid in personalized decision-making regarding PMRT in this population.

Ninety-day mortality after radiotherapy for head and neck cancer: Population-based comparison between rural and urban patients.

BACKGROUND: This study assesses whether 90-day mortality differs between patients living in rural and urban areas, as lower access to supportive care services in rural areas could result in higher mortality. METHODS: All patients with head and neck cancer (HNC) treated between 1998 and 2014 with radiotherapy in British Columbia were included. Patients were divided into rurality areas according to the Modified Statistics Canada (mSC) definition, which classifies a population <30 000 as rural and ≥30 000 as urban. RESULTS: Five thousand five hundred and fifty-four patients were included in this study, of which 68% lived in urban centers. The 90-day mortality for rural versus urban patients were 3.0% and 3.9% (p = 0.09), respectively. Univariate and multivariate analyses showed no association with 90-day mortality and rurality. CONCLUSION: After controlling for potentially confounding factors, we did not find a significant association between 90-day mortality and rurality in patients who were treated with radiotherapy for HNC in British Columbia.

Association between nutritional risk index and outcomes for head and neck cancer patients receiving concurrent chemo-radiotherapy.

BACKGROUND: Patients receiving chemoradiotherapy for head and neck cancer (HNC) are often malnourished. We assessed the utility of nutritional risk index (NRI) in HNC patients undergoing chemoradiotherapy. METHODS: A population-based retrospective review of HNC patients treated with curative chemoradiation was performed. Demographics, anthropometrics, overall survival (OS), and the composite treatment complication rate (G-tube dependence, radiation incompletion, 90-day mortality, and unplanned hospitalization) were collected. RESULTS: Two hundred ninety-two patients were identified. Average pretreatment and posttreatment NRI were 110 (SD 3) and 99 (SD 12), respectively (P < .01). Pretreatment NRI risk category, age, ECOG status, and tumor subsites were associated with OS on multivariate analysis. Pretreatment NRI risk category was associated with risk of treatment related complications. CONCLUSIONS: There was a significant decrease between pretreatment and posttreatment NRI in HNC patients receiving chemoradiation. Pretreatment NRI risk category may predict OS and composite treatment complications. Investigation of NRI as a prognostic factor is warranted.

The role of external beam radiation therapy in well-differentiated thyroid cancer.

INTRODUCTION: This review article explores the use of external beam radiotherapy (EBRT) in well differentiated thyroid cancer. Areas covered: The published literature on EBRT for advanced pT4 disease and macroscopic unresectable disease to improve locoregional control is reviewed. EBRT techniques, volumes and doses are discussed in detail. The potential acute and late toxicities of EBRT are discussed in the context of the published literature. The use of EBRT for patients with metastatic disease is also described. Expert commentary: There is good retrospective evidence for EBRT in the setting of unresectable gross residual well-differentiated thyroid cancer as this can result in long-term local control. However, the benefit of EBRT in patients with locally advanced disease that is completely resected is less clear. The use of EBRT for these patients requires careful consideration of age, pathologic factors, comorbidities and patient preference, preferably by a multi-disciplinary team.

Long-term Outcomes and Complications in Pediatric Ewing Sarcoma.

OBJECTIVES: The objective of this study was to determine treatment outcomes and long-term complications in pediatric patients with Ewing Sarcoma treated at the British Columbia Cancer Agency (BCCA). METHODS: A retrospective chart review of 101 pediatric patients (<19 y old) with Ewing Sarcoma diagnosed between 1960 and 2005 was performed. The Kaplan-Meier survival analysis and Cox regression multivariate analysis were used to assess prognostic factors for overall survival (OS) and event-free survival (EFS). RESULTS: The median age at diagnosis was 11 years and the median follow-up for nondeceased patients was 13.5 years. The most common primary tumor locations were lower extremity (33%), pelvis (24%), and thorax (18%). Fifty percent of patients received surgery, 79% radiotherapy and 94% chemotherapy. The 5-year OS and EFS for patients with localized disease was 85% and 73% and for metastatic disease was 27% (P<0.0001) and 28% (P<0.0001), respectively. Metastatic disease was an independent predictor of lower OS (hazard ratio [HR], 9.5; 95% confidence interval [CI],4.7-19.4; P<0.0001) and EFS (HR, 4.9; 95% CI, 2.7-8.8; P<0.0001). Extremity tumor location was an independent predictor for improved OS (HR, 0.4; 95% CI, 0.2-0.9; P=0.03). The majority (77%) of long-term survivors (≥5 y) had long-term complications; the most common were musculoskeletal abnormalities (50%) and cardiac toxicity (28%). The actuarial second neoplasm risk was 5% at 10 years. CONCLUSIONS: Ewing sarcoma patients with localized disease had excellent treatment outcomes at the BCCA. However, the majority of patients had chronic complications from treatment. This study validates the need for long-term follow-up of Ewing Sarcoma survivors for management of late effects.

Asian Versus Non-Asian Outcomes in Nasopharyngeal Carcinoma: A North American Population-based Analysis.

OBJECTIVES: The effect of ethnicity on nasopharyngeal cancer (NPC) outcomes is unclear. This retrospective analysis examines survival and the impact of concurrent chemoradiation (chemoRT) among Asian and non-Asian patients. METHODS: Subjects included 380 consecutive patients with NPC treated at a Canadian institution from 2000 to 2009. Five-year Kaplan-Meier progression-free survival (PFS), disease-specific survival (DSS), and overall survival (OS) were compared between Asian (n=279) and non-Asian (n=101) subjects. Multivariable analysis was performed using Cox regression modeling. Two-variable interaction terms with concurrent chemoRT were used to examine whether concurrent chemoRT conferred different effects among subgroups. RESULTS: Asian subjects presented with earlier stage (P=0.005), were younger, had better performance status, and were less likely smokers (all P<0.001). Survival among Asian versus non-Asian subjects with stage I/II NPC were: PFS 68% versus 59% (P=0.04), DSS 87% versus 77% (P=0.08), and OS 84% versus 74% (P=0.003). Corresponding rates with stage III/IVA/IVB disease were PFS 49% versus 42% (P=0.12), DSS 72% versus 46% (P=0.001), and OS 70% versus 44% (P<0.001). On multivariable analysis, Asian ethnicity, age below 65 years, ECOG performance status 0-1, early stage, staging MRI use, and concurrent chemoRT were associated with improved DSS and OS (P<0.05). On testing interactions with concurrent chemoRT, Asian versus non-Asian ethnicity was significant (hazard ratio 3.9), suggesting that concurrent chemoRT conferred more benefit among non-Asian compared with Asian subjects. CONCLUSIONS: In this population-based study, Asian ethnicity was associated with improved DSS and OS. Concurrent chemoRT conferred more benefit among non-Asian compared with Asian subjects.

Treatment and outcomes in patients with primary cutaneous B-cell lymphoma: the BC Cancer Agency experience.

PURPOSE: To review the treatment and outcomes of patients with primary cutaneous B-cell lymphoma (CBCL). METHODS AND MATERIALS: Clinical characteristics, treatment, and outcomes were analyzed for all patients referred to our institution from 1981 through 2011 with primary CBCL without extracutaneous or distant nodal spread at diagnosis (n=136). Hematopathologists classified 99% of cases using the World Health Organization-European Organization for Research and Treatment of Cancer (WHO-EORTC) guidelines. RESULTS: Median age at diagnosis was 62 years. Classification was 18% diffuse large B-cell leg-type (DLBCL-leg), 32% follicle center (FCCL), 45% marginal zone (MZL), and 6% nonclassifiable (OTHER). Of the 111 subjects with indolent lymphoma (FCCL, MZL, OTHER), 79% received radiation alone (RT), 11% surgery alone, 3% chemotherapy alone, 4% chemotherapy followed by RT, and 3% observation. Following treatment, 29% of subjects relapsed. In-field recurrence occurred in 2% treated with RT and in 33% treated with surgery alone. Of the 25 subjects with DLBCL-leg, 52% received chemotherapy followed by RT, 24% chemotherapy, 20% RT, and 4% surgery alone. Seventy-nine percent received CHOP-type chemotherapy (cyclophosphamide, doxorubicin or epirubicin, vincristine, prednisone), 47% with rituximab added. Overall and disease-specific survival and time to progression at 5 years were 81%, 92%, and 69% for indolent and 26%, 61%, and 54% for DLBCL-leg, respectively. On Cox regression analysis of indolent subjects, RT was associated with better time to progression (P=.05). RT dose, chemo, age>60 y, and >1 lesion were not significantly associated with time to progression. For DLBCL-leg, disease-specific survival at 5 years was 100% for those receiving rituximab versus 67% for no rituximab (P=.13). CONCLUSIONS: This review demonstrates better outcomes for indolent histology compared with DLBCL-leg, validating the prognostic utility of the WHO-EORTC classification. In the indolent group, RT was associated with 98% local control. DLBCL-leg is a more aggressive disease; the excellent results in the rituximab group suggest it has an important role in management.