Temporary organ displacement coupled with image-guided, intensity-modulated radiotherapy for paraspinal tumors.

BACKGROUND: To investigate the feasibility and dosimetric improvements of a novel technique to temporarily displace critical structures in the pelvis and abdomen from tumor during high-dose radiotherapy. METHODS: Between 2010 and 2012, 11 patients received high-dose image-guided intensity-modulated radiotherapy with temporary organ displacement (TOD) at our institution. In all cases, imaging revealed tumor abutting critical structures. An all-purpose drainage catheter was introduced between the gross tumor volume (GTV) and critical organs at risk (OAR) and infused with normal saline (NS) containing 5-10% iohexol. Radiation planning was performed with the displaced OARs and positional reproducibility was confirmed with cone-beam CT (CBCT). Patients were treated within 36 hours of catheter placement. Radiation plans were re-optimized using pre-TOD OARs to the same prescription and dosimetrically compared with post-TOD plans. A two-tailed permutation test was performed on each dosimetric measure. RESULTS: The bowel/rectum was displaced in six patients and kidney in four patients. One patient was excluded due to poor visualization of the OAR; thus 10 patients were analyzed. A mean of 229 ml (range, 80-1000) of NS 5-10% iohexol infusion resulted in OAR mean displacement of 17.5 mm (range, 7-32). The median dose prescribed was 2400 cGy in one fraction (range, 2100-3000 in 3 fractions). The mean GTV Dmin and PTV Dmin pre- and post-bowel TOD IG-IMRT dosimetry significantly increased from 1473 cGy to 2086 cGy (p=0.015) and 714 cGy to 1214 cGy (p=0.021), respectively. TOD increased mean PTV D95 by 27.14% of prescription (p=0.014) while the PTV D05 decreased by 9.2% (p=0.011). TOD of the bowel resulted in a 39% decrease in mean bowel Dmax (p=0.008) confirmed by CBCT. TOD of the kidney significantly decreased mean kidney dose and Dmax by 25% (0.022). CONCLUSIONS: TOD was well tolerated, reproducible, and facilitated dose escalation to previously radioresistant tumors abutting critical structures while minimizing dose to OARs.

Incidence of secondary cancer development after high-dose intensity-modulated radiotherapy and image-guided brachytherapy for the treatment of localized prostate cancer.

PURPOSE: To report the incidence and excess risk of second malignancy (SM) development compared with the general population after external beam radiotherapy (EBRT) and brachytherapy to treat prostate cancer. METHODS AND MATERIALS: Between 1998 and 2001, 1,310 patients with localized prostate cancer were treated with EBRT (n = 897) or brachytherapy (n = 413). We compared the incidence of SMs in our patients with that of the general population extracted from the National Cancer Institute's Surveillance, Epidemiology, and End Results data set combined with the 2000 census data. RESULTS: The 10-year likelihood of SM development was 25% after EBRT and 15% after brachytherapy (p = .02). The corresponding 10-year likelihood for in-field SM development in these groups was 4.9% and 1.6% (p = .24). Multivariate analysis showed that EBRT vs. brachytherapy and older age were the only significant predictors for the development of all SMs (p = .037 and p = .030), with a trend for older patients to develop a SM. The increased incidence of SM for EBRT patients was explained by the greater incidence of skin cancer outside the radiation field compared with that after brachytherapy (10.6% and 3.3%, respectively, p = .004). For the EBRT group, the 5- and 10-year mortality rate was 1.96% and 5.1% from out-of field cancer, respectively; for in-field SM, the corresponding mortality rates were 0.1% and 0.7%. Among the brachytherapy group, the 5- and 10-year mortality rate related to out-of field SM was 0.8% and 2.7%, respectively. Our observed SM rates after prostate RT were not significantly different from the cancer incidence rates in the general population. CONCLUSIONS: Using modern sophisticated treatment techniques, we report low rates of in-field bladder and rectal SM risks after prostate cancer RT. Furthermore, the likelihood of mortality secondary to a SM was unusual. The greater rate of SM observed with EBRT vs. brachytherapy was related to a small, but significantly increased, number of skin cancers in the EBRT patients compared with that of the general population.

Prognostic value of triple-negative phenotype at the time of locally recurrent, conservatively treated breast cancer.

PURPOSE: To evaluate the prognostic value of triple-negative (TN) ER, PR, Her2/neu basal-like carcinoma of the breast, at the time of ipsilateral breast tumor recurrence (IBTR) after conservative surgery and radiation treatment (RT). METHODS AND MATERIALS: A tissue microarray was constructed of 47 IBTR specimens of patients who experienced an IBTR after conservative surgery and RT that were processed and stained for ER, PR, and HER2/neu. RESULTS: At a median post-recurrence follow-up of 7.5 years, the 5-year overall survival (OS) and disease metastasis-free survival (DMFS) after IBTR were 91.4% and 83.0%, respectively. Median time to tumor recurrence (TTR) and IBTR was shorter in the TN phenotype (3.88 vs. 5.00 years; p = 0.09). The TN tumors were not associated with size of local recurrence or recurrence elsewhere in the breast. Despite administration of standard chemotherapy at the time of IBTR, the 5-year DMFS and 5-year OS for the TN cohort were 48.6% and 72.7%, respectively. The 5-year DMFS was 48.6% for TN tumors and 90.8% for non-TN tumors (p < 0.01). By univariate analysis, significant factors associated with poor 5-year DMFS and OS after IBTR included: TN phenotype (p < 0.01), TTR 3 years or less (p < 0.01), local recurrence at or near the original tumor site (p = 0.08). In multivariate analysis, TN was a significant independent predictor of poorer 5-year DMFS (relative risk, 5.91; 95% confidence interval, 1.83-19.01; p < 0.01) after IBTR. CONCLUSIONS: Although patients experiencing an IBTR have a relatively favorable prognosis, those with IBTR events of the TN phenotype had a rather poor prognosis despite receiving standard chemotherapy. Strategies with novel systemic therapies to improve outcomes in patients experiencing IBTR of the TN phenotype are warranted.

Radiotherapy for thymoma and thymic carcinoma.

The role of radiotherapy for patients who have thymic neoplasms remains unclear. The low incidence of thymic malignancies, excellent outcome with complete resection, and limited body of evidence obfuscate the role of radiation therapy within the current multidisciplinary management of disease. Nonetheless, existing literature reports and novel radiotherapy techniques show increasing potential for integration of radiotherapy into the standard therapeutic milieu for carefully selected patient subpopulations.

Analysis of primary CD30+ cutaneous lymphoproliferative disease and survival from the Surveillance, Epidemiology, and End Results database.

PURPOSE: Primary CD30+ cutaneous lymphoproliferative disease (PCLPD) is a spectrum of indolent cutaneous T-cell lymphomas. The primary intention of the analysis of the National Cancer Institute Surveillance, Epidemiology, and End Results (SEER) database was to report epidemiologic information and overall survival of patients with PCLPD. METHODS: We investigated the SEER database from 1973 to 2004 and performed univariable and multivariable survival analysis. RESULTS: A total of 268 cases of PCLPD were recorded from 1973 to 2004. Median age at diagnosis was 61 years (range, 5 to 98 years). Among cases, 58% were male, and 42% female. Race distribution was 87% white, 7% black, and 4% Asian/Pacific Islander. A total of 157 patients had primary, localized PCLPD. For the total population (N = 268), overall survival at 3 years was 81% (95% CI, 74% to 87%). Population-matched relative survival at 3 years was 87% (SE, 3.6%). Disease-specific survival at 5 years was 92% (95% CI, 86% to 95%). Head and neck skin site predicted for inferior overall survival in patients with primary, localized PCLPD on univariable analysis (hazard ratio [HR] = 4.4; P = .008; 95% CI, 1.5 to 13.2), and was suggestive of decreased overall survival on multivariate analysis (HR = 3.0; P = .06; 95% CI, 0.95 to 9.7). CONCLUSION: Localized PCLPDs are rare diseases with an excellent overall survival and occur more frequently in whites and in men. Head and neck skin primary site may be associated with poorer survival. CONCLUSIONS regarding subsets demonstrating association with survival should be taken with caution, given the small number of deaths analyzed.