Organ sparing treatment for penile cancer using a 3D-printed high-dose-rate brachytherapy applicator.

PURPOSE: We present a case study of the treatment of localized squamous cell carcinoma on the glans penis with a custom-fabricated high-dose-rate (HDR) brachytherapy applicator. METHODS AND MATERIALS: A cylindrically shaped applicator was fabricated with eight embedded channels suitable for standard plastic brachytherapy catheters. An additional custom silicone bolus/sleeve was designed to be used with the 3D-printed applicator to provide an additional offset from the source to skin to reduce the surface dose and for patient comfort. RESULTS: The patient (recurrent cT1a penile cancer) underwent CT simulation, and the brachytherapy plan was created with a nominal prescription dose of 40 Gy in 10 fractions given bidaily to the surface, and 35 Gy at 5 mm depth. Dose coverage to the clinical target volume was 94% (D90). Most fractions were treated with only 5-10 min of setup time. Follow up visits up to 1 year showed no evidence of disease with no significant changes in urinary and sexual function and limited cosmetic detriment to the patient. CONCLUSIONS: Patient-specific organ-sparing HDR plesiotherapy using 3D printing technology can provide reliable and reproducible patient setup and may be effective in achieving disease control for superficial penile cancer, although preserving patient quality of life.

Accuracy and Clinical Utility of a Tumor Grade- and Stage-based Predictive Model in Localized Upper Tract Urothelial Carcinoma.

BACKGROUND: Among various clinicopathologic factors used to identify low-risk upper tract urothelial carcinoma (UTUC), tumor grade and stage are of utmost importance. The clinical value added by inclusion of other risk factors remains unproven. OBJECTIVE: To assess the performance of a tumor grade- and stage-based (GS) model to identify patients with UTUC for whom kidney-sparing surgery (KSS) could be attempted. DESIGN, SETTING, AND PARTICIPANTS: In this international study, we reviewed the medical records of 1240 patients with UTUC who underwent radical nephroureterectomy. Complete data needed for risk stratification according to the European Association of Urology (EAU) and National Comprehensive Cancer Network (NCCN) guidelines were available for 560 patients. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Univariable and multivariable logistic regression analyses were performed to determine if risk factors were associated with the presence of localized UTUC. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of the GS, EAU, and NCCN models in predicting pathologic stage were calculated. RESULTS AND LIMITATIONS: Overall, 198 patients (35%) had clinically low-grade, noninvasive tumors, and 283 (51%) had ≤pT1disease. On multivariable analyses, none of the EAU and NCCN risk factors were associated with the presence of non-muscle-invasive UTUC among patients with low-grade and low-stage UTUC. The GS model exhibited the highest accuracy, sensitivity, and negative predictive value among all three models. According to the GS, EAU, and NCCN models, the proportion of patients eligible for KSS was 35%, 6%, and 4%, respectively. Decision curve analysis revealed that the net benefit of the three models was similar within the clinically reasonable range of probability thresholds. CONCLUSIONS: The GS model showed favorable predictive accuracy and identified a greater number of KSS-eligible patients than the EAU and NCCN models. A decision-making algorithm that weighs the benefits of avoiding unnecessary kidney loss against the risk of undertreatment in case of advanced carcinoma is necessary for individualized treatment for UTUC patients. PATIENT SUMMARY: We assessed the ability of three models to predict low-grade, low-stage disease in patients with cancer of the upper urinary tract. No risk factors other than grade assessed on biopsy and stage assessed from scans were associated with better prediction of localized cancer. A model based on grade and stage may help to identify patients who could benefit from kidney-sparing treatment of their cancer.

The Rho GTPase signalling pathway in urothelial carcinoma.

Urothelial carcinoma remains a clinical challenge: non-muscle-invasive disease has a high rate of recurrence and risk of progression, and outcomes for patients with advanced disease are poor, owing to a lack of effective systemic therapies. The Rho GTPase family of enzymes was first identified >30 years ago and contains >20 members, which are divided into eight subfamilies: Cdc42, Rac, Rho, RhoUV, RhoBTB, RhoDF, RhoH, and Rnd. Rho GTPases are molecular on-off switches, which are increasingly being understood to have a critical role in a number of cellular processes, including cell migration, cell polarity, cell adhesion, cell cycle progression, and regulation of the cytoskeleton. This switch is an evolutionarily conserved system in which GTPases alternate between GDP-bound (inactive) and GTP-bound (active) forms. The activities of these Rho GTPases are many, context-dependent, and regulated by a number of proteins that are being progressively elucidated. Aberrations of the Rho GTPase signalling pathways have been implicated in various malignancies, including urothelial carcinoma, and understanding of the role of Rho GTPases in these diseases is increasing. This signalling pathway has the potential for therapeutic targeting in urothelial carcinoma. Research in this area is nascent, and much work is necessary before current laboratory-based research can be translated into the clinic.

Neoadjuvant (presurgical) therapy for renal cell carcinoma: a new treatment paradigm for locally advanced and metastatic disease.

BACKGROUND: Although upfront cytoreductive nephrectomy followed by systemic therapy remains the standard of care for metastatic renal cell carcinoma, the addition of novel targeted therapy has prompted a reevaluation of this treatment paradigm. The authors reviewed their experience with neoadjuvant systemic therapy administered before cytoreductive surgery for metastatic, locally recurrent, or regionally advanced renal cell carcinoma. METHODS: The authors compared patients treated with presurgical targeted therapy (with sunitinib, sorafenib, or bevacizumab) with a contemporary group that underwent up-front cytoreductive surgery. RESULTS: The authors found no difference in any perioperative surgical parameters indicative of morbidity or mortality between the 2 groups. Laboratory models of renal cell carcinoma treated with systemic targeted therapy demonstrate specific protein expression profiles that correlate with response to therapy and the development of therapy resistance. CONCLUSIONS: Neoadjuvant (presurgical) targeted therapy before cytoreductive surgery appears safe in the setting of metastatic renal cell carcinoma. It identifies patients who respond to systemic therapy before surgery, thus avoiding highly morbid surgery in patients destined for a poor outcome. Further studies are needed to identify the molecular endpoints associated with treatment response and the development of the resistant phenotype, which will in turn identify novel transduction pathways worthy of therapeutic development.

Surgical morbidity associated with administration of targeted molecular therapies before cytoreductive nephrectomy or resection of locally recurrent renal cell carcinoma.

PURPOSE: Targeted molecular therapies such as bevacizumab, sunitinib and sorafenib before surgical resection hold promise as rational treatment paradigms for patients with metastatic or locally recurrent renal cell carcinoma. To analyze the safety of this approach we evaluated surgical parameters and perioperative complications in patients treated with targeted molecular therapies before cytoreductive nephrectomy or resection of retroperitoneal renal cell carcinoma recurrence, and compared them to a matched patient cohort who underwent up-front surgical resection. MATERIALS AND METHODS: We evaluated surgical parameters and perioperative complications in 44 patients treated with targeted molecular therapies before cytoreductive nephrectomy or resection of local renal cell carcinoma recurrence, and in a matched cohort of 58 patients who underwent up-front surgery. RESULTS: Cohorts of patients treated with preoperative targeted molecular therapy and initial surgical resection were matched in terms of clinical characteristics, burden of metastatic disease and number of adverse prognostic factors. A total of 39 complications occurred in 17 (39%) patients treated with preoperative targeted molecular therapy and in 16 (28%) who underwent up-front resection (p = 0.287). There were no statistically significant differences in surgical parameters, incidence of perioperative mortality, re-exploration, readmission, thromboembolic, cardiovascular, pulmonary, gastrointestinal, infectious or incision related complications between patients treated with preoperative targeted molecular therapy and those who underwent up-front surgery. Duration, type and interval from targeted molecular therapy to surgical intervention were not associated with the risk of perioperative morbidity. CONCLUSIONS: Preoperative administration of targeted molecular therapies is safe, and does not increase surgical morbidity or perioperative complications in patients treated with cytoreductive nephrectomy or resection of recurrent retroperitoneal renal cell carcinoma.