Urachal carcinoma: a large retrospective multicentric study from the French Genito-Urinary Tumor Group.

Introduction: Urachal cancer (UrC) is a rare, non-urothelial malignancy. Its natural history and management are poorly understood. Although localized to the bladder dome, the most common histological subtype of UrC is adenocarcinoma. UrC develops from an embryonic remnant, and is frequently diagnosed in advanced stage with poor prognosis. The treatment is not standardized, and based only on case reports and small series. This large retrospective multicentric study was conducted by the French Genito-Urinary Tumor Group to gain a better understanding of UrC. Material and Methods: data has been collected retrospectively on 97 patients treated at 22 French Cancer Centers between 1996 and 2020. Results: The median follow-up was 59 months (range 44-96). The median age at diagnosis was 53 years (range 20-86), 45% were females and 23% had tobacco exposure. For patients with localized disease (Mayo I-II, n=46) and with lymph-node invasion (Mayo III, n=13) median progression-free-survival (mPFS) was 31 months (95% CI: 20-67) and 7 months (95% CI: 6-not reached (NR)), and median overall survival (mOS) was 73 months (95% CI: 57-NR) and 22 months (95% CI: 21-NR) respectively. For 45 patients with Mayo I-III had secondary metastatic progression, and 20 patients were metastatic at diagnosis. Metastatic localization was peritoneal for 54% of patients. Most patients with localized tumor were treated with partial cystectomy, with mPFS of 20 months (95% CI: 14-49), and only 12 patients received adjuvant therapy. Metastatic patients (Mayo IV) had a mOS of 23 months (95% CI: 19-33) and 69% received a platin-fluorouracil combination treatment. Conclusion: UrC is a rare tumor of the bladder where patients are younger with a higher number of females, and a lower tobacco exposure than in standard urothelial carcinoma. For localized tumor, partial cystectomy is recommended. The mOS and mPFS were low, notably for patients with lymph node invasion. For metastatic patients the prognosis is poor and standard therapy is not well-defined. Further clinical and biological knowledge are needed.

Association of cabozantinib pharmacokinetics, progression and toxicity in metastatic renal cell carcinoma patients: results from a pharmacokinetics/pharmacodynamics study.

BACKGROUND: Cabozantinib is a tyrosine kinase inhibitor with a substantial efficacy in metastatic renal cell carcinoma, and is associated with a challenging toxicity profile leading to frequent drug discontinuations. Whereas an exposure/safety relationship was demonstrated for this drug, an exposure/efficacy relationship is still unknown. PATIENTS AND METHODS: We carried out a monocentric, observational, pharmacokinetics/pharmacodynamics (PK/PD) study in patients with metastatic renal cell carcinoma (INDS MR 5612140520). We used measured blood concentrations of cabozantinib (Cmeas) to determine the area under the curve (AUC), apparent clearance (Cl/F) and residual blood concentration (Ctrough). Best overall response according to RECIST 1.1 and relevant toxicity (adverse event grade 3-4 or grade 2 requiring dose reduction or discontinuation) were assessed according to Cmeas, Ctrough, AUC and Cl/F. RESULTS: We enrolled 76 patients, including 35 who experienced disease progression and 30 with grade 3-4 toxicity. Patients with progressive disease had a significantly lower median Ctrough (406 versus 634 ng/ml, P = 0.001), Cl/F (2 versus 2.9 l/h, P = 0.002) and AUC (16 versus 20 µg h/ml, P = 0.037) compared with patients who had disease control as best response. Patients with relevant toxicity had a significantly higher Cmeas (732 versus 531 ng/ml, P = 0.006), Ctrough (693 versus 521 ng/ml, P = 0.005) and AUC (21 versus 16 µg h/ml, P = 0.046) compared with patients who did not experience any grade relevant toxicity. Receiver operating characteristic curves obtained from our study defined a threshold for drug efficacy of 536.8 ng/ml and of 617.7 ng/ml for toxicity. CONCLUSION: We first demonstrate the PK/PD relationship for cabozantinib. Severe toxicities are associated with a higher drug exposure, whereas inefficacy is associated with a lower drug exposure. Cabozantinib plasma drug monitoring may be useful to optimize clinical practice.

Prognosis of renal cell carcinoma with bone metastases: Experience from a large cancer centre.

BACKGROUND: Bone metastases (BMs) are associated with significant morbidity and shorter survival in renal cell carcinoma (RCC). Our purpose was to identify prognostic factors for overall survival (OS) in RCC patients with BMs. METHODS: Data from patients with BMs from RCC treated at Gustave Roussy between April 1992 and March 2016 were retrospectively collected. Age, sex, Eastern Cooperative Oncology Group-Performance Status, Memorial Sloan-Kettering Cancer Center (MSKCC) risk groups, histology, number and site of bone lesions, concomitant metastases (presence and sites), therapy for BMs (radical resection or palliative surgery, radiotherapy and other local and systemic treatments) and time from diagnosis to BMs were analysed. Synchronous solitary bone metastasis (SSBM) was defined as a single BM without concomitant visceral lesions at the initial diagnosis of RCC. OS was calculated from the date of BMs diagnosis to death or last follow-up using Kaplan-Maier method and modelled with Cox regression analysis. RESULTS: From 1750 patients with diagnosis of RCC followed at Gustave Roussy Cancer Campus, 300 patients with BMs were identified. Median time from diagnosis to BMs was 32.4 months (range 0-324 months). In 64 patients (21%), bone was the only metastatic site, and 22 patients (7%) had an SSBM and 236 patients (79%) had concomitant metastases in other sites. Median OS was 23.2 months (95% confidence interval 19.9-26.2). SSBM patients had better OS than those with concomitant metastases (40 vs 20 months; P < 0.001). At multivariate analysis, concomitant metastases remained predictor of poor prognosis, while MSKCC risk group, radical resection and SSBM were predictors of better OS. CONCLUSIONS: This study suggests that MSKCC score, numbers of BMs and radical resection are important prognostic factors for RCC patients with BMs. Additionally, in the presence of solitary BM without concomitant metastases at the initial diagnosis of RCC, bone surgery should be considered to achieve local tumour control and likely increase OS.