Presenter: A. Bamias Presenter's Affiliation: Hellenic Cooperative Oncology Group Type of Session: Scientific
Urothelial carcinoma is a relatively common cancer with a significant risk of disease progression and spread. Untreated disease-free survival rates are quite low, generally below 5%. The application of M-VAC chemotherapy (methotrexate, vinblastine, adriamycin and cisplatin) is currently considered standard of care, resulting in response rates of over 50%, median survival of > 1 year, and 3-year survival of 20-25%, for inoperable or metastatic cases. The M-VAC regimen has been shown to be superior to the CISCA regimen as well as cisplatin alone. However, it is a markedly toxic treatment with neutropenic sepsis rates as high as 10% and treatment-related mortality on the order of 3-4%. Increases in efficacy might be achieved through the addition of novel chemotherapy agents (ie: navelbine, gemcitabine) to M-VAC or through dose-intensification of standard M-VAC. Conversely, toxicity might be reduced via the administration of concurrent growth factors (ie: G-CSF).
Two studies have reported on the use of docetaxel and cisplatin (DC) chemotherapy in advanced urothelial carcinoma and found response rates of 52-60%, median survival of 8-13.6 months, and grade 3/4 hematologic toxicity rates as low as 33% (Sengelov et al, 1998; Dimopoulos et al, 1999). The purpose of this randomized phase III trial was to compare M-VAC + G-CSF to DC + G-CSF in patients with advanced urothelial carcinoma.
Materials and Methods
224 pts entered on study
220 randomized: M-VAC every 4 weeks (n=109) vs. DC every 3 weeks (n=111)
Completed tx as per protocol: M-VAC (n=103) vs. DC (n=104)
Baseline characteristics well-balanced on 2 arms EXCEPT for more favorable performance status on M-VAC arm
Stratified for presence of visceral metastases and prior chemotherapy (neo- or adjuvant)
Intent to treat analysis
Primary endpoint of overall survival (OS)
Secondary endpoints of time-to-progression (TTP), toxicity and response rates (RR)
Median follow-up = 13 mos
Median survival was 14.2 months for M-VAC vs 9.3 months for DC
Median time to progression was 9.4 months vs 6.1 months
2-yr survival was 28.6% vs 18.9
Complete response was 22.9% vs 13.2%
On initial analysis, OS, TTP and median survival all statistically significant
On multivariate analysis, performance status and visceral metastases were independent prognostic factors. When these factors were adjusted for, OS benefit lost statistical significance, but TTP remained significant.
Both arms were well tolerated overall.
- Hematologic grade 3/4 toxicity relatively infrequent overall but more common in M-VAC arm
- neutropenia 36.4% vs. 22.4%
- thrombocytopenia 12.6% vs. 1%
- neutropenic infections 6.9% vs. 1%
- 3 tx-related deaths from sepsis: 2 in M-VAC arm, 1 in DC
M-VAC is superior to DC as first line therapy in advanced urothelial malignancy.
Only time-to-progression showed statistically significant improvement in M-VAC group on multivariate analysis.
Overall survival effect was likely a result of the performance status imbalance between the treatment arms.
Use of G-CSF appeared to reduce toxicity of both chemotherapy regimens.
M-VAC with G-CSF support should be considered the standard of care for inoperable or metastatic urothelial carcinoma.
The current standard of care in advanced stage bladder carcinoma patients is M-VAC chemotherapy. The results of this study show a longer time-to-progression of disease with M-VAC as compared to a combination docetaxel-cisplatin regimen, further establishing the value of M-VAC. Although the authors did not demonstrate overall survival benefit on multivariate analysis, the smaller number of patients in this analysis likely lacked statitical power to detect a survival benefit. The data from this trial are consistent with 2 other studies (von der Maan et al and Sternberg et al) using M-VAC in advanced urothelial cancer; median survival rates, time-to-progression and response rates in those two studies are all comparable to those seen here. However, less toxicity was seen in this trial, and the authors attribute this to the use of G-CSF. However, whether or not this mandates a change in management standards to incorporate G-CSF to all M-VAC regimens in advanced cases remains to be seen. What is known is that there is certainly room for improvement in the side effect profile of this efficacious chemotherapy regimen, and G-CSF may very well be one answer.
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Feb 2, 2012 - Radium-223 chloride improves overall survival (OS) for men with castration-resistant prostate cancer (CRPC) bone metastases; and MDV3100 improves OS for men with CRPC who have progressed following docetaxel-based chemotherapy, according to two phase III studies presented at the annual American Society of Clinical Oncology's Genitourinary Cancers Symposium, held from Feb. 2 to 4 in San Francisco.