Decisions on Further Research for Predictive Biomarkers of High-Dose Alkylating Chemotherapy in Triple-Negative Breast Cancer: A Value of Information Analysis

OBJECTIVES

To inform decisions about the design and priority of further studies of emerging predictive biomarkers of high-dose alkylating chemotherapy (HDAC) in triple-negative breast cancer (TNBC) using value-of-information analysis.

METHODS

A state transition model compared treating women with TNBC with current clinical practice and four biomarker strategies to personalize HDAC: 1) BRCA1-like profile by array comparative genomic hybridization (aCGH) testing; 2) BRCA1-like profile by multiplex ligation-dependent probe amplification (MLPA) testing; 3) strategy 1 followed by X-inactive specific transcript gene (XIST) and tumor suppressor p53 binding protein (53BP1) testing; and 4) strategy 2 followed by XIST and 53BP1 testing, from a Dutch societal perspective and a 20-year time horizon. Input data came from literature and expert opinions. We assessed the expected value of partial perfect information, the expected value of sample information, and the expected net benefit of sampling for potential ancillary studies of an ongoing randomized controlled trial (RCT; NCT01057069).

RESULTS

The expected value of partial perfect information indicated that further research should be prioritized to the parameter group including "biomarkers' prevalence, positive predictive value (PPV), and treatment response rates (TRRs) in biomarker-negative patients and patients with TNBC" (€639 million), followed by utilities (€48 million), costs (€40 million), and transition probabilities (TPs) (€30 million). By setting up four ancillary studies to the ongoing RCT, data on 1) TP and MLPA prevalence, PPV, and TRR; 2) aCGH and aCGH/MLPA plus XIST and 53BP1 prevalence, PPV, and TRR; 3) utilities; and 4) costs could be simultaneously collected (optimal size = 3000).

CONCLUSIONS

Further research on predictive biomarkers for HDAC should focus on gathering data on TPs, prevalence, PPV, TRRs, utilities, and costs from the four ancillary studies to the ongoing RCT.

[A comparative study of thio-tepa and mitomycin C in the treatment of pterygium. Preliminary results]

AIMS

To compare the efficacy of Thio-tepa and Mitomycine C to obviate recurrence; to compare cost-efficacy ratios; to evaluate their facility of use and their complications.

METHODS

In a prospective blinded study, 36 patients undergoing surgery for 46 primary and recurrent pterygium were assigned randomly to three groups: group 1 received 0.02 mg/ml of Mitomycine C three times daily for 5 days; group 2 received Thio-tepa four times daily for 6 weeks, group 3 served as a control receiving distilled water three times daily for five days.

RESULTS

Recurrence rates were 38%, in group 1; 28% in group 2; 82% in group 3 respectively. Follow-up ranged from 15 to 44 weeks (mean 27.93 +/- 8.9 weeks). Mean delay recurrence time was 6.3 weeks. Topical Mitomycin caused: iritis, conjunctival irritation, excessive lacrymation, photophobia, ocular pain; Thio-tepa caused: photophobia, foreign body sensation, headache.

CONCLUSIONS

Mitomycine C appears to be an effective and safe adjunctive treatment for this cost-efficacy and this facility of use comparison.