# The Impact of Carboplatin Dosing Design Using Adjusted Serum Creatinine on Carboplatin Plus Paclitaxel Therapy for Ovarian Cancer

## TL;DR

Adjusting serum creatinine values when calculating carboplatin doses in ovarian cancer chemotherapy may help maintain treatment intensity in dose-dense regimens.

## Contribution

The study evaluates the impact of SCr adjustment on dose intensity in different TC regimens for ovarian cancer.

## Key findings

- Adjusting SCr in dose-dense TC increased paclitaxel dose intensity and reduced treatment modifications.
- No significant differences were observed in tri-weekly TC regimens with or without SCr adjustment.
- SCr adjustment did not compromise carboplatin dose intensity in dose-dense TC.

## Abstract

Carboplatin (CBDCA) is a mainstay of chemotherapy for ovarian cancer and its dose is determined in proportion to the estimated creatinine clearance (CCr). Serum creatinine (SCr) values necessary to estimate CCr vary by measurement method: adding 0.2 mg/dL to SCr by enzymatic methods commonly used in Japan equates to SCr calculated using the Jaffe method, which is widely adopted outside Japan. Although adjustment by adding 0.2 mg/dL to SCr by enzymatic methods may avoid the potential overdose of CBDCA, its impact on the dose intensity (DI) of chemotherapy is unclear.

We retrospectively studied patients with ovarian cancer treated with CBDCA + paclitaxel (PTX) (TC) after primary surgery. Patients were classified into Cohort A (dose‐dense [dd‐]TC, SCr‐adjusted, n = 18), B (dd‐TC, non‐adjusted, n = 8), C (tri‐weekly [tw‐]TC, SCr‐adjusted, n = 6), and D (tw‐TC, non‐adjusted, n = 15), and DI and DI‐related measures including average relative DI (ARDI, [RDI of CBDCA + RDI of PTX]/2]) known to correlate with patients’ prognoses were compared.

Although the DI of CBDCA did not differ between Cohorts A and B, the DI of PTX and proportion of patients with ARDI ≥ 85% were higher in Cohort A than B (78 vs. 13%, p = 0.002) as a result of less frequent treatment modification. There was no difference in these measures between Cohorts C and D.

Adjustment of SCr when calculating the CBDCA dose did not compromise the DI of total CBDCA and may rather contribute to maintaining DI in patients receiving dd‐TC.

This retrospective study aimed to assess the impact of adjusting serum creatinine (SCr) values when determining carboplatin (CBDCA) doses in ovarian cancer chemotherapy. Patients treated with CBDCA + paclitaxel (TC) were categorized based on the regimen they received (dose‐dense TC or tri‐weekly TC) and whether or not their SCr levels were adjusted. Our findings suggest that in patients receiving dose‐dense TC, but not in those receiving tri‐weekly TC, adjusting SCr did not compromise the dose intensity of total CBDCA and may contribute to maintaining dose intensity, highlighting potential benefits in reducing treatment modification and adverse events.