The comparison of oxaliplatin or irinotecan rechallenge treatment with regorafenib in the third-line treatment of metastatic colorectal cancer

INTRODUCTION: In this study, we aimed to compare the results of regorafenib with those of oxaliplatin or irinotecan based rechallenge therapy as the third-line treatments for metastatic colorectal cancer (mCRC).
METHODS: Between January 2010 and December 2017, data of 427 mCRC patients were evaluated retrospectively. Sixty one mCRC patients who received regorafenib (n: 21) or rechallenge therapy (n: 40) as third-line setting were included.
RESULTS: Median follow-up was 7.1 months (range; 2.2–41.6). While no complete response was observed in any of our patients, the partial response was 17% in the rechallenge group and 5% in the regorafenib group (p=0.2). In the Rechallenge group, the median OS was 9.6 months (95% CI 7.3–13.3), while in the regorafenib group 7 months (1.9–17) there was no statistically significant difference (HR: 1.05; 95% CI 0.5–2.1, p=0.9). Median progression-free survival (PFS) was similar in both groups (4.7 and 3.1 months, HR: 1.45; 95% CI 0.82–2.5, p=0.1). Although median PFS (6.7 months and 4 months, p = 0.4) and OS (10.3 and 7.1 months, p = 0.1) were numerically better in treatment free-interval (TFI) ≥6 months group, this difference was not statistically significant.
DISCUSSION AND CONCLUSION: According to our findings, regorafenib with rechallenge treatment is similar activity. Based on these data, rechallenge therapy in this patient group with poor prognosis may be an alternative treatment option in the third step or a regimen that can be preferred in the next steps in the patients who are scheduled with the recommended treatments. However, due to the small number of our patients and the retrospective nature of our study, prospective randomized trials with large number of patients are needed in this area.

Metastatik kolorektal kanserin üçüncü basamak tedavisinde oksaliplatin veya irinotekan rechallenge tedavi ile regorafenib karþýlaþtýrmasý

GÝRÝÞ ve AMAÇ: Bu çalýþmada iki basamak standart tedavi almýþ metastatik kolorektal kanser (mKRK) tanýlý hastalarda oksaliplatin ya da irinotekan bazlý rejimlerin yeniden verildiði (rechallenge) hastalar ile regorafenib alan hastalarýn gerçek yaþam verilerinin karþýlaþtýrýlmasý amaçlandý.
YÖNTEM ve GEREÇLER: Ocak 2010 ve Aralýk 2017 tarihleri arasýnda merkezimizde mKRK tanýsýyla takip edilen 427 hastanýn verileri retrospektif olarak deðerlendirilip, iki basamak stardart kemoterapi sonrasý progresyon nedeniyle rechallenge kemoterapi (n: 40) veya regorafenib (n: 21) alan 61 hasta çalýþmaya alýndý.
BULGULAR: Medyan takip süresi 7.1 aydý (aralýk; 2.2–41.6). Hiçbir hastamýzda tam yanýt gözlenmez iken parsiyel yanýt rechallenge grubunda %17, regorafenib grubunda ise %5 olarak bulundu (p=0.2). Rechallenge grubunda ortanca genel saðkalým (GSK) 9.6 ay (%95 CI 7.3–13.3) iken regorafenib grubunda 7 ay (1.9–17) olup istatistiksel olarak fark yoktu (Hazard oraný [HR]: 1.05; %95 Güven aralýðý [GA] 0.5–2.1, p=0.9). Ortanca progresyonsuz saðkalým da (PSK) her iki grupta benzerdi (sýrasýyla; 4.7 ay ve 3.1 ay, HR: 1.45; 95% GA 0.82–2.5, p=0.1). Rechallenge grubundaki hastalar önceki tedavilerinde tedavisiz süre (TS) <6 ay ve ≥6 ay olarak ayrýldýðýnda TS ≥6 ay olan grupta ortanca PSK (sýrasýyla 6.7 ay ve 4 ay, p=0.4) ve GSK (10.3 ve 7.1 ay, p=0.1) numerik olarak daha iyi olsa da bu fark istatistiksel olarak anlamlý deðildi.
TARTIÞMA ve SONUÇ: Bulgularýmýza göre rechallenge tedavi ile regorafenib benzer etkinliktedir. Bu verilere dayanarak kötü prognozlu olan bu hasta grubunda rechallenge tedavi üçüncü basamakta alternatif bir tedavi seçeneði veya önerilen tedaviler ile progrese olan hastalarda sonraki basamaklarda tercih edilebilecek bir rejim olabilir. Ancak hasta sayýmýzýn azlýðý ve çalýþmamýzýn retrospektif olmasý nedeniyle bu konuda çok sayýda hasta içeren prospektif çalýþmalara ihtiyaç vardýr.