Important side effect of zoledronic acid treatment in metastatic breast cancer: renal failure

Objective: Renal failure is one of the most prominant adverse effect of the zoledronic acid (ZA) which is well known to decrease the skeletal-related events (SREs) in breast cancer patients developing bone metastasis. In this particular study, our object was to evaluate the incidence of this side effect and the risk factors leading to the development of renal failure.
Material and Method: A total of 97 patients who underwent ZA treatment for breast cancer with bone metastasis in our institute between March 2006 and December 2013 were evaluated. For the assesment of renal failure, serum creatinine levels were obtained before the treatment. Preliminary and the highest levels of creatinine levels during the treatment were used in calculation of creatinine clearance according to the Crockcroft-Gault formula. The age of the patients, the number ZA treatment periods, number of the infusions, the simultaneous anti-cancer treatments, non-steroidal anti-inflammatory drug use, diabetes mellitus and presence of hypertension were recorded.
Results: The mean age of the patients was 54±10 years and the treatment period of ZA was 37±18 months. In all of the patients participated in this study the preliminary creatinine levels were under 1.4 mg/dl. In 22 of our patients (23%) creatinine levels increased more than 0.5 mg/dL, besides creatinine clearance were found out to be decreased both of which were pointing out the renal toxicity. In two patients creatinine clearance was under 30 ml/min. and one of the patients has undergone renal dialysis. The only independent risk factor underlined was the advanced age (60 years ≤) (p=0.017).
Conclusion: As a conclusion breast cancer patients with bone metastasis undergoing ZA treatment are prone to the development of renal failure. In order to avoid this particular risk of developing renal failure, serum creatinine levels should strictly be monitored before the treatment and meticulous attention to the hydration should be given during the treatment especially in patients with advanced age.

Metastatik meme kanserinde zoledronik asit tedavisinin önemli bir yan etkisi: Renal yetmezlik

Amaç: Kemik metastazý geliþen meme kanserli hastalarda kemiðe baðlý olay (SRE) geliþimini azalttýðý bilinen zoledronik asitin (ZA) en önemli yan etkilerinden biri renal yetmezlik geliþimidir. Bizim bu çalýþmadaki amacýmýz, bu yan etkinin sýklýðýný ve geliþimini etkileyen risk faktörlerini deðerlendirmektir.
Gereç ve Yöntem: Ýstanbul Florence Nightingale Çalýþma Grubu arþivinde yer alan ve Mart 2006-Aralýk 2013 tarihleri arasýnda ZA tedavisi verilen kemik metastazlý 97 meme kanseri hastasý çalýþmamýza dahil edilmiþtir. Renal yetmezlik deðerlendirmesi için, serum kreatinin seviyesi her tedavi öncesi ölçülüp, baþlangýç ve en yüksek kreatinin deðerleri alýnarak, Crockcroft-Gault formülüne göre kreatinin klirensi hesaplanmýþtýr. Hastalarýn yaþý, ZA kullaným süresi, ZA infüzyon sayýsý, eþzamanlý antikanser tedaviler, nonsteroidal antiinflamatuar ilaç kullanýmý, diabetes mellitus ve hipertansiyon varlýðý kaydedilmiþtir.
Bulgular: Ortalama hasta yaþý 54±10 yýl ve ortalama ZA kullanýmý süresi 37±18 ay olarak bulundu. Baþlangýç kreatinin deðeri tüm hastalarda 1.4 mg/dL’nin altýnda idi. 22 hastamýzda (%23) kreatinin deðerinde 0.5 mg/dL’nin üzerinde artýþ olup, kreatinin klirensinde düþüþ saptanmýþ ve renal toksisite olarak deðerlendirilmiþtir. Ýki hastamýzda kreatinin klirensi <30 ml/min. düþmüþ ve 1 hastamýzda diyaliz ihtiyacý olmuþtur. Renal yetmezlik geliþimi için tek baðýmsýz risk faktörü ileri yaþ (60≤) olarak saptanmýþtýr (p=0.017).
Sonuç: Sonuç olarak, metastatik meme kanserli hastalarda ZA kullanýmý sýrasýnda karþýlaþýlabilecek en önemli sorunlardan biri renal yetmezliktir. Bu riski azaltmanýn en önemli yolu her tedavi öncesi serum kreatinin kontrolü ve özellikle ileri yaþ hasta grubunda hidrasyona dikkat etmektir.