Pregled odmerjanja protitumornih zdravil pri bolnikih s prekomerno telesno težo na Onkološkem Inštitutu Ljubljana

Šribar, Anja (author), Vovk, Tomaž (mentor), Rožman, Samo (comentor)

Večina odmerkov zdravil, ki se uporabljajo za sistemsko zdravljenje rakavih obolenj je odvisna od telesne površine oziroma telesne teže posameznega bolnika. Smernice zdravljenja narekujejo uporabo dejanske telesne teže oziroma dejanske telesne površine za izračun odmerkov tudi pri bolnikih s prekomerno telesno težo, saj dokazov, da bi večji odmerki povečali tveganje za toksičnost zdravil, ni. Z raziskavo smo preverili ustreznost odmerjanja protitumornih zdravil za sistemsko zdravljenje onkoloških bolnikov s povečano telesno težo, ki so se v letih 2017 in 2018 zdravili na Onkološkem inštitutu Ljubljana (OIL). Pregledali smo tudi, kako pogosto se tekom zdravljenja spremlja telesna teža bolnikov. V raziskavo smo vključili bolnike, ki so se v letih 2017 in 2018 zdravili s sistemskim zdravljenjem na OIL in so imeli vrednost indeksa telesne mase (ITM) 35 kg/m2 ali več ter so tekom zdravljenja prejeli vsaj en odmerek, ki je bil za 10 % ali več znižan od priporočenega odmerka. Podatke o bolnikih smo dobili iz interne podatkovne baze lekarne OIL, podatke o predpisanih protokolih zdravljenja, priporočenih in predpisanih odmerkih iz programa za naročilo in pripravo protitumornih zdravil CYPRO, pojasnila za znižanje odmerkov pa v medicinskem informacijskem sistemu WebDr in povzetkih glavnih značilnosti zdravil. Izmed 270 bolnikov, ki so imeli ITM 35 kg/m2 ali več je 97 bolnikov (36 %) prejelo vsaj en odmerek, ki je bil za 10 % ali več znižan od priporočenega. Med njimi je bilo 65 žensk (67 %) in 32 moških (33 %). Pri ženskah je bila najpogosteje postavljena diagnoza rak dojke – v 27 primerih (42 %), pri moških pa rak debelega črevesa in danke – v 10 primerih (32 %). Na začetku zdravljenja je znižan odmerek prejelo 64 od 270 bolnikov (24 %) z ITM 35 kg/m2 ali več. Razlogi za znižanje odmerkov na začetku zdravljenja so bili slabo splošno stanje bolnikov, slabša jetrna funkcija, slabša ledvična funkcija ali pa je bilo definiranih več različnih razlogov. Pri 43 bolnikih (67 %) razloga za znižanje odmerkov na začetku zdravljenja ni bilo navedenega, zato zanje sklepamo, da je debelost vplivala na odmerke protitumornih zdravil. Pri 17 od 43 bolnikov je bila za izračun odmerkov uporabljena idealna telesna teža oziroma idealna telesna površina. Med zdravljenjem je znižan odmerek prejelo 39 bolnikov, kar predstavlja 14 % vseh bolnikov z ITM 35 kg/m2 ali več. Odmerki so bili med zdravljenjem največkrat znižani zaradi izraženih neželenih učinkov (59 %), preostali razlogi pa so bili slabša jetrna in ledvična funkcija, zapleti med zdravljenjem in poslabšanje splošnega počutja. Pri tej skupini ni bilo navedenega razloga za znižanje odmerkov pri šestih bolnikih (15 %), zato sklepamo, da je na znižanje odmerkov vplivala povišana telesna teža teh bolnikov. Debelost je na znižanje odmerkov na začetku zdravljenja in med zdravljenjem vplivala pri skupno 49 bolnikih, kar predstavlja 18 % vseh onkoloških bolnikov z ITM 35 kg/m2 ali več. Obstaja možnost, da debelost ni vplivala na znižanje odmerkov pri teh bolnikih, vendar bi za dodatno razlago potrebovali več podatkov. Obdobje zdravljenja daljše od šestih mesecev smo določili pri 54 bolnikih. Štirje bolniki (7 %) so imeli telesno težo spremljano redno, torej vsaj enkrat mesečno. Preostalim bolnikom se je telesna teža izmerila v daljših obdobjih, devetim bolnikom (17 %) pa telesna teža v obdobju zdravljenja v letih 2017 in 2018 ni bila izmerjena niti enkrat.

• Language: Slovenian
• Keywords: rak, debelost, protitumorna zdravila, odmerjanje, nižanje odmerkov, meritve telesne teže
• Work type: Master's thesis/paper
• Organization: FFA - Faculty of Pharmacy
• Year: 2020
• PID: 20.500.12556/RUL-114408
• Publication date in RUL: 27.02.2020

Secondary language

• Language: English
• Title: Overview of anticancer drugs dosing in obese patients at the Institute of Oncology Ljubljana

Abstract

Most of the anticancer drugs dosing used for systemic cancer treatment depend on body surface area or body weight of each patient. Treatment guidelines imply that actual body weight and actual body surface area should be used also in obese patients since there is no evidence that full weight-based dosing increases the toxicity of the drugs. Our study reviewed the adequacy of administered doses of anticancer drugs used for systemic cancer treatment in obese patients treated at the Institute of Oncology Ljubljana in years 2017 and 2018. We also reviewed the frequency of the body weight measurements. The study included patients who were treated at the Institute of Oncology Ljubljana in years 2017 and 2018, had their body mass index 35 kg/m2 or greater and received at least one dose that was reduced for 10 % or more from the prescribed dose. We collected patients' data from the internal data base of the Pharmacy Department at the Institute of Oncology Ljubljana, information about prescribed treatment protocols, prescribed and recommended doses in CYPRO programme and explanations for reducing doses in WebDr programme and Summaries of Product Characteristics. 97 patients of 270 patients (36 %) with their body mass index 35 kg/m2 or greater received at least one dose that was reduced for 10 % or more from the recommended dose. Among them there were 65 women (67 %) and 32 men (33 %). The most common diagnosis in women was breast cancer – 27 patients (42 %) and colorectal cancer in men – 10 patients (32 %). 64 patients received reduced dose at the beginning of treatment which represents 24 % of all patients in the study. Reasons for reducing doses were weak general state of the patients, liver and kidney dysfunction or there were more different reasons identified. In 43 patients (67 %) of the cases there were no reasons applied for reduced doses therefore we assume that obesity impacted the dosing of anticancer drugs in these patients. In 17 of 43 patients ideal body weight or ideal body surface area was used for calculating the doses. During the treatment 39 patients received reduced doses, which represents 14 % of all patients in the study. The most common reason for dose reductions during the treatment were adverse effects of the treatment (59 %). Other reasons were liver and kidney dysfunction, weak general state and other complications that appeared during treatment. In six patients (15 %) doses were reduced with no listed reasons and for these patients we believe that the obesity was the reason for the reduction. Altogether obesity impacted dose reductions in 49 patients which represent 18 % of all obese patients who were treated at the Institute of Oncology Ljubljana in years 2017 and 2018. There are potential other reasons for dose reductions in these patients, but we would need more information in order to determine them. Treatment period was longer than six months in 54 patients. Four patients (7 %) had their body weight measured regularly, meaning once per month or more often. Other patients had their body weight measured in periods that are longer than one month and in nine patients (17 %) body weight measurement was not performed even once in treatment periods in years 2017 and 2018.

• Keywords: cancer, obesity, anticancer drugs, dosing, reduced doses, body weight measurements