Latar belakang : Toksisitas hematologi sering terjadi pada pasien dengan Kanker Paru Karsinoma Bukan Sel Kecil (KPKBSK) yang diobati dengan kemoterapi berbasis platinum. Data sebelumnya menunjukkan bahwa trombositopenia karena kemoterapi berbasis karboplatin adalah rendah tetapi tidak ada data lokal yang menjelaskan angka kejadian trombositopenia pada KPKBSK yang diterapi dengan regimen karboplatin+gemsitabin. Tujuan dari penelitian ini adalah untuk melihat dan membandingkan angka kejadian toksisitas hematologi seperti trombositopenia, anemia, leucopenia, neutropenia dan perdarahan yang disebabkan kemoterapi karboplatin+gemsitabin dengan karboplatin+paklitaksel dan karboplatin+etoposid pada pasien KPKBSK. Dan juga membandingkan respons objektif dari ketiga regimen tersebut. Metode:. Penelitian ini kohort retrospektif pada pada pasien KPKBSK yang menerima 1.250 mg/m2 gemsitabin pada hari ke-1 dan hari ke-8 dan karboplatin AUC-5(Area under curve) hari pertama. Pasien yang menerima ≥ 2 siklus ikut dalam penelitian ini. Kami menilai dan membandingkan toksisitas hematologi tiap siklus seperti trombositopenia, anemia, leucopenia, neutropenia dan perdarahan serta respons objektif dari ketiga regimen berbasis karboplatin selama kemoterapi. Hasil: Pada penelitian ini didapatkan total 115 pasien (rerata umur 55.6±10, rerata jumlah siklus adalah 4, jenis histologi adenokarsinoma 91%, stage III or IV) Pasien KPKBSK yang menerima regimen karboplatin+gemsitabine (n=38), karboplatin+paklitaksel (n=39) dan karboplatin+etoposid (n=38). Angka kejadian trombositopenia regimen karboplatin+gemsitabin adalah 34.2%, karboplatin+paklitaksel 5.1%, dan karboplatin+etoposid 5.3%. Waktu terjadinya trrombositopenia pada regimen karboplatin+gemsitabin 2 siklus lebih cepat dari regimen lain. Toksisiti hematologi trombositopenia regimen karboplatin+gemsitabin sebesar 15,8% dengan grade 3-4, leukopenia 18,4% dengan grade 3- 4 dan anemia 5,3% grade 3-4. Overall respons rate dan time to progression dengan regimen karboplatin+gemsitabin lebih baik dari regimen lainnya. Kesimpulan : Angka kejadian dan waktu terjadinya toksisitas hematologi pada regimen karboplatin+gemsitabin lebih tinggi daripada regimen karboplatin+paklitaksel dan karboplatin+etoposid.. Tetapi Overall respons rate dan time to progression pada karboplatin+gemsitabin lebih baik daripada regimen lain. Background : Hematological toxicities often occur in patients with non-small-cell lung cancer (NSCLC) who are treated with chemotherapy. In our data had shown that thrombocytopenia due to carboplatin based chemotherapy was low but there was not any local data about carboplatin - gemcitabine regimen. The aim of this study is to investigate and to compare the frequency of hematologic events, such as thrombocytopenia, anemia, leucopenia, neutropenia, and hemorrhage due to combination of gemcitabine-carboplatin with carboplatin-paclitaxel, and carboplatin-etoposide in non-small cell lung cancer patients. And also to compare objective response of the three platinum based regimens. Methods : We conducted a retrospective cohort study that enrolled all non-small-cell lung cancer patients who received 1.250 mg/m2 gemcitabine on day 1,8 and AUC-5 carboplatin on day one. Patients who received 2 cycles or more are included in this study. We investigated and compared objective response of the three platinum based regimens and the frequency of thrombocytopenia, anemia, leucopenia, neutropenia, hemorrhage, during chemotherapy period. Results : A total 115 patients (mean age 55.6±10, median number of cycle of chemotherapy was 4, histological findings were adenocarcinoma 91%) with stage III or IV NSCLC received chemotherapy carboplatin-gemcitabine (n=38), carboplatin-paclitaxel (n=39) and carboplatin-etoposide (n=38). Frequency of thrombocytopenia in patients with NSCLC treated with combination of carboplatin-gemcitabin regimen was 34.2%, carboplatin-paclitaxel 5.1%, and carboplatin-etoposide 5.3%. The Carbo-gemcitabine group developed thrombocytopenia 1 or 2 cycles earlier than other group . The hematological toxicities data with carbo-gemcitabine regimen have shown that thrombocytopenia was 15,8% patient with grade 3 or 4, leucopenia 18,4% patients with grade 3 or 4 and 5,3% grade 3 or 4 anemia. Overall respons rate and time to progression with carboplatin-gemcitabine regimen were better than the other regimens Conclusion : Thrombocytopenia was found in gemcitabine and carboplatin regimen but lower than other published data. Overall respons rate and time to progression with carboplatin-gemcitabine regimen were better than the other regimens.