AbstrakLarge cell carcinoma (LCC) merupakan suatu udifferentiated non-small cell carcinoma adalah subtipe dari kanker paru yang tidak dijumpai gambaran small cell carcinoma (SCLC), adenocarcinoma (ADC), maupun squamous cell carcinoma (SQC). Aplikasi sitologi paru yang relevan saat ini adalah dalam mendiagnosa dan penanganan kanker paru. Sekitar 70% kanker paru didiagnosis pada stadium lanjut dan tidak dapat diobati.Pada artikel ini, dilaporkan gambaran sitologi dari LCC. Laporan kasus seorang pria usia 54 tahun yang secara klinis diduga karsinoma bronkus, kemudian dilakukan brushing bronkus. Pemeriksaan sitologi menunjukkan kelompokan sel-sel tumor yang hiperseluler, membentuk pola syncytia-like sheets, dengan batas antar sel tidak jelas. Sel-sel tumor pleomorfik, dijumpai giant sel, inti bulat sampai irregular, beberapa dijumpai binukleasi, kromatin kasar, anak inti menonjol, sitoplasma eosinofilik. Hasil pemeriksaan sitologi suatu LCC. Prognosa umumnya buruk, reseksi komplet pada stadium I atau II, angka ketahanan hidup diperkirakan berkisar antara 0%-21%. Kata kunci : large cell carcinoma, kanker paru, undifferentiated non-small cell carcinoma, sitologi. AbstractLarge cell carcinoma (LCC) as an undifferentiated non-small cell carcinoma is a merely descriptive term indicating a subtype of lung cancer with no specific features of small-cell lung cancer (SCLC), adenocarcinoma (ADC) or squamous cell carcinoma (SQC). The most relevant application of lung cytology today is in the diagnosis and management of lung cancer; approximately 70% of those cancers are diagnosed at a late stage and are unresectable. We investigated the cytology smear of large cell carcinoma. The case report of a 54 years old man, clinically diagnosed with suspected carcinoma bronchus. The cytology features from brushing bronchus showed hypercellularity of cell tumor arranged in cellular aggregates or syncytia-like sheets of large cells with indistinct cell borders. The cells are extreme pleomorphisme, bizarre tumor giant cells, nuclei round to irregular, sometimes binuclei with vesicular chromatin and prominent nucleoli, with eosinosophilic cytoplasm. The result of cytology evaluated were Large Cell Carcinoma. The prognosis was poorly, completely resection of stage I or II, the survival rate was estimated to range between 0% to 21%. Key words: large cell carcinoma, lung cancer, undifferentiated non-small cell carcinoma, cytology.