Tesis

Gambaran Profile Molekuler Dan Kontrol Lokal Pasien Kanker Kolon Menggunakan Analisis Polymerase Chain Reaction (PCR) – High Resolution Melting (HRM) = Molecular Profile and Local Control of Colon Cancer Patients using Polymerase Chain Reaction–High Resolution Melting (PCR–HRM) Analysis.

Pendahuluan: Kanker kolon merupakan salah satu penyebab utama kematian akibat kanker di Indonesia. Profil molekuler, khususnya mutasi pada gen RAS dan PI3K, berperan penting dalam menentukan respon terapi serta luaran klinis. Penelitian ini bertujuan untuk menggambarkan profil molekuler pasien kanker kolon dan hubungannya dengan kontrol lokal pasca terapi. Metode: Penelitian deskriptif-analitik ini menggunakan 20 sampel jaringan kanker kolon hasil operasi reseksi di RSUPN Cipto Mangunkusumo (2022). DNA diekstraksi dari jaringan FFPE dan dianalisis menggunakan PCR–High Resolution Melting (HRM) untuk mendeteksi status MSI, metilasi MLH1, serta mutasi BRAF, KRAS (ekson 2 dan 3), NRAS (ekson 3), dan PIK3CA (ekson 9 dan 20). Hubungan profil molekuler dengan kontrol lokal dievaluasi menggunakan uji Fisher Exact. Hasil: Pemeriksaan berhasil pada rata-rata 90 % sampel. Mutasi terbanyak terdapat pada KRAS ekson 3 (35 %), diikuti NRAS ekson 3 (10 %) dan KRAS ekson 2 (5 %). Seluruh status MSI satbil (MSS) dan tidak ditemukan mutasi BRAF, PIK3CA, atau metilasi MLH1. Tidak terdapat hubungan bermakna antara profil molekuler dan kontrol lokal (p > 0,05), meskipun terdapat kecenderungan bahwa mutasi KRAS ekson 3 berhubungan dengan risiko progresi lokal lebih tinggi (OR 4,44; 95 % CI 0,62–32,07). Kesimpulan: Mutasi KRAS, terutama pada ekson 3, merupakan kelainan molekuler tersering dan berpotensi memengaruhi kontrol lokal pasien kanker kolon. Pemeriksaan molekuler berbasis HRM dapat digunakan sebagai langkah awal penapisan mutasi gen KRAS untuk membantu penentuan strategi terapi yang tepat.
Kata kunci: kanker kolon, KRAS, profil molekuler, PCR-HRM, kontrol lokal


Background: Colorectal cancer is one of the leading causes of cancer-related mortality in Indonesia. Molecular alterations, particularly mutations in the RAS and PI3K pathways, play a major role in determining treatment response and clinical outcome. This study aimed to describe the molecular profile of colorectal cancer patients and its association with local control after therapy. Methods:This descriptive-analytic study included 20 formalin-fixed paraffinembedded (FFPE) colorectal cancer specimens obtained from surgical resections at Cipto Mangunkusumo National General Hospital (2022). DNA was extracted and analyzed using polymerase chain reaction–high resolution melting (PCRHRM) to detect MSI status, MLH1 promoter methylation, and mutations in BRAF, KRAS (exons 2 & 3), NRAS (exon 3), and PIK3CA (exons 9 & 20). The association between molecular profile and local control was evaluated using Fisher’s exact test. Results: PCR-HRM analysis was successful in approximately 90 % of samples. The most frequent alteration was KRAS exon 3 mutation (35 %), followed by NRAS exon 3 (10 %) and KRAS exon 2 (5 %). All MSI status are stabile (MSS) and no mutations were detected in BRAF or PIK3CA, and no MLH1 methylation was observed. There was no significant association between molecular profile and local control (p > 0.05); however, patients with KRAS exon 3 mutations tended to have poorer local control (OR 4.44; 95 % CI 0.62–32.07). Conclusion: KRAS exon 3 mutation was the most common molecular alteration and may influence local control in colorectal cancer. PCR-HRM-based molecular testing can serve as an initial screening tool for KRAS mutation to guide personalized therapeutic strategies.
Keywords: colon cancer, KRAS, molecular profile, PCR-HRM, local control