RESUMEN
BACKGROUND: K-RAS and recently N-RAS gene mutation testing are mandatory requirements prior to anti-epidermal growth factor receptor (EGFR) monoclonal antibody treatment of metastatic CRC. Mutation prevalence and distribution in Indonesian colorectal cancer (CRC) are not known. METHODS: Combined methods of PCR high-resolution melt (HRM), restriction fragment length polymorphism (RFLP), and direct DNA sequencing were used to genotype exons 2, 3, and 4 of both K-RAS and N-RAS genes for routine clinical testing of CRC patients. Descriptive analytical review of 595 consecutive CRC patients (years 2013 to 2016) was performed to find associations between gene mutations and clinicopathologic features. RESULTS: This retrospective study revealed overall K-RAS gene mutation in exon 2 (codon 12 and 13) rates being 34.9%. Women (42.5%), stages I and II (43.4%), and well and moderate differentiations (37.7%) had higher frequency of K-RAS exon 2 mutations than men (29%, p = 0.006), stages (III and IV 31.9%, p = 0.05), and poor differentiation (11.8%, p = 0.002), respectively. At later period (2015-2016), 121 of 595 patients were genotyped for the remaining exons 3 and 4 of K-RAS as well as exons 2, 3, and 4 of N-RAS mutations resulting in overall RAS mutation prevalence of 41%. Mucinous histology had highest frequency of N-RAS mutation. CONCLUSIONS: Combination of PCR HRM with either RFLP or direct DNA sequencing was useful to detect K-RAS exon 2 and extended RAS mutations, respectively. Frequency of all RAS mutations in stage IV Indonesian (41%) was similar among Asians (41-49%), which tend to be lower than western (55%) CRC.
Asunto(s)
Neoplasias Colorrectales/enzimología , Neoplasias Colorrectales/genética , Mutación , Proteínas Proto-Oncogénicas p21(ras)/genética , Adolescente , Adulto , Anciano , Estudios de Cohortes , Neoplasias Colorrectales/epidemiología , Femenino , Humanos , Indonesia/epidemiología , Masculino , Persona de Mediana Edad , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Adulto JovenRESUMEN
PURPOSE: We sought to evaluate prevalence, age-adjusted distribution, and impact of single and multiple high- and low-risk human papillomavirus (HPV) subtypes and their associations with cervical lesions. METHODS: Data were extracted from 11,224 women who underwent routine screening of HPV genotyping and liquid-based cytology co-testing. Fifteen high-risk (HR) and six low-risk (LR) HPV types were genotyped. RESULTS: Overall HPV prevalence was 10.7 %, and young women (under 21 years old) harbored highest HPV infection rate (40.38 %). The rate declined in old women 9.49 % (age 30-49) and 6.89 % (age 50 and above). Normal cytology had lowest HPV (5.66 %) compared to low-grade (60.49 %), high-grade (71.96 %) squamous intraepithelial lesions (LSIL and HSIL) and squamous cell carcinoma SCC (86.9 %). LR HPV subtypes were absent in SCC and were consistently lower than HR HPV in LSIL (6.74 vs. 33.54 %) and HSIL (2.12 vs. 51.32 %). Multiple HPV infection was more frequent in young women under 30 years old (10 %) than older women (2 %) and in LSIL (20.2 %), HSIL (18.5 %) than SCC (4.4 %). HR HPV 52, 16, 18, and 58 were the most frequent subtypes in normal, LSIL, and HSIL. Greater or equal proportion of HPV 16, 18, 45, and 52 was found in SCC compared to normal cytology (SCC/normal ratios 4.8, 1.2, 1.6, and 1.7). While important in LSIL and HSIL, HPV58 was not detected in SCC. CONCLUSION: Taken together, identification of these HPV types, especially HPV 16, 18, 45, and 52, and their associated cervical lesions may improve cervical cancer preventive strategies in Indonesia.