Radiation Therapy Combined with (or without) Cisplatin-based Chemotherapy for Patients with Nasopharyngeal Cancer: 15-years Experience of a Single Institution in Korea / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: This retrospective study was carried out to evaluate the efficacy and toxicity of radiation therapy (RT) with/without cisplatin-based chemotherapy in nasopharyngeal cancer (NPC). MATERIALS AND METHODS: One hundred forty six patients with NPC received curative RT and/or cisplatin-based chemotherapy. Thirty-nine patients were treated with induction chemotherapy (IC), including cisplatin and 5-fluorouracil followed by RT. Another 63 patients were treated with concurrent chemoradiotherapy (CCRT) using cisplatin, and 22 patients were treated with IC followed by CCRT. The remaining 22 patients were treated with RT alone. RESULTS: One hundred four (80.0%) patients achieved complete response (CR), and 23 (17.7%) patients achieved partial response (PR). The patterns of failure were: locoregional recurrences in 21.2% and distant metastases in 17.1%. Five-year overall survival (OS) and progression free survival (PFS) were 50.7% and 45.0%, respectively. Multivariate Cox stepwise regression analysis revealed CR to chemoradiotherapy to be a powerful prognostic factor for OS. CR to chemoradiotherapy and completion of radiation according to the time schedule were favorable prognostic factors for PFS. A comparison of each treatment group (IC --> RT vs. CCRT vs. IC --> CCRT vs. RT alone) revealed no significant differences in the OS or PFS. However, subgroup analysis showed significant differences in both OS and DFS in favor of the combined chemoradiotherapy group compared with RT alone, for stage IV and T3-4 tumors. Grade 3-4 toxicities were more common in the combined chemoradiotherapy arm, particularly in the CCRT group. CONCLUSIONS: This study was limited in that it was a retrospective study, much time was required to collect patients, and there were imbalances in the number of patients in each treatment group. Combined chemoradiotherapy remarkably prolonged the OS and PFS in subgroup patients with stage IV or T3-4 NPC.

Mutation of p53 Gene and Detection of Human Papillomavirus DNA in Larynx and Pharynx Cancers / 대한이비인후과학회지

Mutations in the p53 tumor suppressor gene have been shown to be one of the most common genetic abnormalities in human cancers. Loss of p53 tumor suppressor gene function can occur through gene mutation or interaction with early proteins of oncogenic viruses such as E6 protein of human papillomaviruses(HPV). We studied 24 squamous cell carcinomas of the larynx(20) and hypopharynx(4) for p53 gene mutations as well as for the presence of oncogenic HPV DNA. Exon 5 through 8 of the p53 gene were examined using polymerase chain reaction-direct sequencing methods. HPV detection was done using polymerase chain reaction amplification with HPV L1 consensus primer. HPV type was determined by the same method using HPV-16 and -18 type-specific E6 primers. The results were as follows: 1) Eight of 24 tumors(33%) had p53 mutations, one of which had 2 mutational sites. All cases of which had p53 mutations or HPV DNA detection were larynx cancer. 2) p53 genetic alteration in larynx cancer included seven missense mutations resulting in single amino acid substitutions, one nonsense mutation encoding a stop codon and one silent mutation. Six of 9(66.7%) mutations occurred in two distinct regions of the genes, codon 245-248(3 mutations) and codon 283-294(3 mutations). 3) The p53 mutational spectrum observed was characterized by G to T transversion(4 of 9), T to A transversion(2 of 9), C to A transversion(1 of 9), G to A transition(1 of 9) and C to T transition(1 of 9). 4) HPV DNA was detected in 3 of 24(12.5%) tumors. According to the type of HPV DNA, HPV-16 was detected in 1 case and HPV non-16, -18 was detected in 2 cases, one of which had p53 mutation. 5) There was no relationship between p53 mutations or HPV DNA detection and clinicopathologic parameters. These results suggest that p53 mutations may play an important role in carcinogenesis of laryngeal cancer. Further study is necessary to clarify the role of p53 mutation and oncogenic HPV infection on clinical outcome of laryngeal cancer.