Comparing Clinical Characteristics and Outcomes of Young-onset and Late-onset Colorectal Cancer: An International Collaborative Study.

BACKGROUND: Compared with the general population, the incidence of young-onset (YO) colorectal cancer (CRC) is increasing. However, a significant knowledge gap exists in the clinical characteristics, treatment patterns, and outcomes for these patients. MATERIALS AND METHODS: Six international tertiary cancer centers conducted a retrospective study. Patients with YO CRC (aged 18-44 years) and LO CRC (aged > 44 years) diagnosed with histologically proven colorectal adenocarcinoma from June 2003 to June 2014 were enrolled. Patients were randomly chosen from each center's database, and the patient demographics and treatment information were collected. The data were then centralized, and the final analysis was performed at a single institution. Cox proportional hazards models were used to estimate the crude and adjusted hazard ratios (HRs) with 95% confidence intervals (CIs) for progression-free survival and mortality, and YO was compared with LO. Site-specific HRs were pooled using a random-effects meta-analysis. RESULTS: Overall, 498 patients, including 224 with YO (129 men; mean age, 37 ± 5.5 years) and 274 with LO (167 men; mean age, 64.8 ± 9.5 years) CRC, were included. At the diagnosis, 137 patients (61.2%) and 122 patients (44.5%) with YO and LO CRC had metastatic disease, respectively. For both cohorts, the 3 most common presenting symptoms were pain, hematochezia, and weight loss. Surgery was performed in 141 YO (63.0%) and 219 LO (79.9%) patients. The longitudinal noncurative treatment patterns were similar, but more biologic therapy was used for these YO patients. The pooled progression-free survival analysis results for first-line noncurative treatment favored LO (HR, 1.96; 95% CI, 1.04-3.68). The mortality analysis showed no significant differences between the 2 groups (YO: HR, 1.53; 95% CI, 0.91-2.58). CONCLUSION: Despite similar treatment patterns and survival outcomes, YO disease might be clinically more aggressive.

Loss of heterozygosity of tumor suppressor genes (p16, Rb, E-cadherin, p53) in hypopharynx squamous cell carcinoma.

OBJECTIVE: Microsatellite alterations, especially those that cause loss of heterozygosity (LOH), have recently been postulated as a novel mechanism of carcinogenesis and a useful prognostic factor in many kinds of malignant tumors. However, few studies have focused on a specific site, hypopharynx. The aim of this study was to evaluate the relationship between LOH and hypopharyngeal squamous cell carcinoma (HPSCC). STUDY DESIGN: Laboratory-based study. SETTING: Integrated health care system. SUBJECTS AND METHODS: Matched normal and cancerous tissues from 30 patients with HPSCC were examined for LOH in 4 tumor suppressor genes (TSGs) (p16, Rb, E-cadherin, and p53) at loci 9p21, 13q21, 6q22, and 17p13, respectively, using microsatellite markers amplified by polymerase chain reaction. The results for each loci were compared with clinicopathological features. RESULTS: Among the 30 cases, 26 (86.7%) exhibited LOH, with the most common alteration being LOH at p53 (52.6%). Significantly higher rates of LOH detection were seen in Rb, p53, and the LOH-high group (cases where 2 or more loci with LOH were found) in cases of lymph node metastasis. Compared with stage I and II carcinoma, tumors of stages III and IV had significantly higher frequencies of LOH in Rb, p53, and the LOH-high group. However, the presence of LOH was not significantly correlated with survival. CONCLUSION: These results suggest that LOH in TSGs such as Rb and p53 may contribute to the development and progression of HPSCC. The presence of LOH in the primary tumor may also be predictive of lymph node metastasis.