Esophageal cancer constitutes a global public health challenge. However, South Korean population-specific information on the association of lifestyle (smoking, alcohol consumption, and obesity status) with esophageal cancer risk is sparse. This nested case–control study analyzed the Korean national health screening cohort data (2002–2019) of 1114 patients with esophageal cancer and 4456 controls (1:4 propensity-score matched for sex, age, income, and residential region). Conditional and unconditional logistic regression analyses, after adjustment for multiple covariates, determined the effects of lifestyle factors on esophageal cancer risk. Smoking and alcohol consumption increased the esophageal cancer risk (adjusted odds ratio [95% confidence interval]: 1.37 [1.15–1.63] and 1.89 [1.60–2.23], respectively). Overweight (body mass index [BMI] ≥ 23 to <25 kg/m²), obese I (BMI ≥ 25 to <30 kg/m²), or obese II (BMI ≥ 30 kg/m²) categories had reduced odds of esophageal cancer (0.76 [0.62–0.92], 0.59 [0.48–0.72], and 0.47 [0.26–0.85], respectively). In the subgroup analyses, the association of incident esophageal cancer with smoking and alcohol consumption persisted, particularly in men or those aged ≥55 years, whereas higher BMI scores remained consistently associated with a reduced esophageal cancer likelihood across all age groups, in both sexes, and alcohol users or current smokers. Underweight current smokers exhibited a higher propensity for esophageal cancer. In conclusion, smoking and alcohol drinking may potentially increase the risk, whereas weight maintenance, with BMI ≥ 23 kg/m², may potentially decrease the risk, for esophageal cancer in the South Korean population. Lifestyle modification in the specific subgroups may be a potential strategy for preventing esophageal cancer.

Although safety concerns regarding proton pump inhibitor (PPI)/H2-receptor antagonists (H2RA) in the incident esophageal cancer have been raised, the Asian-based report is unclear. We investigated the estimated likelihood of incident esophageal cancer—its mortality depending on prior history of PPI/H2RA use—and gastroesophageal reflux disease (GERD) in Koreans. Using the Korean National Health Insurance Service-Health Screening Cohort data (2002–2015), a case–control study was retrospectively conducted, including 811 patients with incident esophageal cancer and 3244 controls matched with sex, age, income, and residence. Propensity score overlap weighting was adjusted to balance the baseline covariates. Overlap propensity score-weighted logistic regression analyses were assessed to determine associations of the prior exposure of PPI/H2RA (current vs. past) and the medication duration (<30-, 30–90-, vs. ≥90-days) with incident esophageal cancer and its mortality among the total participants or those with/without the GERD episodes, after adjusting for multiple covariates including PPI/H2RA. The current exposure to either PPI or H2RA showed higher odds for incident esophageal cancer than the nonuser group ([13.23; 95%CI 10.25–17.06] and [4.34; 95%CI 3.67–5.14], respectively), especially in all adults over the age of 40 years without GERD. Both current and past exposures to PPI showed a decreased probability of mortality compared with those of the nonuser group ([0.62; 95%CI 0.45–0.86] and [0.41; 95%CI 0.25–0.67], respectively). However, current or past exposure to H2RA harbored the mutually different likelihoods for mortality depending on the presence of GERD and old age. This study carefully speculates on the possible link between PPI/H2RA and incident esophageal cancer in the Korean population. Mortality appears to be affected by certain risk factors depending on drug types, exposure history, old age, and the presence of GERD.

Limited data are available on the diagnostic utility of circulating tumor DNA (ctDNA) in early-stage thyroid cancers for BRAF, KRAS, NRAS, and TERT promoter mutations, which are known detectable markers for thyroid cancers. Here, we analyzed the above driver mutations in ctDNA and matched neoplastic tissues from patients with early-stage thyroid cancers in order to investigate diagnostic utility of circulating markers in distinguishing from other mimicking thyroid lesions and healthy individuals. In total, 73 matched neoplastic tissue and plasma samples [thyroid cancers (n = 62), benign thyroid disorders (n = 8), and parathyroid lesions (n = 3)] and 54 plasma samples from healthy individuals (as controls) were analyzed for BRAF, KRAS, NRAS, and TERT promoter mutations using peptide nucleic acid clamp real-time PCR. Although only one patient with an indeterminate lesion on thyroid cytology showed KRAS mutation (codon 146) in the preoperative plasma, that KRAS mutation was not identified in the stage I papillary thyroid carcinoma tissue. In the remaining 72 plasma samples, no other mutations were identified in BRAF, NRAS, and TERT promoter genes. The concordance rates of mutational results between the plasma and tumor tissue or metastatic lymph node were very low. One (1.9%) of the 54 healthy individuals harbored a KRAS mutation in the plasma samples. The ctDNA results did not represent the mutational profile of primary or metastatic thyroid cancers, warranting a caution for interpretation. The clinical utility of BRAF, KRAS, NRAS, and TERT promoter mutation analysis on ctDNA appears to be limited to early-stage thyroid cancers.

Jun Tae Yang, M.D., Hyoung Soo Kim, M.D., Ph.D., Kun Il Kim, M.D., Ph.D., Ho Hyun Ko, M.D., Jung Hyun Lim, M.D., Hong Kyu Lee, M.D., Yong Joon Ra, M.D.. J Chest Surg 2022;55:452-61. https://doi.org/10.5090/jcs.22.052

Gu BM, et al. J Korean Med Sci. 2025 Aug;40(36):e233. https://doi.org/10.3346/jkms.2025.40.e233

Bong Suk Park, M.D., Won Yong Lee, M.D., Ph.D., Yong Joon Ra, M.D., Hong Kyu Lee, M.D., Byung Mo Gu, M.D., Jun Tae Yang, M.D.. Korean J Thorac Cardiovasc Surg 2020;53:1-7. https://doi.org/10.5090/kjtcs.2020.53.1.1