Changing trends in the proportions of small (≤2 cm) proximal and non-proximal gastric carcinomas treated at a high-volume tertiary medical center in China

Objective Guided by the recently established histological criteria of the gastroesophageal junction (GEJ), we aimed to investigate and compare trends in the proportions of small (≤2 cm) proximal gastric carcinoma (PGC) vs non-PGC (NPGC) in Chinese patients over an 8-year period. Methods The study was conducted with consecutive surgical resected specimens of small PGC that was located within 3 cm below the GEJ and NPGC (located at all other gastric regions) treated at a single medical center in China. Differences in proportions between the two groups were compared. Results Among all 313 cases, 111 (35.5%) were classified as PGC and the remaining 202 (64.5%) as NPGC. Patients with PGC were significantly elder than those with NPGC, and none aged younger than 40 years. The proportions of PGC significantly and progressively increased from 16% in 2004 to 45% in 2011, in contrast to a steady decreasing trend for NPGC from 84% to 55% over the same period. The difference in trends between the two groups approached, but was not at a statistically significant level (P = 0.08). Proportions of small cancers in the gastric corpus and in female patients remained low and stable, in contrast to a significantly higher proportion in male patients (P < 0.05). Conclusions Our data showed a significantly upward-shifting trend in the proportions of small PGC, primarily in elderly male patients, in contrast to a downward shifting trend in NPGC over the most recent 8-year period in Chinese patients.