Published online Jun 21, 2014. doi: 10.3748/wjg.v20.i23.7480
Revised: December 14, 2013
Accepted: January 8, 2014
Published online: June 21, 2014
AIM: To determine the prevalence and characteristics of additional primary malignancies in gastric cancer (GC) patients.
METHODS: GC patients (862 total; 570 men, 292 women; mean age 59.8 ± 12.8 years) diagnosed at the Department of Gastroenterology at Pomeranian Medical University over a period of 23 years were included in this retrospective analysis of a prospectively maintained database. Mean follow-up time was 31.3 ± 38.6 mo (range 1-241 mo). The following clinicopathological features of patients with synchronous tumors were compared to those with metachronous tumors: age, sex, symptom duration, family history of cancer, tumor site, stage (early vs advanced), histology, and blood group. GC patients with and without a second tumor were compared in terms of the same clinicopathological features.
RESULTS: Of 862 GC patients, 58 (6.7%) developed a total of 62 multiple primary tumors, of which 39 (63%) were metachronous and 23 (37%) synchronous. Four (6.9%) of the 58 multiple GC patients developed two or more neoplasms. The predominant tumor type of the secondary neoplasms was colorectal (n = 17), followed by lung (n = 9), breast (n = 8), and prostate (n = 7). Age was the only clinicopathological feature that differed between GC patients with synchronous vs metachronous malignancies; GC patients with synchronous neoplasms were older than those with metachronous neoplasms (68.0 ± 10.3 years vs 59.9 ± 11.1 years, respectively, P = 0.008). Comparisons between patients with and without a second primary cancer revealed that the only statistically significant differences were in age and blood group. The mean age of the patients with multiple GC was higher than that of those without a second primary tumor (63.4 ± 11.4 years vs 59.5 ± 13.0 years, respectively, P = 0.026). GC patients with a second primary tumor were more commonly blood group O than those without (56.2% vs 31.6%, respectively, P = 0.002).
CONCLUSION: GC patients may develop other primary cancers; appropriate preoperative and postoperative diagnostic modalities are thus required, particularly if patients are older and blood group O.
Core tip: In our study, the incidence of second primary malignancies in gastric cancer (GC) patients was 6.7%. The predominant tumor type of the secondary neoplasms was colorectal cancer, followed by lung, breast, and prostate. GC patients with synchronous neoplasms were older than those with metachronous neoplasms. GC patients with second primary tumors were significantly more likely to be blood group O and older than those without. This suggests a need for additional procedures, such as colonoscopy, chest X-ray, mammography and computed tomography, particularly for those who are older and blood group O.