Clinicopathologic characteristics and survival rate in patients with synchronous or metachronous double primary colorectal and gastric cancer

• Published in: Korean journal of clinical oncology Vol. 14; no. 2; pp. 83 - 88
• Main Authors: Park, Ji-Hyeon, Baek, Jeong-Heum, Yang, Jun-Young, Lee, Won-Suk, Lee, Woon-Kee
• Format: Journal Article
• Language: English
• Published: 대한종양외과학회 01.12.2018; Korean Society of Surgical Oncology
• Subjects: colorectal neoplasm; multiple primary neoplasms; second primary neoplasm; stomach neoplasm; 일반외과학; Multiple primary neoplasms; Second primary neoplasm; Colorectal neoplasm; Stomach neoplasm
• ISSN: 1738-8082; 2288-4084
• DOI: 10.14216/kjco.18015

Purpose Double primary colorectal cancer (CRC) and gastric cancer (GC) represent the most common multiple primary malignant tumors (MPMT) in Korea. The recognition and screening of hidden malignancies other than the primary cancer are critical. This study aimed to investigate the clinicopathologic characteristics and survival rates in patients with synchronous or metachronous double primary CRC and GC. Methods Between January 1994 and May 2018, 11,050 patients were diagnosed with CRC (n=5,454) or GC (n=5,596) at Gil Medical Center. MPMT and metastatic malignant tumors were excluded from this study. A total of 103 patients with double primary CRC and GC were divided into two groups: the synchronous group (n=40) and the metachronous group (n=63). The incidence, clinicopathologic characteristics, and survival rate of the two groups were analyzed. Results The incidence of synchronous and metachronous double primary CRC and GC was 0.93%. Double primary CRC and GC commonly occurred in male patients aged over 60 years with low comorbidities and minimal previous cancer history. There were significant differences between the synchronous and metachronous groups in terms of age, morbidity, and overall survival. Metachronous group patients were 6 years younger on average (P=0.009), had low comorbidities (P=0.008), and showed a higher 5-year overall survival rate (94.8% and 61.3%, P<0.001) in contrast to synchronous group. Conclusion When primary cancer (CRC or GC) is detected, it is important to be aware of the possibility of the second primary cancer (GC or CRC) development at that time or during follow-up to achieve early detection and better prognosis.