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Colorectal cancer (CRC) is the fourth most common carcinoma with an increasing incidence in China [1]. In addition, comparing to solitary tumors, synchronous colorectal carcinoma (synchronous CRC) is a rare type of colorectal malignancy, which is defined as more than one primary colorectal carcinoma detected in one patient at the time of initial presentation [2]. The range of prevalence is 1.1%–8.1% of all colorectal cancers [3]. Synchronous CRC is often seen in males, and a previous large-scale study determined the male/female ratio as 1.85 [4]. The other known higher risk factors include inflammatory bowel diseases, Lynch syndrome, familial adenomatous polyposis, and adenomas/hyperplasic polyposis [5–8]. Moreover, the chromosomal instability, microsatellite instability (MSI), and gene methylation account for various predisposing lesions or factors for synchronous CRC [9]. Although synchronous CRC is identified as a significant entity at the clinical and molecular level, the clinical and pathological features and prognosis are yet controversial [5]. In addition, the results of previous studies which evaluated the prognostic significance of synchronous CRC are conflicting. Thus, the common consensus is reached on the occurrence of synchronous CRC as an independent predictive factor of survival as compared to solitary CRC after the operation [5,10,11]; the expected long-term survival rates of patients with synchronous CRC are yet controversial [12]. The present study aimed to compare the various clinicopathological features and short-term/long-term cancer-specific outcomes between synchronous and solitary CRC by a matched pair analysis with stratification based on age, sex, American Society of Anesthesiologists (ASA) class, BMI, cancer grade, tumor location, and tumor stage.