Postoperative Serum Levels of sCD26 for Surveillance in Colorectal Cancer Patients

Abstract

One of the main aims of the follow-up after curative resection of colorectal cancer is the early detection and treatment of tumor recurrence. We previously demonstrated decreased preoperative soluble CD26 (sCD26) levels in serum from colorectal cancer patients. We extended now the study to investigate if sCD26 levels in postoperative serum serve as marker of recurrence of the disease during surveillance. Soluble sCD26 was measured in pre- and postoperative serum samples of 43 patients with primary colorectal cancer. Carcinoembryonic antigen, carbohydrate antigen 19.9 and 72.4 levels were also measured during surveillance. The average follow-up period was 41.8±20.8 months. sCD26 levels during follow-up showed well-defined patterns in patients without disease (n = 28), and in patients with tumor persistence (n = 2), local recurrence (n = 3) or distant metastasis (n = 10). Disease-free patients showed stable levels between 460–850 ng/mL during follow-up, while high (over 850 ng/mL) and unstable sCD26 levels were found before recurrence was diagnosed. The mean maximum/minimum sCD26 ratios during surveillance were 1.52, 2.12 and 2.63 for patients with no recurrence, local recurrence and metastasis, respectively (p = 0.005). From the cut-off obtained from a receiver operator characteristics (ROC) curve built with the maximum/minimum sCD26 ratios and the upper and lower cut-offs of sCD26, we were able to discriminate patients with and without recurrent disease. We propose that the measurement of serum sCD26 during the follow-up of patients diagnosed of colorectal cancer could be valuable for the early detection of local and distant recurrence. A large, randomized, prospective trial should be performed to confirm our findings.

Serum dipeptidyl peptidase IV activity and sCD26 concentration in patients with choroidal nevus or uveal melanoma

“…Our previous reports indicated the potential usefulness of sCD26 as a biomarker for colorectal cancer, particularly in early diagnosis [5][6][7] and follow-up [8]. In the latter case, increased levels could be valuable for the early detection of local and distant recurrence [8], perhaps related to the presence of CD26-expressing CSCs [8,9].…”

“…Serum levels of soluble CD26 (sCD26) and its dipeptidyl peptidase activity (DPP-IV) have been proposed as biomarkers for lung and colorectal cancer screening including metastasis detection [5][6][7][8][9]. A pilot study was designed to check their potential for ocular cancer detection.…”

“…Diagnostic efficiency of serum sCD26 and DPP-IV levels was tested after finding that UM groups showed "anomalous" values only above a high cut-off provisionally constructed in the same way that sCD26 cut-offs [6][7][8]. A cut-off for specificity values close to 90%, as typically required in a screening setting, was selected by the ROC (data not shown).…”

Serum CD26 levels in patients with gastric cancer: A novel potential diagnostic marker

“…Also serum CD26 is substantially dysregulated in various cancers: serum CD26 levels are increased in patients with hepatic cancer and decreased in patients with blood, thyroid and oral cancers [10,11]. Recently, CD26 has been identified as a serum marker for colorectal cancer detection and prognostic factor [12][13][14] while to best of our knowledge no study investigated the role of serum CD26 in presence of gastric cancer.…”

“…In addition, serum DPP4 levels is increased in patients with hepatic cancer and decreased in patients with blood, solid and oral cancer [10,11]. Recently, CD26 has been identified as a serum marker for colorectal cancer detection [11][12][13] as well as a prognostic factor able to promote human colorectal cancer metastasis [14], while to best of our knowledge no study investigated the role of serum CD26 in gastric cancer. Only a previous study suggested that CD26 expression level in surgical samples may be considered a reliable biomarker of malignant GISTs of the stomach characterized by distinct clinical, genetic, and histopathological features [15].…”