Mean platelet volume/platelet count ratio in combination with tumor markers in colorectal cancer: a retrospective clinical study

BACKGROUND: Mean platelet volume (MPV) is a marker of platelet activation, which is usually negatively correlated with platelet count (PC). The ratio of MPV to PC (MPV/PC) has an essential role in the diagnosis of multiple malignancies. However, only a few studies investigated the value of MPV/PC in colorectal cancer (CRC) and the combination of MPV/PC with tumor markers in CRC. This retrospective clinical study aimed to evaluate the diagnostic value of MPV/PC and tumor markers (CA72-4, CA125, CA199) used alone or in combination in CRC. METHODS: 200 patients with CRC and 317 patients with colorectal benign polypus pathologically diagnosed during 2019/01/04 to 2022/06/30 were included. Hematological and pathological parameters of the above patients were collected, data were analyzed with Student’s t-test, one-way ANOVA or Kruskal-Wallis H test and receiver operating characteristic (ROC) curve, and ROC curve was used to evaluate the diagnostic value of tumor markers and MPV/PC used alone or in combination in CRC. RESULTS: The MPV/PC in CRC group was significantly lower than the control group (P < 0.0001). Among the three tumor markers, higher CA125 was correlated with distant metastasis and lower differentiation (P < 0.05), increased CA72-4 indicated positive nerve invasion (P = 0.0174), and elevated CA199 was associated with lymphatic metastasis and positive vascular invasion (P < 0.05). For subgroups regarding tumor anatomical location, both CA125 and CA199 were higher in colon cancer group than rectum cancer group (P = 0.0322, P = 0.0094). MPV/PC was associated with tumor infiltration, regional lymph node metastasis, differentiation and nerve invasion (P < 0.05) and the combination of MPV/PC with the three tumor markers produced a larger AUC with higher sensitivity, specificity and Yuden index than MPV/PC or the three tumor markers used alone to distinguish between CRC and colorectal polyps. CONCLUSION: Preoperative MPV/PC in peripheral blood of patients with CRC was lower than the control group. Meanwhile, the combined detection of tumor markers with MPV/PC can improve the diagnostic value of CRC, revealing the potential of MPV/PC as a promising screening tool in CRC early diagnosis.