Background:
Colorectal cancer (CRC) remains one of the leading causes of cancer-related morbidity and mortality worldwide. Systemic inflammation is known to influence tumor progression and recurrence. Hematological parameters derived from routine complete blood count (CBC), such as hemoglobin level, leukocyte count, platelet count, and inflammatory indices including neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR), may reflect tumor–host interactions and have potential prognostic value. This study aimed to evaluate the association between hematological changes and recurrence status among colorectal cancer patients treated in a tertiary referral hospital.

Methods:
This observational analytical study used a cross-sectional design based on secondary data from medical records of colorectal cancer patients treated between January 2020 and December 2024 in a tertiary referral hospital in Indonesia. Patients aged ≥18 years with histopathologically confirmed colorectal cancer and available preoperative CBC results were included. Hematological parameters analyzed included hemoglobin, leukocyte count, platelet count, neutrophil count, lymphocyte count, NLR, and PLR. Hematological abnormalities were categorized as presence or absence of hematological changes. Disease-free survival status was classified into recurrence and no recurrence. Statistical analysis was performed using the Fisher exact test with a significance level of p < 0.05.

Results:
A total of 32 patients were included with a mean age of 56.4 ± 11.2 years; 62.5% were male. The mean hemoglobin level was 12.7 ± 2.2 g/dL, leukocyte count 8.3 ± 2.1 ×10³/µL, platelet count 320.6 ± 128.4 ×10³/µL, NLR 3.1 ± 1.6, and PLR 189.4 ± 92.7. During follow-up, 18 patients (56.3%) remained disease-free and 14 patients (43.7%) developed recurrence. Hematological changes were observed in 19 patients (59.4%) and were significantly associated with recurrence status (p = 0.028).

Conclusion:
Hematological changes derived from routine CBC parameters were significantly associated with recurrence status in colorectal cancer patients. These parameters may serve as accessible indicators for identifying patients at risk of recurrence, although further studies with larger cohorts are needed to confirm their prognostic value.