Neutrophil-lymphocyte ratio (NLR) reflects the balance between pro- and anti-tumor immune activities. We evaluated whether NLR is associated with pathologic tumor response and prognosis in rectal cancer patients that underwent preoperative chemoradiaton therapy (CRT) with surgery. One hundred two patients with rectal cancer that were treated by preoperative CRT followed by surgery were enrolled. A total of 50.4 GY of radiation and 5-FU-based chemotherapy were delivered. An NLR ≥ 3 was considered to be elevated. Pathologic tumor response based on ypTNM stage was categorized into two groups, good response (n = 35, pathologic complete response and ypTNM I) and poor response groups (n = 67, ypTNM II, III, and IV). Twenty-five patients (24.5%) had elevated NLR. Multivariate analysis showed that an elevated CEA level (p = 0.001), larger tumor (p = 0.03), and elevated NLR (p = 0.04) were significant predictors for a poor response. Poor pathological tumor response and elevated NLR were risk factors for cancer-specific and recurrence-free survivals. An elevated NLR before CRT can be used as predictors for poor tumor response and unfavorable prognostic factors. Dominant pro-tumor activities of neutrophils or reduced anti-tumor immune response by lymphocytes, as determined by NLR, may have a impact on poor tumor response and unfavorable prognosis.

To evaluate factors affecting the use and delay ≥8 weeks of adjuvant chemotherapy and the impact of chemotherapy use and delay on survival. Between 2005 and 2012, consecutive patients with stage II and III colorectal cancer who were treated with major curative resection were enrolled. Among 750 patients with stage II (n = 318) and III (n = 432) disease, 153 (20.4%) did not receive chemotherapy. Among 597 patients with adjuvant chemotherapy, 31 (5.2%) began chemotherapy 8 weeks or more after surgery. Factors associated with not receiving chemotherapy were: age ≥80 years (hazard ratio [HR] = 5.2), American Society of Anesthesiologists score ≥3 (HR = 1.9), underlying cerebrovascular disease (HR = 1.7), stage II disease (HR = 2.0), presence of postoperative complications (HR = 2.2), or intensive care unit admission (HR = 2.4). Factors associated with chemotherapy delay ≥8 weeks were: male sex (HR = 4.2), rectal primary cancer (HR = 5.4), or presence of postoperative complications (HR = 2.5). Independent prognostic factors for overall survival included TNM III stage (HR = 2.04) and chemotherapy delay ≥8 weeks (HR = 0.39) or <8 weeks (HR = 0.22). Independent prognostic factors for recurrence-free survival were TNM III stage (HR = 2.26) and chemotherapy delay <8 weeks (HR = 0.35). Postoperative complications were associated with both lack of and delayed chemotherapy. Timely initiation of chemotherapy, defined as <8 weeks, was a favorable prognostic factor for overall and recurrence-free survival. To increase the proportion of patients receiving chemotherapy and timely initiation of chemotherapy, surgical complications should be minimized after curative resection.

For many years, developmental and physiological differences have been known to exist between anatomic segments of the colorectum. Because of different outcomes, prognoses, and clinical responses to chemotherapy, the distinction between right colon cancer (RCC) and left colon cancer (LCC) has gained attention. Furthermore, variations in the molecular features and gut microbiota between right and LCCs have recently been a hot research topic. CpG island methylator phenotype-high, microsatellite instability-high colorectal cancers are more likely to occur on the right side whereas tumors with chromosomal instability have been detected in approximately 75% of LCC patients and 30% of RCC patients. The mutation rates of oncogenes and tumor suppressor genes also differ between RCC and LCC patients. Biofilm is more abundant in RCC patients than LLC patients, as are Prevotella, Selenomonas, and Peptostreptococcus. Conversely, Fusobacterium, Escherichia/Shigella, and Leptotrichia are more abundant in LCC patients compared to RCC patients. Distinctive characteristics are apparent in terms of molecular features and gut microbiota between right and LCC. However, how or to what extent these differences influence diverging oncologic outcomes remains unclear. Further clinical and translational studies are needed to elucidate the causative relationship between primary tumor location and prognosis.

Factors associated with postoperative complications and 1-year mortality after surgery for colorectal cancer in octogenarians and nonagenarians Young Wan Kim, Ik Yong Kim Division of Colorectal Surgery, Department of Surgery, Yonsei University Wonju College of Medicine, Wonju, Korea Purpose: To identify the factors affecting 30-day postoperative complications and 1-year mortality after surgery for colorectal cancer in octogenarians and nonagenarians. Methods: Between 2005 and 2014, a total of 204 consecutive patients aged ≥80 years who underwent major colorectal surgery were included. Results: One hundred patients were male (49%) and 52 patients had American Society of Anesthesiologists (ASA) score ≥3 (25%). Combined surgery was performed in 32 patients (16%). Postoperative complications within 30 days after surgery occurred in 54 patients (26%) and 30-day mortality occurred in five patients (2%). Independent risk factors affecting 30-day postoperative complications were older age (≥90 years, hazard ratio [HR] with 95% confidence interval [CI] =4.95 [1.69-14.47], P=0.004), an ASA score ≥3 (HR with 95% CI =4.19 [1.8-9.74], P=0.001), performance of combined surgery (HR with 95% CI =3.1 [1.13-8.46], P=0.028), lower hemoglobin level (<10 g/dL, HR with 95% CI =7.56 [3.07-18.63], P<0.001), and lower albumin level (<3.4 g/dL, HR with 95% CI =3.72 [1.43-9.69], P=0.007). An ASA score ≥3 (HR with 95% CI =2.72 [1.15-6.46], P=0.023), tumor-node-metastasis (TNM) stage IV (HR with 95% CI =3.47 [1.44-8.39], P=0.006), and occurrence of postoperative complications (HR with 95% CI =4.42 [1.39-14.09], P=0.012) were significant prognostic factors for 1-year mortality. Conclusion: Patient-related factors (older age, higher ASA score, presence of anemia, and lower serum albumin) and procedure-related factors (performance of combined surgical procedure) increased postoperative complications. Avoidance of 30-day postoperative complications may decrease 1-year mortality. Keywords: colonic neoplasms, rectal neoplasms, laparoscopy, laparotomy, aged 80 years and above

We aimed to review whether pretreatment inflammatory markers reflect the short- and long-term outcomes of patients with colon cancer, rectal cancer, colon and rectal cancers, and metastatic colorectal cancer (CRC). We found that pretreatment complete blood count and blood chemistry tests reflect short-term and long-term oncological outcomes in patients with CRC. Specifically, in patients with colon cancer, hypoalbuminemia was associated with worse postoperative morbidity, mortality, and inferior survival. In patients with rectal cancer, elevated neutrophil-lymphocyte ratio (NLR) and thrombocytosis were associated with postoperative complications, poor overall survival (OS), and disease-free survival (DFS). A high C-reactive protein/albumin ratio (CAR) was associated with poor OS and DFS. In patients with metastatic CRC, increased NLR and platelet-lymphocyte ratio (PLR) were associated with poor OS, DFS, and progression-free survival (PFS). In addition, high CAR and a low albumin/globulin ratio on blood chemistry tests were associated with poor OS and PFS. Although universal cut-off values were not available, various types of pretreatment laboratory markers could be utilized as adjuncts to predict prognosis in patients with CRC.