Preoperative inflammation is an independent factor of worse prognosis after colorectal cancer surgery.

BACKGROUND: We know that inflammation is related to colorectal cancer prognosis and to the onset of postoperative infections. OBJECTIVE: This study aimed to understand the relationship between preoperative inflammation and the prognosis of colorectal cancer and to elucidate whether the impact of inflammation on cancer prognosis was related to an increased risk of surgical infection or was independent of it. METHODS: Patients who underwent elective colorectal cancer surgery between November 2011 and April 2014 were included in a prospective database (IMACORS). Preoperative c reactive protein was collected for each patient. Patients were followed up according to the French national guidelines. A cut-off of preoperative CRP of 5mg/L was chosen. Clinical characteristics were compared according to CRP using Chi2 and Mann-Whitney tests. The Overall Survival (OS) and Disease-Free-Survival (DFS) were compared by Kaplan-Meier curves. A Cox proportional hazards regression model was applied to perform a multivariate analysis of OS and DFS's predictors. RESULTS: A total of 254 patients were included. The median age was 68 years old. The median follow up was 41.8 months. The overall median preoperative CRP was 5mg/L. Preoperative CRP was significantly associated with N status; CRP being significantly higher among patients with colonic cancer and with patients who didn't receive a neoadjuvant treatment. Multivariate analyse revealed that preoperative CRP is an independent prognostic factor of OS and DFS respectively (HR=2.34 (1.26-4.31), P=0.006 and HR=1.83 (1.15-2.90), P=0.01). CONCLUSION: Preoperative inflammation measured by CRP is independently related with overall and disease-free survival of colorectal cancer.

Inflammatory markers for the early detection of post-operative infection: The same threshold for rectal and colic surgery?

INTRODUCTION: Anastomotic fistula is the most fearsome complication following colorectal surgery. Numerous studies have demonstrated the interest of postoperative CRP assay as an early diagnostic marker. Must the critical threshold for biological inflammatory markers remain the same, whether resection be colic or rectal? PATIENTS AND METHOD: This is a study based on a cohort constituted between 2011 and 2014, including 497 patients with planned colorectal resection. C-reactive protein and pro-calcitonin were measured daily from day before surgery to D4. All postoperative intra-abdominal complications were considered as an anastomotic fistula. Detection thresholds were calculated from the area under the ROC curve. RESULTS: An intra-abdominal septic complication occurred in 16.9% of the patients having undergone rectal resection vs. 9.9% of those having had colectomy (P=0.03). In the absence of complications there was no significant difference between the two groups in terms of postoperative inflammatory response as determined by either CRP or PCT assay. Following rectal resection, optimal area under the curve (AUC=0.87) corresponds to CRP on D4 for a threshold of 100mg/L: sensitivity 83.3%, NPV 95.3%. For colons with the same CRP at 100mg/L (AUC=0.71): sensitivity 63.6%, NPV 93.9%. CONCLUSION: Notwithstanding riskier surgery, the detection threshold for an anastomotic fistula following rectal surgery remains the same: CRP>100mg/L at D4.

Should CT scan be performed when CRP is elevated after colorectal surgery? Results from the inflammatory markers after colorectal surgery study.

INTRODUCTION: Serum concentration of C-reactive protein (CRP) that exceeds a pre-defined threshold between the 3rd and 5th postoperative day is a reliable marker of infectious complications after colorectal surgery. However, the optimal strategy to follow when a high CRP is found has not been defined. The aim of this study was to analyze the usefulness of computed tomography (CT) scan in this situation in a prospective cohort of patients following colorectal surgery. METHODS: Between November 2011 and April 2015, patients at two surgical centers who had undergone elective colorectal resection with anastomosis and who had a CRP>12.5mg/dL on the 4th postoperative day (POD) were prospectively included in a database. Data were collected concerning all complications occurring during the 30days following surgery, method of diagnosis, management and clinical course. The decision to perform a CT scan between POD 4 and POD 6 day was guided only by the elevation of CRP in the absence of any other clinical signs; results were analyzed to evaluate the diagnostic value of elevated CRP. Uni- and multivariable analyses were performed to identify risk factors for postoperative infection. RESULTS: The study included a total of 174 patients: 56 (32.1%) had a CT between POD 4 and 6, and this helped detect a postoperative complication in 55.4% of cases. Patients who did not undergo CT had lower CRP values (16.3 vs. 18.5, P=0.02). Among the 118 patients who did not undergo CT, 50.8% eventually developed an infectious complication. The sensitivity of CRP-guided CT was 76.7% with a negative predictive value of 78.8%. CONCLUSION: If an elevated CRP is found on POD 4, an abdominopelvic CT should be performed. A normal result does not formally eliminate the existence of intra-abdominal complication. A study protocol should be set up to evaluate whether systematic revisional surgery or repeat CT scan is the appropriate management if CRP in the next two days reveals persistent inflammation.

[Microdialysis monitoring of a free omentum flap]. / Surveillance par microdialyse d'un lambeau libre de grand épiploon.

INTRODUCTION: Microdialysis allows postoperative monitoring of free flaps. It allows determining their cellular metabolism in vivo by measuring glucose, lactate, and pyruvate. We report an application on a greater omentum free flap. CASE REPORT: A 77 year old female patient was operated for a vertex angiosarcoma. A large loss of vertex substance (175cm(2)) was rebuilt with a greater omentum free flap. Monitoring included hourly clinical observation (color, temperature, aspect), and flap surveillance using microdialysis CMA 60((R)) catheter. The first value was obtained 1h 30 after revascularization. The following recordings were made every hour for 48hours, then every 2hours for the next two days, then every 4hours. The following parameters were assessed: glucose (G), lactate (L), and pyruvate (P). The lactate/pyruvate (L/P) ratio was calculated after each dosage. Critical and alert values were the same as for other types of flaps. The first values for G, L, P, and L/P were respectively: 0.92mmol/l, 0.92mmol/l, 72micromol/l, and 13. The mean G, L, P, and L/P values were respectively: 5.9mmol/l, 6mmol/l, 269micromol/l, and 22. The values corresponding to a stable metabolism were obtained on the first postoperative day with the following mean G, L, P, and L/P values of: 5.9mmol/l, 5.3mmol/l, 256micromol/l, and 21. Surgical evolution was uneventful. DISCUSSION: In cervicofacial reconstruction, the greater omentum free flap is often associated to a gastric strip (gastroepiploic flap) and either greatly or completely covered. It is thus little accessible to postoperative clinical surveillance and ischemic complications may be overlooked and compromise the flap's survival. Complementary surveillance techniques such as microdialysis are necessary.