We have read with interest the article by Uzunoglu et al^[1] entitled “Preoperative pancreatic resection (PREPARE) score: a prospective multicenter-based morbidity risk score” for prediction of postoperative morbidity and mortality related to pancreatic resection. Pancreatic resections are generally considered as difficult operations due to the high risk of perioperative morbidity.^[2] The existing preoperative risk grading systems do not provide an optimal risk stratification. We have validated the PREPARE score in Turkish patients in the past years.

 

Between 2010 and 2015, 122 patients who underwent pancreatic resection due to disease of pancreatic origin or not and had no positive resection margins on final pathology report were included for the evaluation. Postoperative complications were determined according to the Clavien-Dindo classification,^[3] and complications graded as III to V were defined as major. The PREPARE score was calculated using eight certain parameters (Table 1). The patients were divided into the low-risk (<6 points), intermediate-risk (6-9 points), and high-risk (>9 points) groups.

 

Model discrimination was measured by the area under the receiver-operating characteristic (ROC) curve (AUC). Calibration was assessed using the Hosmer-Lemeshow goodness-of-fit test and the corresponding calibration curves. Statistical evaluation has been performed by using the STATA 8.0 statistical package (StataCorp, LP).

 

The main characteristics and the PREPARE parameters of the patients are presented in Table 1. There was no major complication in the low-risk group; however, 68.6% and 31.4% of the major complications occurred in the high-risk group and intermediate-risk group (Table 2). The ROC curve showing the discriminative power of the PREPARE score was found to be 0.541, while the calibration was 3.352 in Hosmer-Lemeshow Chi² test with a P value of 0.764. Within the validation cohort, approximately 70% of all patients were classified as either low-risk or high-risk groups with an accuracy rate of 70%.

 

The preoperative risk scoring systems can be classified into two groups. The first group includes grading systems such as the ASA score, acute physiology and chronic health evaluation (APACHE-II) score, and physiological and operative severity scoring system for enumeration of morbidity and mortality (POSSUM) score, indicating an overall operative risk in various specialities. The second group is specialized to pancreatic surgery, and includes scoring systems such as readmission after pancreatectomy (RAP) score, PREPARE score, and Braga score.^{[1, 4, 5]} Simple and easily accessible variables and taking into account the patients’ cardiovascular and nutritional status seem to be the most important advantages of the PREPARE score. However, several anatomical features such as pancreatic texture and duct diameter are of great importance for the surgical outcomes of pancreatic resections.^[6] Although these parameters can only be assessed intraoperatively and thus cannot provide any preoperative decision making, we suggest that a risk stratification without these parameters cannot completely reflect the accurate prediction of postoperative complications. The experience of the center and type of operative technique also have significant impact on outcomes. The authors reproted that the PREPARE score reached an accuracy of 75% for correctly predicting occurrence or nonoccurrence of major surgical complications in 80% of all analyzed patients within the validation cohort. We also obtained an accuracy rate of 70%, and for our opinion, these accuracy rates are not enough to show the success and reliability of this scoring system.

 

Despite these limitations, the PREPARE score seems to be the most simple and useful scoring system among all grading methods, and can be easily used in routine practice for risk stratification for patients undergoing pancreatic resections.

 

 

Hüseyin Celik, Murat Ozgur Kilic, Ahmet Erdogan,

Cengiz Ceylan and Mesut Tez

 

 

1 Uzunoglu FG, Reeh M, Vettorazzi E, Ruschke T, Hannah P, Nentwich MF, et al. Preoperative pancreatic resection (PREPARE) score: a prospective multicenter-based morbidity risk score. Ann Surg 2014;260:857-864. PMID: 25243549

2 Büchler MW, Wagner M, Schmied BM, Uhl W, Friess H, Z’graggen K. Changes in morbidity after pancreatic resection: toward the end of completion pancreatectomy. Arch Surg 2003;138:1310-1315. PMID: 14662530

3 Clavien PA, Barkun J, de Oliveira ML, Vauthey JN, Dindo D, Schulick RD, et al. The Clavien-Dindo classification of surgical complications: five-year experience. Ann Surg 2009;250:187-196. PMID: 19638912

4 Valero V 3rd, Grimm JC, Kilic A, Lewis RL, Tosoian JJ, He J, et al. A novel risk scoring system reliably predicts readmission after pancreatectomy. J Am Coll Surg 2015;220:701-713. PMID: 25797757

5 Braga M, Capretti G, Pecorelli N, Balzano G, Doglioni C, Ariotti R, et al. A prognostic score to predict major complications after pancreaticoduodenectomy. Ann Surg 2011;254:702-708. PMID: 22042466

6 Casadei R, Ricci C, Taffurelli G, D’Ambra M, Pacilio CA, Ingaldi C, et al. Are there preoperative factors related to a “soft pancreas” and are they predictive of pancreatic fistulas after pancreatic resection? Surg Today 2015;45:708-714. PMID: 25331230

 

(doi: 10.1016/S1499-3872(16)60055-3)

Published online January 7, 2016.

 

 

We read with interest the article “External validation of PREPARE score in Turkish patients who underwent pancreatic surgery” that analyzes the PREPARE score published in Annals of Surgery in 2014.^[1] One hundred and twenty-two Turkish patients who underwent pancreatic surgery were analyzed postoperatively by the PREPARE score. An accuracy of 70% of the score was found. The authors concluded that despite limitations, the PREPARE score seems to be the most simple and useful scoring system among all grading methods. We absolutely agree to the conclusion of the authors. The PREPARE score only includes simple preoperatively available diagnostic parameters which enables sufficient risk stratification.^[1] The authors suggested that risk stratification of patients undergoing pancreatic surgery can not enable accurate risk prediction without adding intraoperative parameters like pancreatic texture or pancreatic duct diameter. In this point we have our own opinions. Several pancreas specific risk scores including intraoperative parameters like texture of the parenchyma have been published.^[2-5] In most of them, high accuracy and sufficient risk prediction were reported. But this postoperative risk stratification does not enable a preoperative optimization of the patient’s health status. Any scoring system should offer the possibility of improvement in clinical practice. The PREPARE score highlights options for management before surgery. In reality, postoperative risk stratification without preoperative evaluations is of less clinical importance. This may be one of the reasons why most of the published scores have not been validated by other centres of pancreatic surgery so far. On the other hand, we have to mention that the PREPARE score mandates further verification and possible future modification of the selection and weighting of variables.

 

In summary, the article “External validation of PREPARE score in Turkish patients who underwent pancreatic surgery” confirms the accuracy and sufficient risk stratification of the PREPARE score. Furthermore, it demonstrates that external validations of the PREPARE score by other pancreatic centers are urgently needed.

 

 

Matthias Reeh and Faik G Uzunoglu

 

 

1 Uzunoglu FG, Reeh M, Vettorazzi E, Ruschke T, Hannah P, Nentwich MF, et al. Preoperative pancreatic resection (PREPARE) score: a prospective multicenter-based morbidity risk score. Ann Surg 2014;260:857-864. PMID: 25243549

2 Braga M, Capretti G, Pecorelli N, Balzano G, Doglioni C, Ariotti R, et al. A prognostic score to predict major complications after pancreaticoduodenectomy. Ann Surg 2011;254:702-708. PMID: 22042466

3 Greenblatt DY, Kelly KJ, Rajamanickam V, Wan Y, Hanson T, Rettammel R, et al. Preoperative factors predict perioperative morbidity and mortality after pancreaticoduodenectomy. Ann Surg Oncol 2011;18:2126-2135. PMID: 21336514

4 Brooks MJ, Sutton R, Sarin S. Comparison of surgical risk score, POSSUM and p-POSSUM in higher-risk surgical patients. Br J Surg 2005;92:1288-1292. PMID: 15981213

5 Knight BC, Kausar A, Manu M, Ammori BA, Sherlock DJ, O’Reilly DA. Evaluation of surgical outcome scores according to ISGPS definitions in patients undergoing pancreatic resection. Dig Surg 2010;27:367-374. PMID: 20938180

 

(doi: 10.1016/S1499-3872(16)60056-5)

Published online January 7, 2016.