214 patients underwent pancreatic resection during the study period of which 35 patients underwent TP and 179 patients underwent PD. Patients who underwent distal pancreatectomy were excluded from the study. The most common indication for TP was IPMN in 57.1% of the cases followed by pancreatic adenocarcinoma in 34.3%. Table 1 depicts the indications for pancreatic resection in the two groups. It seems that PD is the operation of choice in patients with malignant diseases (38.2% vs. 76%, p<0.001), while TP is preferred in benign diseases such as IPMN (57.1% vs. 19.5%, p<0.001).
The two groups were homogenous in terms of demographics and clinical presentation with no age or gender preferences for each procedure. Clinically jaundice was more prevalent in the PD group (48.9% vs. 26.5%, p-0.02). Preexisting diabetes mellitus (DM) was more prevalent in the TP group (62.9% vs. 37.4%, p-0.005) and smoking was more prevalent in the PD group (9.7% vs. 39.4%, p-0.001) (Table 2). Operative time was significantly longer for the TP group (238.7±41.9 vs. 221.3±40.1, p-0.02). Sixteen patients (8.9%) of the PD group needed blood transfusion compared to none of the TP group. This did not reach statistical significance but showed a trend towards favoring the TP (p-0.08).
The primary measure of outcome was perioperative mortality, this was not different between TP and PD and stands on 2.9% and 5% respectively (p-0.58) (Table 3). Median overall procedure survival was not different between the two groups (67.7 vs. 67.5 months, Log rank 0.95) as depicted by the Kaplan Meier curve in Figure 1.
Secondary measure of outcome was short-term morbidity; we observed that overall complication rate was significantly lower in the TP group (17.1% vs. 55%, p<0.001) and the rate of major complications (Dindo-Clavien >3) in the TP group was lower but did not reach statistical significance (2.9% vs. 11.2%, p-0.13). Other outcomes such as length of stay in the hospital (LOS), need for admission in the intensive care unit and type of discharge did not differ between the two groups as depicted in table 3.
Table 4 depicts the rate of the specific complications in both study and control group; we can observe that complications such as surgical site infection (p<0.001), peritoneal abscess (p-0.03), bile leak (p-0.002) and cardiovascular complications (p-0.03) were all significantly more prevalent in the PD group. This might be attributed to the 29% pancreatic leaks present in this group and the impact it might have on patient’s morbidity.
Oncologically, median number of lymph nodes harvested was significantly higher in the TP group 20 (14-25) vs. 15 (11-19) (p-0.003). In patients with malignant disease positive resection margins (R1) was observed in 3.4% (n-6) of the patients in the PD group and in 2.9% (n-1) of the TP group (p-0.88).
Median overall survival of the pancreatic adenocarcinoma patients was significantly higher for the TP group (21.6 vs. 10 months, log rank 0.006) as depicted by the Kaplan Meier Curve in Figure 2.
On Univariate analysis variables significantly associated with perioperative mortality included age (75.4±5.9 vs. 67.7±12.1, p-0.04), malignancy (40% vs. 70.6%, p-0.04) and major postoperative complications (Dindo-Clavien >3) (90% vs. 5.9%, p<0.001). Multivariate analysis showed that malignancy (p<0.001) and major complications (p<0.001) are independent predictors of perioperative mortality in this cohort of patients.
On Univariate and multivariate analysis age was the only independent predictor of major complications among all other variables.
Interestingly enough TP is negatively associated with perioperative mortality and postoperative major complications, with a protecting effect from major complications (OR 0.25 (CI95% 0.01-1.47)).
Table 5 summarizes the descriptive data and the perioperative outcome of the major studies comparing TP and PD.