Between May 1998 and December 2012, 55 patients underwent pancreatectomy for SPT of the pancreas at Sir Run Run Shaw Hospital, Hangzhou, China. We retrieved 29 patients who underwent distal pancreatectomy. One patient with liver metastasis and colon cancer was excluded from the study, and 28 patients were included in this study. The medical records of all patients were retrospectively reviewed, including demographics, clinical presentation, operative results, hospital course, morbidity and mortality, pathological findings, and long-term follow-up data. The Institutional Review Board of Sir Run Run Shaw Hospital of Zhejiang University approved this study protocol.

All operations were performed by four experienced surgeons using our institution’s standardized technique. Laparoscopic pancreatic surgery was adopted in 2003 at our institution, therefore, all of the patients who underwent surgery from 1998 to 2003 were included in the open surgery group. After 2003, the surgeons could decide whether to perform laparoscopic or open surgery with the informed consent of the patients.

The operative procedure for LDP has been described previously[11,12]. Briefly, the patient was placed in supine position with the head slightly elevated. The surgeon and the second assistant who held the laparoscope stood on the right side of the patient and the first assistant stood on the left. One initial 10-mm trocar was placed for laparoscopy below the umbilicus. A 30-degree telescope was inserted to examine the peritoneal cavity to rule out metastatic disease. After general examination, the other four trocars (one 12 mm, three 5 mm) were inserted into the left upper flank, left flank, right upper flank, and right flank quadrants; and the five trocars were arranged in a V shape. Under pneumoperitoneum, the gastrocolic ligament was divided for entrance to the lesser sac using a harmonic scalpel (Harmonic Ace; Ethicon Endo-Surgery, Cincinnati, OH, United States). The mobilization of the pancreas began at the superior border until the proximal splenic artery was visualized. The pancreas was mobilized at the inferior border to visualize the superior mesenteric and splenic veins. After creating a tunnel behind the neck of the pancreas, the pancreas was transected with an endoscopic linear stapler (Endocutter 60 stapler, white or blue cartridge; Ethicon Endo-Surgery, Cincinnati, OH, United States). For spleen-preserving procedures, the distal pancreas was freely dissected from the splenic vessels by ligation of the small branches connected to the pancreas using small titanium vascular clips or a harmonic scalpel. In the case of DP with splenectomy, the splenic artery and splenic vein were divided. The spleen was resected with the pancreas.

ODP was performed in the same manner as LDP through an upper midline incision. However, a variety of techniques, including suturing and/or stapling, were used to control the pancreas stump, according to the preference of the individual surgeon.

Diet was started after the first flatus had been passed. Patients were discharged if they considered themselves sufficiently recovered; tolerated food without any significant discomfort; and had no major complications. Postoperative pancreatic fistula was defined as any measurable volume of drainage fluid (amylase > 3 times the upper limit of normal serum value) on or after postoperative day 3[13]. Three different grades of postoperative pancreatic fistula (A-C) were defined according to the clinical impact on the patient’s hospital course[13]. Postoperative mortality was defined as death occurring within 30 d after surgery.

Patients were followed up as outpatients by telephone. We included data up to the last follow-up in March 2013. Recurrence or distant metastasis was diagnosed pathologically by surgical resection, biopsy, or cytology and/or radiological examination. The fasting blood glucose level (normal ≤ 110 mg/dL) was used to evaluate pancreatic endocrine function. The clinical evaluation was used to assess the pancreatic exocrine function. Patients with diarrhea, weight loss, and fatty stools were considered to have pancreatic exocrine insufficiency.

Continuous clinicopathological data were expressed as median (range) or mean ± SD as appropriate. Categorical variables were reported as number and percentage. Continuous clinicopathological data were analyzed with Student’s t test (or Mann-Whitney U test). Categorical variables were analyzed with the χ² test (or Fisher’s exact test). All statistical analyses were performed using SPSS version 16.0. P < 0.05 was considered statistically significant.

Table 1 summarizes the baseline characteristics of the LDP and ODP groups. Fifteen patients underwent LDP and 13 ODP. The two groups were balanced in terms of their baseline characteristics: age, body mass index (BMI), symptoms, comorbidity, American Society of Anesthesiologists (ASA) score, tumor size, spleen preservation rate, and combined resection rate, except for a significant female predominance in the LDP group: 100% women (n = 15) compared with 69.2% (n = 9) in the ODP group (P = 0.035).

Table 2 summarizes the operative outcomes and hospital courses of the LDP and ODP groups. There were no significant differences in the operating time (171 min vs 178 min, P = 0.755) between the two groups. LDP produced a significantly lower amount of intraoperative blood loss (149 mL vs 580 mL, P = 0.002), lower transfusion requirement (6.7% vs 46.2%, P = 0.029), shorter first flatus time (1.9 d vs 3.5 d, P = 0.000), shorter diet start time (2.3 d vs 4.9 d, P = 0.000), and shorter postoperative hospital stay (8.1 d vs 12.8 d, P = 0.029) than ODP.

There were no significant differences in postoperative complication rates (33.3% vs 38.5%, P = 1.000), pancreatic fistula rates (26.7% vs 30.8%, P = 0.972), and reoperation rates (0.0% vs 7.7%, P = 0.464) between the two groups. One patient underwent laparotomy for acute peritonitis after open spleen-preserving DP. We found biliary and pancreatic fistulas from the pancreatic stump. A calculus (diameter 6 mm) was incarcerated in the distal common bile duct, which led to bile regurgitation through the pancreaticobiliary common channel. The procedure consisted of cholecystectomy, common bile duct exploration, T tube drainage, and suture of the pancreatic remnant. The patient was discharged 24 d after the second operation. No perioperative mortality was recorded.

Table 3 shows the pathological characteristics of the two groups. All patients had negative surgical margins at final pathology. An average number of 5.3 lymph nodes were resected without metastases. There was no significant difference in the number of harvested lymph nodes (4.6 vs 6.4, P = 0.549) between the two groups. In seven (25%) patients, the pathological findings were consistent with malignant features of SPT[14]. The malignant features included local invasion of peripancreatic tissue (n = 6), perineural invasion (n = 2), no liver metastasis, invasion of adjacent organs and angioinvasion. There were no significant differences in the pathological characteristics between the two groups.

The median follow-up was 33 (3-100) mo for the LDP group and 45 (17-127) mo for the ODP group. All patients were alive with one recurrence. A 57-year-old female patient underwent ODP, and the pathology report revealed SPT with peripancreatic tissue invasion and perineural invasion. Six years after surgery, she developed peritoneal recurrence, which was treated by open tumorectomy and traditional Chinese medicine. At a follow-up of 15 mo after the second operation, no tumor recurrence was found. After surgery, six patients developed pancreatic exocrine or endocrine insufficiency; two received pancreatic enzyme therapy; and one developed diabetes and received insulin therapy. There were three cases of hyperglycemia with diet control.

Solid pseudopapillary tumor (SPT) of the pancreas is a rare neoplasm. Some patients have benefited from laparoscopic pancreatectomy. Laparoscopic distal pancreatectomy (LDP) has not previously been compared with open distal pancreatectomy (ODP) for SPT.

Recently, several case reports and small series have shown less intraoperative blood loss and rapid recovery after LDP for SPT. However, the short-term and long-term outcomes of LDP compared with ODP for SPT required further assessment.

In the present study, the authors compared the short-term and long-term outcomes of LDP and ODP for SPT, and showed that LDP was suitable and minimally invasive for treating SPT and could achieve similar oncological outcomes (harvested lymph nodes and margin status) and long-term outcomes as ODP.

This study showed that LDP for SPT had the advantages of minimally invasive surgery, less intraoperative blood loss, and rapid recovery. The mortality, morbidity, oncologic outcomes and long-term results of LDP were similar to those of ODP. These findings are helpful in decision-making for the treatment of SPT of the distal pancreas.

The topic is interesting, and despite the rarity of SPT, the study includes a large series of patients.