Yu-Meng Tan

Critical Appraisal of 232 Consecutive Distal Pancreatectomies With Emphasis on Risk Factors, Outcome, and Management of the Postoperative Pancreatic Fistula : A 21-Year Experience at a Single Institution

OBJECTIVE To critically analyze a large single-institution experience with distal pancreatectomy (DP), with particular attention to the risk factors, outcome, and management of the postoperative pancreatic fistula (PF). DESIGN Retrospective study. SETTING Tertiary referral center. PATIENTS A total of 232 consecutive patients with pancreatic or extrapancreatic disease necessitating DP over 21 years. INTERVENTIONS Twenty-one patients underwent spleen-preserving DP, 117 underwent DP with splenectomy, and 94 underwent DP with multiorgan resection. MAIN OUTCOME MEASURES The perioperative and postoperative data of patients who underwent DP were analyzed. This included factors associated with postoperative morbidity with particular attention to the PF (defined by the International Study Group of Pancreatic Fistula) and changing trends in operative and perioperative data during the study period. RESULTS The overall operative morbidity and mortality were 47% (107 patients) and 3% (7 patients), respectively. During the study period, the rates of resection increased from 3 cases to 23 per year, and increasingly these were performed for smaller and incidental lesions. The morbidity rate remained unchanged, but there was a decline in postoperative stay and the need for care in the intensive care unit. Pancreatic fistulas occurred in 72 patients (31%); 41 (18%) were grade A, 13 (6%) grade B, and 18 (8%) grade C. Increased weight, higher American Society of Anesthesiologists score, blood loss greater than 1 L, increased operation time, decreased albumin level, and sutured closure of the stump without main duct ligation were associated with a postoperative PF on univariate analysis. A DP with splenectomy was associated with a higher incidence of grade B or C PF and non-PF-related complications. Ninety-two percent of PFs were successfully managed nonoperatively. Clinical outcomes correlated well with PF grading, as evidenced by the progressive increase in outcome measures such as postoperative stay, readmissions, reoperations, radiologic interventions, and non-PF-related complications from grade A to C PFs. CONCLUSIONS Pancreatic fistula is the most common complication after DP and its incidence varies depending on the definition applied. Several risk factors for developing a PF were identified. Splenic preservation after DP is safe. The grade of a PF correlates well with clinical outcomes, and most PFs may be managed nonoperatively.

A review of mucinous cystic neoplasms of the pancreas defined by ovarian-type stroma: clinicopathological features of 344 patients.

Despite formal definitions of mucinous cystic neoplasms (MCNs) and intraductal papillary neoplasms (IPMNs) by the World Health Organization (WHO) and Armed Forces Institute of Pathology (AFIP), several controversies with regard to MCNs remain. The aim of this review was to determine the clinicopathological features of MCNs defined by ovarian-type stroma (OS) as proposed by the WHO and AFIP and to compare them with MCNs defined by less stringent criteria. A MEDLINE search was conducted to identify English-language articles on pancreatic MCNs from 1996 to 2005. Twenty-five studies were identified. The studies were divided into 2 groups: group A included 10 studies with 344 patients whereby the presence of OS was a criteria for the diagnosis of MCNs, and group B, included 15 studies comprising 761 patients whereby the presence of OS was not mandatory for the diagnosis of MCNs. Patients in group A (MCNs as defined by OS) were almost always female (99.7%), with a mean age of 47 (range, 18–95) years. MCNs were located predominantly in the body or tail of the pancreas (94.6%) and had a mean size of 8.7 cm (range, 0.6–35 cm); 76% were symptomatic, 6.8% demonstrated ductal communication, and 27% were malignant. At a mean follow-up of 57.5 (range, 1–264) months and 43 (range, 2–257) months after surgery, 97.9% of benign and 61.9% of malignant neoplasms were disease free, respectively. Patients in group B were older and had a higher proportion of males. Neoplasms were more evenly distributed in the pancreas, were smaller, communicated more frequently with the pancreatic duct, and were composed of a higher proportion of malignant tumors compared with group A. Their clinicopathological features were intermediate between those of group A and patients with IPMN. Pancreatic MCNs with OS have unique and distinct clinicopathological features. MCNs should be defined by the presence of OS, as it is the most reliable way of distinguishing MCNs from IPMN. Adoption of “looser” criteria will result in misclassification of some IPMNs as MCNs.

CT in the Preoperative Diagnosis of Fish Bone Perforation of the Gastrointestinal Tract

OBJECTIVE Foreign body perforation of the gastrointestinal (GI) tract has diverse clinical manifestations, and the correct preoperative diagnosis is seldom made. We report our experience with the use of CT in the preoperative diagnosis of fish bone perforation of the GI tract in seven patients. To our knowledge, this series is the largest to date addressing the role of CT in the diagnosis of fish bone perforation. CONCLUSION Clinical presentation and radiography are unreliable in the preoperative diagnosis of fish bone perforation of the GI tract. This limitation can be overcome with the use of CT, which is accurate in showing the offending fish bone. The accuracy of CT is limited by observer dependence. A high index of suspicion should always be maintained for the correct diagnosis to be made.

An Appraisal of Surgical and Percutaneous Drainage for Pyogenic Liver Abscesses Larger Than 5 cm

Objective:To determine whether first-line treatment with percutaneous or surgical drainage of liver abscesses larger than 5 cm results in better clinical outcome. Summary Background Data:Pyogenic liver abscesses larger than 5 cm are currently treated by intravenous antibiotics and either percutaneous (PD) or surgical drainage (SD). Percutaneous techniques have been increasingly performed in place of open drainage as first-line treatment. This paradigm shift has been fueled by the drive for low-risk and less-invasive procedures and the surgical option being reserved for percutaneous failures. Yet there is a lack of data to support percutaneous drainage over open surgical drainage as first-line treatment. Methods:Over a 3-year period, 80 patients with liver abscesses larger than 5 cm amenable to PD and SD were included in the study. This situation was possible as 1 team of surgeons favored the use of PD and 1 team favored the use of SD as first-line treatment. The treatment outcomes in both groups were compared, and clinical end-points included time to defervescence of fever, failure of treatment, secondary procedures, hospital stay, morbidity, and mortality. Results:PD was performed in 36 patients and SD in 44 patients as first-line treatment. Clinical, laboratory, and abscess parameters were comparable in both groups. Sixty-four of 80 patients (80%) had multiloculated abscess. The time to defervescence of fever was not statistically significant (PD versus SD, 4.85 versus 4.38 days; P = 0.09). However, SD had less treatment failures (3 versus 10, P = 0.013), less requirement for secondary procedures (5 versus 13, P = 0.01), and shorter length of hospital stay (8 versus 11 days, P = 0.03). There was no difference in morbidity or mortality rates. Conclusions:The results of our study show that for large liver abscesses more than 5 cm, SD provides better clinical outcomes than PD in terms of treatment success, number of secondary procedures, and hospital stay with comparable morbidity and mortality rates. SD should be considered as first-line treatment of large liver abscesses.

Pancreatic Serous Oligocystic Adenomas: Clinicopathologic Features and a Comparison with Serous Microcystic Adenomas and Mucinous Cystic Neoplasms

The preoperative distinction between serous cystic neoplasms (SCNs) and mucinous cystic neoplasms (MCNs) is essential, as all MCNs are considered malignant or potentially malignant and should be surgically resected, whereas SCNs are almost always benign. However, the radiologic distinction between SCNs and MCNs is frequently difficult especially with serous oligocystic adenoma (SOA), a morphologic variant of SCN, as both SOA and MCN appear on cross-sectional imaging as a solitary macrocystic lesion in the pancreas. We reviewed all SOAs managed at our institution to determine if any clinicopathologic features would prove useful for establishing a preoperative diagnosis. Over a 15-year period, 64 patients with a pathologically confirmed diagnosis of a pancreatic cystadenoma or cystadenocarcinoma treated at Singapore General Hospital were retrospectively reviewed. There were 27 MCNs and 37 SCNs including 12 SOAs. In addition, 40 cases of SOA previously reported in the literature were reviewed and analyzed together with the 12 patients, making this a series of 52 SOAs. In our experience, SOAs comprised 32.4% of the SCNs, and females predominated (7/12). The median age of the patients was 42.5 years (range 22–74 years), and only 4 of the 12 patients were symptomatic. Most of the cysts were located in the body or tail of the pancreas (9/12), and the median cyst size was 52.5 mm (range 10–190 mm). When the clinicopathologic features of SOAs and serous microcystic adenomas (SMAs) were compared, there was no difference between the patients with SOAs and SMAs in terms of age, sex, presence of symptoms, cyst size, or site of the lesion. However, SOAs occurred in the women less frequently (67.3% vs. 96.3%, P = 0.004), were smaller [40 mm (range 10–190 mm) vs. 95 mm (range 25–180 mm), P < 0.001], and occurred more commonly in the head of the pancreas [25 (48.1%) vs. 2(7.4%)] compared to MCNs. None of the SOAs were frankly malignant compared to the 29.6% of MCNs that were. SOAs and SMAs have similar clinicopathologic features. On the other hand, SOAs differ from MCNs by their relatively higher male/female ratio, higher frequency of tumors occurring in the head of the pancreas, and smaller cyst size. Knowledge of these distinguishing clinical features when used in combination with other diagnostic modalities such as endoscopic ultrasonography/fine-needle aspiration will enable clinicians to better differentiate these two pathologic entities preoperatively.

Intra-abdominal and Retroperitoneal Lymphangiomas in Pediatric and Adult Patients

Intra-abdominal and retroperitoneal lymphangiomas are a rare, congenital malformations of the lymphatics, which are found predominantly in children. The aim of this study is to evaluate the clinical features of this tumor, highlighting the differences in adults and pediatric patients. We also evaluate the preoperative diagnosis, radiological features, surgical treatment, and outcome of this rare condition. Between 1990 and 2004, 14 patients who underwent surgical resection of an intra-abdominal lymphangioma were reviewed retrospectively. There were five pediatric patients between fetal age and 17 years of age and nine adults between 31 and 62 years of age. Overall, females outnumbered males in the series, with a male-to-female ratio of 3:4. However, males predominated in the pediatric age group with a male-to-female ratio of 1.5:1. The clinical presentation of children was more acute ranging from 3 days to 2 months. In adults, four patients were asymptomatic, and the remaining five had symptom duration ranging from 2 weeks to a year. The lymphangiomas occurred in the mesentery (n = 4), retroperitoneum (n = 4), omentum (n = 3), pancreas (n = 2), and spleen (n = 1). All the patients underwent total surgical resection with or without organ resection, and there were no recurrences at a median follow-up of 2 years (range; 3 months–13 years). This series demonstrates that abdominal lymphangiomas have a male preponderance and present more acutely in pediatric patients, whereas in adults, female patients predominate and the history is more chronic.

Clinicopathological features of patients with concomitant intraductal papillary mucinous neoplasm of the pancreas and pancreatic endocrine neoplasm.

Background/Aims: The occurrence of concomitant pancreatic endocrine neoplasm (PEN) and intraductal papillary neoplasm (IPMN) of the pancreas has rarely been reported. We describe our experience with 3 patients with this association and review the existing literature. Methods: From 1990 to 2005, 65 patients who underwent surgery for a PEN or IPMN were retrospectively reviewed. Forty-three patients had a PEN, 19 had an IPMN and 3 had both an IPMN and PEN. The 3 patients with concomitant IPMN and PEN are the focus of the current study and their clinicopathological features are reported together with 7 patients previously reported in the literature. Results: There were 10 patients with a median age of 62 years (range 40–73). The male:female ratio was equal. Seven of 10 patients were symptomatic and the most common symptoms were abdominal pain (n = 5), jaundice (n = 2) and loss of weight (n = 2). The median size of the endocrine neoplasms was 14 mm (range 2–30) and they occurred in the head (n = 3), body (n = 2) and tail (n = 5). Seven of the PENs were classified as benign, 2 were potentially malignant, and 1 was frankly malignant with lymph node involvement. None of the endocrine neoplasms were functioning. The IPMNs were found in the tail (n = 4), head (n = 3), head and body (n = 1), body (n = 1) and the entire pancreas (n = 1). Five of these neoplasms were benign, 2 were borderline and 3 were malignant (1 carcinoma in situ). Conclusion: The occurrence of concomitant IPMN and PEN is more frequent than would be expected. However, it is difficult in the present analysis to determine if this association is more than just fortuitous.

Ocular Manifestations and Complications of Pyogenic Liver Abscess

In anecdotal reports, septic metastatic lesions from a pyogenic liver abscess can result in endogenous endophthalmitis, an infection of intraocular contents. Recent reports suggest that this devastating complication is increasing in frequency. The initial presentation may be nonspecific and easily misdiagnosed by the surgical team. When the infecting organism is virulent, it tends to be rapidly progressive and often leads to permanent visual deterioration or blindness despite medical intervention. We conducted a study to determine the incidence of endophthalmitis associated with pyogenic liver abscess, to identify its associations, and to determine the outcome of treatment. A retrospective review of 289 patients with a clinical diagnosis of pyogenic liver abscess admitted between January 1995 and March 2001 revealed 10 patients (3.5%) with the complication of endogenous endophthalmitis. Among them, seven had a previous history of diabetes mellitus. The offending organism was Klebsiella pneumoniae in all cases. There was no mortality in this series. Final visual outcomes of our patients were as follows: Five had no light perception (two had undergone evisceration), one had light perception only, and four were able to visualize hand motion only. There is a trend toward a worse outcome when ocular symptoms are not diagnosed and treated within 24 hours of onset. Of the five patients who lost their eyesight completely, three were initially misdiagnosed, and referral to the ophthalmologist was delayed. Surgeons must be alert to the complication of endogenous endophthalmitis. Ocular symptoms in patients treated for pyogenic liver abscess must be referred early for an ophthalmologic consult. Increased awareness and a high index of suspicion are required for salvage of visual function.

FACTORS AFFECTING EARLY MORTALITY IN SPONTANEOUS RUPTURE OF HEPATOCELLULAR CARCINOMA

Background:  Spontaneous rupture of hepatocellular carcinoma (HCC) is a catastrophic surgical emergency with high mortality rates. The aim of this study is to determine the factors associated with the prognosis and to assess the outcome of different management strategies.

Non-neoplastic cystic and cystic-like lesions of the pancreas : May mimic pancreatic cystic neoplasms

Background:  Cystic lesions of the pancreas consist of a broad range of pathological entities. With the exception of the pancreatic pseudocyst, these are usually caused by pancreatic cystic neoplasms. Non‐neoplastic pancreatic cystic and cystic‐like lesions are extremely rare. In the present article, the surgical experience with these unusual entities over a 14‐year period is reported.