Defining the Role of Surgery for Primary Gastrointestinal Tract Melanoma

Objective The objective of the study was to determine the outcomes for primary gastrointestinal melanomas (PGIM). Material and methods The Surveillance, Epidemiology, and End Results database (1973–2004) was queried. Results Overall, 659 cases of PGIM were identified. The annual incidence of PGIM was approximately 0.47 cases per million in 2000. Overall median survival time was 17 months. Tumors were identified in the oral–nasopharynx (32.8%), anal canal (31.4%), rectum (22.2%), esophagus (5.9%), stomach (2.7%), small bowel (2.3%), gallbladder (1.4%), and large bowel (0.9%). Univariate analysis demonstrated age, tumor location, stage, surgery, and lymph node status were significant predictors of improved survival. MST has not been reached for tumors located in the large bowel, while tumors located in the stomach demonstrated the shortest median survival (5 months). Improvement in MST was observed for those patients undergoing surgical resection. The presence of lymph node involvement conferred a poorer prognosis. Multivariate analysis of the cohort identified that location, advanced tumor stage, failure to undertake surgical resection, positive lymph node status, and age were all independent predictors of poorer outcome. Conclusion PGIM occurs most often in the oral–nasopharynx and anal canal. Surgical extirpation is the only identifiable treatment modality that significantly improves survival.     

Urokinase mediates fibrinolysis in the pulmonary microvasculature

The role of urokinase-type plasminogen activator (uPA) and its receptor (uPAR) in fibrinolysis remains unsettled. The contribution of uPA may depend on the vascular location, the physical properties of the clot, and its impact on tissue function. To study the contribution of urokinase within the pulmonary microvasculature, a model of pulmonary microembolism in the mouse was developed. Iodine 125 ((125)I)-labeled fibrin microparticles injected intravenously through the tail vein lodged preferentially in the lung, distributing homogeneously throughout the lobes. Clearance of (125)I-microemboli in wild type mice was rapid and essentially complete by 5 hours. In contrast, uPA(-/-) and tissue-type plasminogen activator tPA(-/-) mice, but not uPAR(-/-) mice, showed a marked impairment in pulmonary fibrinolysis throughout the experimental period. The phenotype in the uPA(-/-) mouse was rescued completely by infusion of single chain uPA (scuPA). The increment in clot lysis was 4-fold greater in uPA(-/-) mice infused with the same concentration of scuPA complexed with soluble recombinant uPAR. These data indicate that uPA contributes to endogenous fibrinolysis in the pulmonary vasculature to the same extent as tPA in this model system. Binding of scuPA to its receptor promotes fibrinolytic activity in vivo as well as in vitro. The physical properties of fibrin clots, including size, age, and cellular composition, as well as heterogeneity in endothelial cell function, may modify the participation of uPA in endogenous fibrinolysis. (Blood. 2000;96:1820-1826)     

Defining Treatment and Outcomes of Hepaticojejunostomy Failure Following Pancreaticoduodenectomy

Background

The overall complication rate after pancreaticoduodenectomy (PD) approaches 50 %, with anastomotic failure being the most frequent cause of serious postoperative morbidity. Hepaticojejunostomy leaks (also called bile leaks) are the second most common type of leak, behind pancreaticojejunostomy leaks, yet have been the focus of only a single study as reported by Suzuki et al. (Hepatogastroenterology 50:254–257, 12).

Methods

We reviewed the recent experience with bile leaks at a single, high-volume pancreatic surgery center over a six-year time period.

Results

Bile leaks were identified in 16 out of 715 patients (2.2 %). Low preoperative albumin was associated with an increased risk. Bile leaks typically manifested within the first week after surgery as bilious drainage in a surgically placed drain. Associated warning signs included fever and leukocytosis. Patients with a bile leak frequently developed other complications, including a pancreatic fistula, wound infection, delayed gastric emptying, and sepsis. The impact on perioperative outcomes was comparable to patients with a pancreatic leak. A grading system is proposed based on the International Study Group on Pancreatic Fistula model. Grade A bile leaks were classified as those managed with prolonged drainage by operatively placed drains, grade B bile leaks with percutaneous abdominal drainage, and grade C bile leaks with insertion of a percutaneous transhepatic biliary drainage.

Conclusions

Hepaticojejunostomy leaks are rare after PD. The complication severity ranges from trivial to life threatening and is comparable overall to pancreaticojejunostomy leaks. Surgical intervention is rarely, if ever, required. With prompt and aggressive management, a full recovery can be expected.     

Preoperative Imaging for Resectable Periampullary Cancer: Clinicopathologic Implications of Reported Radiographic Findings

Background

High-resolution, multiphase, computed tomography (CT) is a standard preoperative test prior to pancreatectomy, yet the clinical significance of routinely reported findings remains unknown.

Methods

We identified patients who underwent a pancreaticoduodenectomy for a periampullary adenocarcinoma (PA) over the previous 5 years and had a pancreas protocol CT at our institution. Clinicopathologic implications of reported CT findings were evaluated.

Results

There were 155 pancreatic ductal adenocarcinomas (PDA) and 47 non-pancreatic PAs. No mass was visualized on CT in 6 % of PDAs and 23 % of non-pancreatic PA. A size discrepancy of ≥1 cm between radiographic and pathologic tumor diameters was observed in 40 % of PAs, with CT underestimating the size in most instances (75 %). Radiographically enlarged lymph nodes were not associated with true lymph node metastases in PDAs (70 % lymph node positive cases were enlarged on CT vs 74 % lymph node negative, p = 0.5), but were associated with a preoperatively placed biliary endoprosthesis (63 % with endoprosthesis were enlarged vs 37 % no endoprosthesis, p = 0.013). Major visceral vessel involvement on CT was not associated with a vascular resection (3 % with CT vessel involvement vs 2 % without, p = 0.8) or a positive uncinate resection margin (24 vs 20 %, respectively, p = 0.6).

Discussion

While dedicated pancreas protocol CT provides unprecedented detail, the test may lead to overinterpretation of the extent of disease in some instances. A radiographic suggestion of enlarged lymph nodes and vascular involvement does not necessarily preclude exploration with curative intent. CTs with local disease should be reported in an objective template and carefully reviewed by a multidisciplinary group of surgeons, radiologists, and oncologists to avoid missing an opportunity for neoadjuvant therapy or cure by resection.     

Interferon-inducible protein-10 identified as a mediator of tumor necrosis in vivo

Human Burkitt lymphoma cell lines give rise to progressively growing subcutaneous tumors in athymic mice. These tumors are induced to regress by inoculation of Epstein–Barr virus-immortalized normal human lymphocytes. In the present study, analysis of profiles of murine cytokine/chemokine gene expression in Burkitt tumor tissues excised from the nude mice showed that expression of the murine α-chemokine interferon-inducible protein-10 (IP-10) was higher in the regressing than in the progressive Burkitt tumors. We tested the effects of IP-10 on Burkitt tumor growth in nude mice. Inoculation of established Burkitt tumors either with crude preparations of murine IP-10 or with purified human IP-10 caused visible tumor necrosis in a proportion of the animals, although no complete tumor regressions were observed. Constitutive expression of murine IP-10 in Burkitt cells reduced their ability to grow as subcutaneous tumors, and caused visible tumor necrosis in a proportion of the animals. Histologically, IP-10-treated and IP-10-expressing Burkitt tumors had widespread evidence of tumor tissue necrosis and of capillary damage, including intimal thickening and vascular thrombosis. Thus, IP-10 is an antitumor agent that promotes damage in established tumor vasculature and causes tissue necrosis in human Burkitt lymphomas established subcutaneously in athymic mice.     

Gender- and race-specific comparison of tobacco-associated cancer incidence trends in Florida with SEER regional cancer incidence data

OBJECTIVE: Analysis of state and national tobacco-associated cancer trends is critical for the identification of high-risk regions of the country that require the attention of the public health community. This study compares Florida race- and gender-specific cancer trends with pooled data obtained from nine Surveillance, Epidemiology, and End Results (SEER-9) registries. METHODS: Age-adjusted, race- and gender-specific cancer incidence trends were evaluated using joinpoint regression analysis. Pooled, age-adjusted incidence rates and standardized incidence rate ratios were computed for each cancer for the years 1999-2003 to compare Florida to SEER-9. RESULTS: Relative to SEER-9 whites and irrespective of gender, lung cancer rates in white Floridians were elevated through the 1990s. However, lung cancer rates have recently declined at a steeper rate among white Floridians than among SEER-9 whites. For years 1999-2003, black Floridians had significantly lower rates of lung, bladder, pancreas, and kidney cancer relative to SEER-9 blacks. The opposite pattern was evident for white Floridians with significantly higher rates of lung and laryngeal cancer relative to SEER-9 whites. CONCLUSION: Progress in the reduction of tobacco-associated cancers among white Floridians lags behind the progress noted in SEER-9 registries suggesting that additional state-directed smoking prevention and smoking cessation measures are needed.     

Temporal CT changes after hepatic and renal interstitial radiotherapy in a canine model

PURPOSE: The purpose of this work was to define the temporal CT characteristics of hepatic and renal ablation following point-source radioablation utilizing a low energy, photon X-ray source emitted from a miniature probe. METHOD: Twelve mongrel dogs underwent each of three hepatic and two renal point-source radiation ablations. Animals underwent serial, dual phase, spiral CT scans and were killed at 1, 3, and 6 months after treatment. RESULTS: Ablative lesions were clearly visible at 1 month following therapy and consistently diminished in size over the 6 months of follow-up. Lesion size tended to be proportional to dose delivered. Both hepatic and renal lesions were low in attenuation with frequent rim enhancement that diminished over time. Hepatic lesions frequently showed transient hepatic attenuation differences (THADs). Lesion size appeared independent of proximity to vessels. CONCLUSION: Following hepatic or renal interstitial radiotherapy, lesions are generated that are similar in CT appearance to those produced by other ablative techniques. The presence of rim or THAD enhancement can be seen early on as part of the normal tissue-healing response.     

Tuberculosis presenting as a perirectal mass

The epidemic of acquired immunodeficiency syndrome has caused a worldwide resurgence of tuberculosis. A case of acute tuberculosis with anorectal involvement presenting at an urban American hospital is discussed. Although anorectal involvement by tuberculosis is not uncommon, the diagnosis is usually initially missed.