Esophageal submucosa: The watershed for esophageal cancer

ObjectivesSubmucosal esophageal cancers (pT1b) are considered superficial, implying good survival. However, some are advanced, metastasizing to regional lymph nodes. Interplay of cancer characteristics and lymphatic anatomy may create a watershed, demarcating low-risk from high-risk cancers. Therefore, we characterized submucosal cancers according to depth of invasion and identified those with high likelihood of lymph node metastases and poor survival.MethodsFrom 1983 to 2010, 120 patients underwent esophagectomy for submucosal cancers at Cleveland Clinic. Correlations were sought among cancer characteristics (location, dimensions, histopathologic cell type, histologic grade, and lymphovascular invasion [LVI]), and their associations with lymph node metastasis were identified by logistic regression. Associations with mortality were identified by Cox regression.ResultsAs submucosal invasion increased, cancer length (P < .001), width (P < .001), area (P < .001), LVI (P = .007), and grade (P = .05) increased. Invasion of the deep submucosa (P < .001) and LVI (P = .06) predicted lymph node metastases: 45% (23/51) of deep versus 10% (3/29) of middle-third and 7.5% (3/40) of inner-third cancers had lymph node metastases, as did 46% (12/26) with LVI versus 18% (17/94) without. Older age and lymph node metastases predicted worse 5-year survival: 94% for younger pN0 patients, 62% for older pN0 patients, and 36% for pN1-2 patients regardless of age.ConclusionsSubmucosal cancer characteristics and lymphatic anatomy create a watershed for regional lymph node metastases in the deep submucosa. This previously unrecognized divide distinguishes superficial submucosal cancers with good survival from deep submucosal cancers with poor survival. Aggressive therapy of more superficial cancers is critical before submucosal invasion occurs

Fate of the esophagogastric anastomosis

ObjectiveThe study objective was to evaluate histopathology of the esophagogastric anastomosis after esophagectomy, determine time trends of histologic changes, and identify factors influencing those findings.MethodsA total of 231 patients underwent 468 upper gastrointestinal endoscopies with anastomotic biopsy a median of 3.5 years after esophagectomy. Mean age was 59 ± 12 years, 74% (171) were male, and 96% (222) were white. Seventy-eight percent (179) had esophagectomy for cancer, 13% (30) had chemoradiotherapy, and 13% (30) had prior esophageal surgery. The anastomosis was 20 ± 2.0 cm from the incisors. Anti-reflux medications were used in 59% of patients (276/468) at esophagoscopy. Histopathology was graded as normal (0), consistent with reflux (1), cardia mucosa (2), intestinal metaplasia (3), and dysplasia (4). Repeated-measures nonlinear time-trend analysis and multivariable analyses were used.ResultsGrades 0 and 1 were constant, 5% and 92% at 10 years, respectively. Anti-reflux medication, induction therapy, and higher anastomosis were predictive of less grade 1 histopathology. Grades 2 and 3 increased with time: 12% and 33% at 5 years and 4% and 16% at 10 years, respectively. No variable was predictive of grade 2 or 3 (P > .15) except passage of time. No patient’s condition progressed to dysplasia or cancer.ConclusionsThe esophagogastric anastomosis is subject to gastroesophageal reflux. To minimize histopathologic changes of reflux, the anastomosis should be constructed as high as possible (closer to incisors) and anti-reflux medications prescribed. Surveillance endoscopy, if performed, will document a time-related progression of reflux-related histopathologic changes. However, during surveillance, intestinal metaplasia is uncommon and progression to cancer rare

Pretransplant gastroesophageal reflux compromises early outcomes after lung transplantation

ObjectivesGastroesophageal reflux disease (GERD) is implicated as a risk factor for bronchiolitis obliterans syndrome after lung transplantation, but its effects on acute rejection, early allograft function, and survival are unclear. Therefore, we sought to systematically understand the time-related impact of pretransplant GERD on graft function (spirometry), mortality, and acute rejection early after lung transplantation.MethodsFrom January 2005 to July 2008, 215 patients underwent lung transplantation; 114 had preoperative pH testing, and 32 (28%) had objective evidence of GERD. Lung function was assessed by forced 1-second expiratory volume (FEV1; percent of predicted) in 97 patients, mortality by follow-up (median, 2.2 years), and acute rejection by transbronchial biopsy.ResultsPretransplant GERD was associated with decreased FEV1 early after lung transplantation (P = .01) such that by 18 months, FEV1 was 70% of predicted in double lung transplant patients with GERD versus 83% among non-GERD patients (P = .05). A similar decrease was observed in single lung transplantation (50% vs 60%, respectively; P = .09). GERD patients had lower survival early after transplant ( P = .02)—75% versus 90%. Presence of GERD did not affect acute rejection (P = .6).ConclusionsFor lung transplant recipients, pretransplant GERD is associated with worse early allograft function and survival, but not increased acute rejection. The compromise in lung function is substantial, such that FEV1 after double lung transplant in GERD patients approaches that of single lung transplant in non-GERD patients. We advocate thorough testing for GERD before lung transplantation; if identified, aggressive therapy early after transplant, including fundoplication, may prove efficacious

Studies into the mechanism of action of interleukin 3 : purification of interleukin 3 and characterization of its cell surface receptor

Hemopoiesis is regulated, in part, by a group of potent, soluble hemopoietic growth factors. One of these growth factors, interleukin 3, stimulates the proliferation and differentiation of both multi-potential hemopoietic stem cells and maturing committed progenitors, and may thus play a central role in regulating hemopoiesis in vivo. Studies of the mechanism of action of this hemopoietic growth factor may therefore yield valuable insights into normal hemopoietic differentiation and provide an understanding of the pathogenesis of hemopoietic malignancies. In order to begin these studies, it was first necessary to devise a simple high yield purification procedure for murine interleukin 3, since published purification protocols were lengthy and resulted in unacceptably low yields. A simple and rapid 3-step procedure was therefore devised which greatly facilitated our studies. The novel aspect of this procedure involved the treatment of B6SUtA₁ cells with 0.01% glutaraldehyde which transformed them into mechanically resistant spheres. This made it possible to use these high interleukin 3 receptor-expressing cells as a solid phase reagent suitable for the large scale purification of interleukin 3. Purification, using these fixed cells and two standard purification steps, resulted in a 16,000-fold enrichment and purification to apparent homogeneity of interleukin 3 from serum-free pokeweed mitogen stimulated spleen cell conditioned medium. The effects of pure interleukin 3 on interleukin 3 receptor internalization and re-expression and the relationship between interleukin 3 receptor surface density and growth factor sensitivity were then examined. From these studies, it was demonstrated that surface bound interleukin 3 is rapidly internalized and cleaved at two specific sites, before being completely digested within lysosomes. However, unlike its ligand, the interleukin 3 receptor appears to be recycled to the cell surface without proteolytic cleavage. Furthermore, receptor re-expression is critically dependent upon the extracellular concentration of interleukin 3. More importantly, in the absence of interleukin 3, target cells express extremely high levels of surface receptor and become exquisitely sensitive to interleukin 3. iii Finally, the structure of the interleukin 3 receptor was examined. Previous the precise nature of the interleukin 3 receptor have proven particularly molecular weight estimates for the receptor have been forwarded. Through crosslinking agents, this controversy appears to have been resolved. A model generated suggests that the interleukin 3 receptor is a 140 kd membrane 3 binding and chemical crosslinking, becomes proteolytically cleaved to a 70kd surface protein.Medicine, Faculty ofPathology and Laboratory Medicine, Department ofGraduat

An examination of in vitro erythropoiesis by utilizing agents that mimic the in vitro activity of erythropoietin

The major in vivo hormonal regulator of terminal erythropoiesis is erythropoietin (Ep). This 38,000 dalton acidic glycoprotein has been shown to stimulate the formation of hemoglobinizing erythroblasts. Two in vitro assays designed to measure Ep bioactivity were utilized to determine if other agents could mimic Ep activity in vitro. It was hoped that this approach might yield insights into the mechanism of action of Ep. Several agents have now been identified, and two, dimethyl sulfoxide (DMSO) and sodium orthovanadate had previously been shown (in other systems) to stimulate membrane phosphorylation changes. Accordingly, Ep, DMSO and sodium orthovanadate were assayed with Ƴ-³²P-ATP and plasma membranes purified from Ep-responsive cells to determine if each could induce significant phosphorylation changes as assessed by sodium dodecyl sulfate polyacrylamide gel electrophoresis and autoradiography. It was found that while both sodium orthovanadate and DMSO effected profound phosphorylation alterations, Ep did not elicit any detectable phosphorylation changes. Specifically, vanadate caused a generalized increase in membrane base-stable phosphoproteins, and DMSO reproducibly stimulated the base resistant phosphorylation of a 35 Kd membrane-associated protein. It is reasonable to postulate that the latter phosphorylation event might be responsible for the stimulatory activity of DMSO on terminally differentiating erythroid cells. To understand whether Ep and Ep-mimicking agents were operative on the same target cell population, homogeneous, virally-infected, erythroblasts were cultured in vitro and assayed for ³H-thymidine incorporation in the presence of each agent at various intervals during erythroid cell differentiation. It was found that Ep greatly stimulated very early, as well as differentiated, erythroblasts to proliferate, while four different Ep-mimicking agents could only effect thymidine incorporation into a more mature erythroid population. From this work it is conceivable that Ep-mimicking agents stimulate in vitro erythropoiesis through specific membrane phosphorylation changes and function primarily on late erythroblasts, while the mechanism of action of Ep on primitive and late erythroblasts remains unresolved.Medicine, Faculty ofPathology and Laboratory Medicine, Department ofGraduat