Th17 cell inhibition in a costimulation blockade-based regimen for vascularized composite allotransplantation using a nonhuman primate model

Vascularized composite allotransplantation (VCA) is challenged by the morbidity of immunosuppression required to prevent rejection. The use of highly specific biologics has not been well explored in VCA. Given that psoriasis is T-cell mediated, as is rejection of skin-containing VCAs, we sought to assess the role of ustekinumab and secukinumab, which are approved to treat psoriasis by inhibiting Th17 cells. We combined these agents with belatacept and steroids in a VCA nonhuman primate model. Group I consisted of belatacept and steroids, group II was belatacept, ustekinumab with steroid taper, and group III was belatacept, secukinumab with steroid taper. Three animals were transplanted in each group. In group I, the mean graft survival time until the first sign of rejection was 10 days whereas in group II and III it was 10.33 and 11 days, respectively. The immunohistochemistry analysis showed that the number of IL-17a⁺ cells and the intensity of IL-17a expression were significantly reduced in both dermis and hypodermis parts in groups II and III when compared to group I (P < 0.01). Ustekinumab and secukinumab led to less T-cell infiltration and IL-17a expression in the allograft but provided no benefit to belatacept and steroids in VCA survival.

Secondary lymphoid tissue and costimulation-blockade resistant rejection: A nonhuman primate renal transplant study

Naïve T cell activation requires antigen presentation combined with costimulation through CD28, both of which optimally occur in secondary lymphoid tissues such as lymph nodes and the spleen. Belatacept impairs CD28 costimulation by binding its ligands, CD80 and CD86, and in doing so, impairs de novo alloimmune responses. However, in most patients belatacept is ineffective in preventing allograft rejection when used as a monotherapy, and adjuvant therapy is required for control of costimulation-blockade resistant rejection (CoBRR). In rodent models, impaired access to secondary lymphoid tissues has been demonstrated to reduce alloimmune responses to vascularized allografts. Here we show that surgical maneuvers, lymphatic ligation, and splenectomy, designed to anatomically limit access to secondary lymphoid tissues, control CoBRR and facilitate belatacept monotherapy in a nonhuman primate model of kidney transplantation without adjuvant immunotherapy. We further demonstrate that animals sustained on belatacept monotherapy progressively develop an increasingly naïve T and B cell repertoire, an effect that is accelerated by splenectomy and lost at the time of belatacept withdrawal and rejection. These pilot data inform the role of secondary lymphoid tissues on the development of CoBRR and the use of costimulation molecule-focused therapies.

Corticosteroids and methotrexate as adjuvants to costimulation blockade in non-human primate renal transplantation

Belatacept, the CD28-B7 costimulation pathway inhibitor, has been approved as a calcineurin inhibitor (CNI) alternative in kidney transplantation. Although costimulation blockade (CoB) allows for CNI avoidance, it is associated with increased rates of early rejection, prompting a search for agents to pair with belatacept. Methotrexate (MTX) is an antimetabolite that has been found to be complimentary with abatacept, a lower affinity CD28-B7-specific analogue of belatacept, in the treatment of rheumatoid arthritis (RA). We examined whether this synergy would extend to prevention of kidney allograft rejection. Rhesus macaques underwent kidney transplantation treated with abatacept maintenance therapy with either a steroid taper, MTX, or both. The combination of abatacept maintenance with steroids prolonged graft survival compared to untreated historical controls and previous reports of abatacept monotherapy. The addition of MTX did not provide additional benefit. These data demonstrate that abatacept with adjuvant therapy may delay the onset of acute rejection, but fail to show synergy between abatacept and MTX beyond that of steroids. These findings indicate that MTX is unlikely to be a suitable adjuvant to CoB in kidney transplantation, but also suggest that with further modification, a CoB regimen used for advanced RA may suffice for RA patients requiring kidney transplantation.

Anti-Leukocyte Function-Associated Antigen 1 Therapy in a Nonhuman Primate Renal Transplant Model of Costimulation Blockade-Resistant Rejection

Costimulation blockade with the fusion protein belatacept provides a desirable side effect profile and improvement in renal function compared with calcineurin inhibition in renal transplantation. This comes at the cost of increased rates of early acute rejection. Blockade of the integrin molecule leukocyte function-associated antigen 1 (LFA-1) has been shown to be an effective adjuvant to costimulation blockade in a rigorous nonhuman primate (NHP) model of islet transplantation; therefore, we sought to test this combination in an NHP renal transplant model. Rhesus macaques received belatacept maintenance therapy with or without the addition of LFA-1 blockade, which was achieved using a murine-derived LFA-1-specific antibody TS1/22. Additional experiments were performed using chimeric rhesus IgG1 (TS1/22R1) or IgG4 (TS1/22R4) variants, each engineered to limit antibody clearance. Despite evidence of proper binding to the target molecule and impaired cellular egress from the intravascular space indicative of a therapeutic effect similar to prior islet studies, LFA-1 blockade failed to significantly prolong graft survival. Furthermore, evidence of impaired protective immunity against cytomegalovirus was observed. These data highlight the difficulties in translating treatment regimens between organ models and suggest that the primarily vascularized renal model is more robust with regard to belatacept-resistant rejection than the islet model.

Inhibition of αvβ6 promotes acute renal allograft rejection in nonhuman primates

The integrin αvβ6 activates latent transforming growth factor-β (TGF-β) within the kidney and may be a target for the prevention of chronic allograft fibrosis after kidney transplantation. However, TGF-β also has known immunosuppressive properties that are exploited by calcineurin inhibitors (CNIs); thus, the net benefit of αvβ6 inhibition remains undetermined. To assess the acute impact of interference with αvβ6 on acute rejection, we tested a humanized αvβ6-specific monoclonal antibody (STX-100) in a randomized, double-blinded, placebo-controlled nonhuman primate renal transplantation study to evaluate whether αvβ6 blockade alters the risk of acute rejection during CNI-based immunosuppression. Rhesus monkeys underwent renal allotransplantation under standard CNI-based maintenance immunosuppression; 10 biopsy-confirmed rejection-free animals were randomized to receive weekly STX-100 or placebo. Animals treated with STX-100 experienced significantly decreased rejection-free survival compared to placebo animals (p = 0.049). Immunohistochemical analysis confirmed αvβ6 ligand presence, and αvβ6 staining intensity was lower in STX-100-treated animals (p = 0.055), indicating an apparent blockade effect of STX-100. LAP, LTBP-1 and TGF-β were all decreased in animals that rejected on STX-100 compared to those that rejected on standard immunosuppression alone, suggesting a relevant effect of αvβ6 blockade on local TGF-β. These data caution against the use of αvβ6 blockade to achieve TGF-β inhibition in kidney transplantation.

Belatacept and sirolimus prolong nonhuman primate renal allograft survival without a requirement for memory T cell depletion

Belatacept is an inhibitor of CD28/B7 costimulation that is clinically indicated as a calcineurin inhibitor (CNI) alternative in combination with mycophenolate mofetil and steroids after renal transplantation. We sought to develop a clinically translatable, nonlymphocyte depleting, belatacept-based regimen that could obviate the need for both CNIs and steroids. Thus, based on murine data showing synergy between costimulation blockade and mTOR inhibition, we studied rhesus monkeys undergoing MHC-mismatched renal allotransplants treated with belatacept and the mTOR inhibitor, sirolimus. To extend prior work on costimulation blockade-resistant rejection, some animals also received CD2 blockade with alefacept (LFA3-Ig). Belatacept and sirolimus therapy successfully prevented rejection in all animals. Tolerance was not induced, as animals rejected after withdrawal of therapy. The regimen did not deplete T cells. Alefecept did not add a survival benefit to the optimized belatacept and sirolimus regimen, despite causing an intended depletion of memory T cells, and caused a marked reduction in regulatory T cells. Furthermore, alefacept-treated animals had a significantly increased incidence of CMV reactivation, suggesting that this combination overly compromised protective immunity. These data support belatacept and sirolimus as a clinically translatable, nondepleting, CNI-free, steroid-sparing immunomodulatory regimen that promotes sustained rejection-free allograft survival after renal transplantation.

Enhanced de novo alloantibody and antibody-mediated injury in rhesus macaques

Chronic allograft rejection is a major impediment to long-term transplant success. Humoral immune responses to alloantigens are a growing clinical problem in transplantation, with mounting evidence associating alloantibodies with the development of chronic rejection. Nearly a third of transplant recipients develop de novo antibodies, for which no established therapies are effective at preventing or eliminating, highlighting the need for a nonhuman primate model of antibody-mediated rejection. In this report, we demonstrate that depletion using anti-CD3 immunotoxin (IT) combined with maintenance immunosuppression that included tacrolimus with or without alefacept reliably prolonged renal allograft survival in rhesus monkeys. In these animals, a preferential skewing toward CD4 repopulation and proliferation was observed, particularly with the addition of alefacept. Furthermore, alefacept-treated animals demonstrated increased alloantibody production (100%) and morphologic features of antibody-mediated injury. In vitro, alefacept was found to enhance CD4 effector memory T cell proliferation. In conclusion, alefacept administration after depletion and with tacrolimus promotes a CD4+memory T cell and alloantibody response, with morphologic changes reflecting antibody-mediated allograft injury. Early and consistent de novo alloantibody production with associated histological changes makes this nonhuman primate model an attractive candidate for evaluating targeted therapeutics.

A novel monoclonal antibody to CD40 prolongs islet allograft survival

The importance of CD40/CD154 costimulatory pathway blockade in immunosuppression strategies is well-documented. Efforts are currently focused on monoclonal antibodies specific for CD40 because of thromboembolic complications associated with monoclonal antibodies directed towards CD154. Here we present the rational development and characterization of a novel antagonistic monoclonal antibody to CD40. Rhesus macaques were treated with the recombinant anti-CD40 mAb, 2C10, or vehicle before immunization with keyhole limpet hemocyanin (KLH). Treatment with 2C10 successfully inhibited T cell-dependent antibody responses to KLH without significant peripheral B cell depletion. Subsequently, MHC-mismatched macaques underwent intraportal allogeneic islet transplantation and received basiliximab and sirolimus with or without 2C10. Islet graft survival was significantly prolonged in recipients receiving 2C10 (graft survival time 304, 296, 265, 163 days) compared to recipients receiving basiliximab and sirolimus alone (graft survival time 8, 8, 10 days). The survival advantage conferred by treatment with 2C10 provides further evidence for the importance of blockade of the CD40/CD154 pathway in preventing alloimmune responses. 2C10 is a particularly attractive candidate for translation given its favorable clinical profile.

Alternative immunomodulatory strategies for xenotransplantation: CD40/154 pathway-sparing regimens promote xenograft survival

Immunosuppressive therapies that block the CD40/CD154 costimulatory pathway have proven to be uniquely effective in preclinical xenotransplant models. Given the challenges facing clinical translation of CD40/CD154 pathway blockade, we examined the efficacy and tolerability of CD40/CD154 pathway-sparing immunomodulatory strategies in a pig-to-nonhuman primate islet xenotransplant model. Rhesus macaques were rendered diabetic with streptozocin and given an intraportal infusion of ≈ 50 000 islet equivalents/kg wild-type neonatal porcine islets. Base immunosuppression for all recipients included maintenance therapy with belatacept and mycophenolate mofetil plus induction with basiliximab and LFA-1 blockade. Cohort 1 recipients (n = 3) were treated with the base regimen alone; cohort 2 recipients (n = 5) were additionally treated with tacrolimus induction and cohort 3 recipients (n = 5) were treated with alefacept in place of basiliximab, and more intense LFA-1 blockade. Three of five recipients in both cohorts 2 and 3 achieved sustained insulin-independent normoglycemia (median rejection-free survivals 60 and 111 days, respectively), compared to zero of three recipients in cohort 1. These data show that CD40/CD154 pathway-sparing regimens can promote xenoislet survival. Further optimization of these strategies is warranted to aid the clinical translation of islet xenotransplantation.

Islet xenotransplantation using gal-deficient neonatal donors improves engraftment and function

Significant deficiencies in understanding of xenospecific immunity have impeded the success of preclinical trials in xenoislet transplantation. Although galactose-α1,3-galactose, the gal epitope, has emerged as the principal target of rejection in pig-to-primate models of solid organ transplant, the importance of gal-specific immunity in islet xenotransplant models has yet to be clearly demonstrated. Here, we directly compare the immunogenicity, survival and function of neonatal porcine islets (NPIs) from gal-expressing wild-type (WT) or gal-deficient galactosyl transferase knockout (GTKO) donors. Paired diabetic rhesus macaques were transplanted with either WT (n = 5) or GTKO (n = 5) NPIs. Recipient blood glucose, transaminase and serum xenoantibody levels were used to monitor response to transplant. Four of five GTKO versus one of five WT recipients achieved insulin-independent normoglycemia; transplantation of WT islets resulted in significantly greater transaminitis. The WT NPIs were more susceptible to antibody and complement binding and destruction in vitro. Our results confirm that gal is an important variable in xenoislet transplantation. The GTKO NPI recipients have improved rates of normoglycemia, likely due to decreased susceptibility of xenografts to innate immunity mediated by complement and preformed xenoantibody. Therefore, the use of GTKO donors is an important step toward improved consistency and interpretability of results in future xenoislet studies.

Shape and volume of internal anal sphincter showed by three-dimensional anorectal ultrasonography

PURPOSE

The aim of this work is to characterize the shape and the volume of the internal anal sphincter (IAS) in normal subjects by three-dimensional anorectal ultrasonography.

METHODS

Thirty-nine normal volunteer males (mean age 58.5 ± 18.7) and 25 females (mean age 59.4 ± 14.1) were submitted to anorectal ultrasonography. The tissue is defined by a semiautomatic procedure. Measurements of thickness, length and volume were assessed automatically. The software provides an average number of 57,600 thickness measurements, 360 length measurements for each zone (90 for each quadrant) and seven volume measurements (one for each anatomical area).The mean values of magnitudes were calculated for the entire volume in each quadrant and zone. Age and gender-related variations were analyzed.

RESULTS

In assessments of the whole tissue, only thickness was gender-related, with greater thickness for females (male thickness: 1.81 ± 0.47 mm, female thickness 2.16 ± 0.57 mm, P-value<0.01).In the distal zone: thickness, length and volume were all larger in females (for male and female respectively: 1.83 ± 0.49 mm vs 2.34 ± 0.58 mm, P-value<0.01, for the thickness; 10.87 ± 2.10mm vs 12.18 ± 2.21 mm, P-value<0.02 for the length and 1501 ± 605 mm(3) vs 2169 ± 871 mm(3), P-value<0.01 for the volume). In the medial zone, only thickness was gender-related, with greater thickness in females (male thickness: 2.04 ± 0.60mm, female thickness:2.44 ± 0.74 mm, P-value<0.02).The only variation observed in the proximal zone concerned length, larger in males (respectively: 11.27 ± 2.84 mm vs 9.55 ± 2.43 mm, P-value<0.02). The male population was significantly positively correlated with ageing for volume in the whole tissue (ρ = 0.32, P-value<0.05), and for both thickness and volume in the medial zone (ρ = 0.33, P-value<0.05 for thickness; ρ = 0.39, P-value<0.02 for the volume).

CONCLUSION

This new method is useful to understand both functional anal disorders and local damage which may affect only part of the muscle tissue.

[Perianal Paget's disease: five cases report]

AIM

Extramammary Paget's disease is a rare neoplastic condition, often associated with a synchronous or metachronous underlying skin or visceral malignancies. The aim of this study was to evaluate retrospectively the results we got in 5 cases of perianal Paget's disease and to revise what literature have reported about this issue.

PATIENTS AND METHODS

Five patients with perianal EMPD were consecutively treated in our Division between March 1996 and December 2006. In 3 cases the disease was limited to the epidermidis, in one case with multiple recurrences there was dermal infiltration, and one patient had a low rectal adenocarcinoma with pagetoid phenomenon. The surgical treatment we performed in all patients was a wide perianal excision, followed by reconstruction with cutaneous grafts; the resection of rectal adenocarcinoma was carried out using the transanal approach. In two cases we performed a temporary stoma with the sigmoid colon to help the wound healing.

RESULTS

We didn't record any complication neither postoperative nor at long time. Two patients developed a local recurrence, but none of our patients showed distant metastases. Four patients are alive and free from disease and one, who developed a multiple local recurrences, died for heart failure.

DISCUSSION

The studies available in literature clearly distinguish between a primary EMPD (intraepidermal/intradermal) and secondary disease which is associated with anorectal adenocarcinomas and is thought to be a pagetoid phenomenon, while few informations can derive from those cases in which the disease is associated with an underlying cutaneous adnexal carcinoma. Disease tend to relapse even after a radical surgery and can have metastatic spread, also in intraepidermal form.

CONCLUSIONS

Perianal EMPD is a complex disease, difficult to recognize and the association with synchronous or metachronous malignancies imposes long term clinical and instrumental follow up.

Treatment of abdominal aortic aneurysm associated with colorectal cancer: presentation of 14 cases and literature review

PURPOSE

The coexistence of abdominal aortic aneurysm (AAA) and cancer is observed with increasing frequency, raising several questions about therapeutic and surgical strategies for management of both diseases. In this study, we present our experience on 14 patients affected by both colorectal cancer (CRC) and AAA, and we have also reviewed the literature from 1988 to 2005 for clinical experiences on this matter.

MATERIALS AND METHODS

From January 1988 to May 2006, 1,012 AAA and 1,480 CRC were observed and treated in our department; in 14 patients (1.3% of AAA and 0.9% of CRC), both diseases were coexistent. We also performed a literature review from 1987 to 2005, and we found 254 cases of AAA associated with CRC.

RESULTS

Priority was given for treatment of vascular disease. The diseases were treated in one stage in nine cases and in two stage in four patients; in the remaining case, only the CRC was treated due to patient's poor cardiac conditions. Postoperative (30-day) complications were seen in 1 of 14 patients (7.1%), whereas there were no postoperative deaths or prosthetic infections. In the literature review, treatment in one stage was performed in 102 cases and in two stage in 118 cases; in the remaining 25 cases, only one disease was treated (in 24 cases, for different reasons, only CRC was treated, whereas in the last case, only the AAA was treated, and the patient died in the postoperative period). Postoperative (30-day) morbidity and mortality in one-stage treatment were 8 and 4.5%, respectively, and 21.3 and 6% in two-stage treatments, respectively. In patients treated for only one disease, 30-day morbidity and mortality were 4 and 24%, respectively. Only one case of prosthetic infection was reported after a two-stage treatment.

CONCLUSIONS

From the analysis of the literature and our experience, it is evident that, when AAA and CRC are coexistent with preoperative diagnosis of both diseases, single-stage intervention, when feasible for patient in general and local conditions, has to be preferred due to the lower morbidity. Single-stage treatment avoids a second surgical and anesthesiologic trauma and eliminates the risks joined with the non-treated lesion, increasing, however, the magnitude of the operation. Endovascular therapy, for its less invasiveness, appears to be an adequate solution for one-stage treatment of the two diseases but its role is still subject of ongoing discussions.

[Metachronus splenic metastasis of colon cancer. A case report]

Colon cancer metastases rarely involve the spleen; in the literature only 29 cases of isolated splenic metastasis of colon cancer are reported (9 in the English literature and 29 in the Japanese literature). In this paper, a further case of isolated splenic metastasis in a 73 year- old woman, treated six years before with left emicolectomy for a mucinous colon cancer (Dukes B) is reported. A survey of the English literature shows that most of the cases had a significant period between the first original resection and the diagnosis of spleen metastasis (2-11 years). Splenectomy was performed in all the cases reported. No long-term follow-up has been published; therefore, it is not possible to define if spleen metastases of colon cancer have a better clinical behaviour than hepatic metastases and if splenectomy can prevent metastatic spreading of the disease leading to a potential survival benefit.

Bucrylate treatment of bleeding gastric varices: 12 years' experience

BACKGROUND AND STUDY AIMS

For several years now there has been an increasingly widespread use of a tissue adhesive in the treatment of bleeding gastric varices to achieve rapid, safe control of hemostasis and prevent rebleeding. In this study we report on our experience with the use of Bucrylate (Hystoacryl) for the treatment of gastric varices over a period of more than a decade.

PATIENTS AND METHODS

Since 1988, 174 cirrhotic patients with actively bleeding gastric varices have been admitted to our department, where they received emergency treatment with injections of Bucrylate. Any associated nonbleeding esophageal varices were subjected to traditional sclerotherapy in combination with the Bucrylate treatment. The gastric varices were subdivided into four distinct groups according to the method advocated by Sarin in 1989. The patients underwent weekly sclerotherapy sessions until their varices were eradicated, and the follow-up with a mean of 36 months (range 9-90 months) consisted of endoscopy at 3, 6, and 12 months during the first year and then yearly checks to confirm obliteration of the varices.

RESULTS

The hemostasis (97.1%), early rebleeding (15.5%), and hospital mortality (19.5%) rates of the patients with bleeding gastric varices, treated with the tissue adhesive, were very similar to those of patients treated for esophageal varices over the same period (98.1%, 13.0%, and 16.4%, respectively). The most frequent cause of death at 30 days was liver failure (76% of cases), followed by hemorrhagic shock (8.8%), and other less frequent causes. Sclerotherapy achieved obliteration rate for gastric varices (70-75%) similar to that for esophageal varices in those patients with portal hypertension due to intrahepatic block (alcoholic and posthepatitis cirrhosis), but a rate of only 32% in the group of patients with prehepatic block (splenoportomesenteric thrombosis), where surgery proved more effective (69%). The medium- and long-term survival rates depended on the stability of the patients' liver conditions, on rapid, effective control of variceal hemostasis, and on complete, lasting obliteration of the gastric varices.

CONCLUSIONS

The use of Bucrylate in emergency sclerotherapy achieved results in bleeding gastric varices on a par with those obtained in esophageal varices in cases of alcoholic and posthepatitis cirrhosis. The group of patients with portal hypertension due to prehepatic block (splenoportal thrombosis) showed no benefit from sclerotherapy in terms of obliteration of gastric varices, but benefited from elective surgery. The choice of the obliterating treatment indicated may be facilitated by classifying gastric varices into distinct groups on the basis of anatomicotopographic criteria.

[Results of preoperative staging using endosonography in rectal cancer]

BACKGROUND AND AIM

The latest reports using transrectal ultrasound (TRUS) for the preoperative staging of rectal cancer show a diagnostic accuracy between 78 and 97% with regard to the local spread of disease, and between 62 and 86% for the diagnosis of lymph node metastasis. The correct choice of surgery depends on correct preoperative staging, as does the indication for any preoperative neoadjuvant treatment. The aim of this study was to evaluate the diagnostic precision of the method used by the authors since 1993 by comparing the preoperative transrectal ultrasound stage (uTMN) with the postoperative histological stage (pTNM). In addition, the study aimed to assess whether some anatomic and pathological characteristics of the neoplasm (differentiation, type of growth and presence of peritumoral inflammatory reaction) influenced the diagnostic precision of transrectal ultrasonography.

METHODS

Forty-two patients with a preoperative histological diagnosis of adenocarcinoma localised in the rectal segment, extending up to 10 cm from the dentate line, undergoing radical surgical were selected from the group of patients with middle-lower rectal cancer studied preoperatively with TRUS. Preoperative TRUS was carried out in 42 cases by a single examiner. Anatomic and pathological examination of the removed portion was performed by examiners who were not familiar with the preoperative ultrasonographic diagnosis.

RESULTS

In this study TRUS showed a diagnostic accuracy of 81% in the study of T and 71.4% in the study of N. In line with other studies, the most frequent diagnostic error was the overstaging of stage T2 tumours. Moreover, the presence of a peritumoral inflammatory reaction was found to be the only variable that significantly influenced the diagnostic accuracy of TRUS.

CONCLUSIONS

TRUS was found to be a valid instrument for the preoperative staging of rectal cancer even in this preliminary study limited to 42 cases, in particular with regard to wall invasion. The limits of this method are linked to the presence of phenomena producing a situation of local infection (recent biopsies, radiotherapy, peritumoral inflammatory infiltrate) given that this prevented the correct visualisation of the layers of the rectal wall. As a result, this may limit its use in the re-staging of patients undergoing preoperative radiotherapy.

[Abdominal metastasis of cardias adenocarcinoma]

BACKGROUND

The aim of the present study was to evaluate the incidence of abdominal lymph node involvement of adenocarcinoma of the gastric cardia in relationship with the site and depth of tumor invasion.

METHODS

From July 1988 to April 1998, 79 patients with adenocarcinoma of the gastric cardia underwent surgical curative resection and D2 lymphadenectomy at the 1st Department of General Surgery of Verona University. Among these 79 patients, 16 had an adenocarcinoma of the distal esophagus (type I), 26 patients had an adenocarcinoma of the anatomic cardia (type II) and 37 had a subcardial adenocarcinoma (type III). The frequency of lymph node involvement in each of the lymph nodes as classified by the JRSGC were analyzed.

RESULTS

In type I carcinoma positive lymph nodes occurred in 20% of pT1, 33% of pT2 and 100% of pT3. Positive nodes along the lower half of the stomach were never found. In type II carcinoma positive lymph nodes occurred in 57% of pT1, 86% of pT2 and 83% of pT3. Metastasis along the greater curvature in 18% of advanced cancers were found. In type III carcinoma positive lymph nodes occurred in 83% of pT2, 94% of pT3 and in 100% of pT4. Nodes along greater curvature were involved in 21% of advanced cases and also infrapyloric lymph nodes involved in 13% of cases. The type II and III advanced tumors had involved paraortic lymph node in 33% of cases.

CONCLUSIONS

These results suggest that for tumors of the cardia an extended lymphadenectomy is necessary to ensure the removal of all metastatic nodes.

[The surgery of abdominal aortic aneurysms synchronous with neoplastic lesions (apropos of 18 personal observations)]

The management of simultaneously occurring abdominal aortic aneurysm and malignancy is controversial. It is unclear whether to treat the aneurysm first or the malignancy, or both simultaneously. If the malignancy is resected first there is a risk of postoperative rupture of the aneurysm. If simultaneous surgery is performed there is a risk of prosthetic graft infection. This condition leads to many therapeutic problems which, by the light of 18 personal cases occurred in almost ten years and the recent literature, are discussed in this paper.

[Occlusion of the common iliac artery caused by mycotic endocarditis]

Mycotic endocarditis has an incidence of 6.7% of all the forms of endocarditis and in 33-75% of the cases it complicates with peripheral embolization, more frequently to the lower limbs. Although the prognosis of the mycotic endocarditis is improved in the last years, it remains particularly serious especially when it's associated with arterial peripheral embolization. The authors report their experience in the surgical treatment of one case of occlusion of the iliac artery secondary to mycotic endocarditis, making a review of the Literature on this matter.

[Salmonella C infection of aortic abdominal aneurysm]

The infected aneurysms of the aorta represent the 0.65% of all the aneurysms and they are associated with high morbidity and mortality. The vascular infections from Salmonella are not particularly frequent, even if in the last years their reports are more numerous. The authors report their experience in the surgical treatment of one case of aneurysm of the abdominal aorta infected by group C Salmonella, making a review of the Literature on this matter.

[Aneurysm of the celiac trunk. Presentation of a clinical case and review of the literature]

The aneurysms of the celiac trunk are the rarest aneurysms of the visceral arteries. From 1958 only 69 cases have been reported in the international literature. They are frequently asymptomatic and their discovery is more often occasional. They can rupture in 15-20% of the cases with a mortality approaching 80% of the cases. This explains the need of a surgical treatment even in the asymptomatic cases. Personal experience in the surgical treatment of a case of aneurysm of the celiac trunk is reported and a survey of the literature on this matter is made.

[Neurogenic tumors of the ano-rectal region]

Neurilemmoma and Neurofibroma are benign tumours of the peripheral nerves that originate from the Schwann Cells. The finding of these tumours in the gastrointestinal tract in absence of generalized neurofibromatosis is uncommon and their presence in the anorectal area is extremely rare. From review of the literature we found only 34 cases of anorectal neurilemmoma. We report two patients, one with a rectal neurilemmoma and another with a perianal neurofibroma without a coexisting Von Recklinghausen's disease in either. In both cases they were asymptomatic and the surgical procedure performed was the simple tumorectomy which was diagnostic and curative. The literature on this subject is reviewed with particular attention to the possible malignant degeneration and the choice of the surgical approaches.

[The perforation of a para-Vater's duodenal diverticulum (a report of 2 clinical cases)]

Duodenal diverticulum is not a rare disease, with a frequency of 1-3% in radiologic review and of 2.8-20% in pathology review; The spontaneous perforation of a perivaterian duodenal diverticulum is a rare complication, with about 100 cases reported in the literature. The post-traumatic perforation of a perivaterian diverticulum is an exceptional event, reported in single cases of the oriental literature. The authors report their personal experience about two cases of diverticular duodenal perforation, one spontaneous, the other post-traumatic, discussing the surgical problems that this rare complication present.