Colitis ulcerosa complicated by malignant lymphoma: case report and analysis of published works

Diffuse Involvement of Primary Colorectal Lymphoma Simulating Ulcerative Colitis

Diffuse involvement of colorectal lymphoma masquerading as colitis is a very rare presentation of primary colorectal lymphoma. Detecting occult lymphoma is difficult in the setting of diffuse colonic involvement with no definite mass and inflammatory mucosal changes. We encountered a case of diffuse-type primary colorectal lymphoma simulating ulcerative colitis in a previously healthy 31-year-old woman. Despite multiple mucosal biopsies, the biopsy diagnosis was not made due to unawareness of atypical lymphocytes admixed with dense lymphoplasmacytic infiltration. The present case emphasizes the importance of being aware of this rare presentation of primary colorectal lymphoma in order to avoid misdiagnosis.

Extranodal marginal zone B-cell lymphoma of Mucosa-Associated Lymphoid Tissue (MALT lymphoma) in ulcerative colitis

Extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) occurring in inflammatory bowel diseases, including ulcerative colitis (UC) and Crohn's disease, has been reported, although it is extremely rare. An 18-year-old man with a two-years history of UC underwent colon endoscopy, and was found to have active total UC ranging from anus to cecum. Six biopsies were obtained. The microscopic examinations showed severe infiltrations of atypical small lymphocytes. They showed hyperchromatic nuclei and increased nucleocytoplasmic ratio and scattered immunoblastic cells. Centrocyte-like atypical lymphocytes, monocytoid cells, and plasma cells were seen in some places. Vague germinal centers were present, and apparent lymphoepithelial lesions were seen. No crypt abscesses were seen, and there were few neutrophils. No apparent other findings of UC were seen. Immunohistochemically, the atypical lymphocytes were positive for vimentin, CD45, CD20, CD79α, CD138, κ-chain, λ-chain, and p53 and Ki-67 antigen (labeling index = 63%). They were also positive for CD45RO, CD3, and CD15, but these positive cells were very scant compared with CD20 and CD79α. They were negative for CD10, CD30, CD56, cytokeratin (CK) AE1/3, CK CAM5.2, CK34BE12, CK5, CK6, CK7, CK8, CK14, CK18, CK19, CK20, EMA, chromogranin, synaptophysin, NSE, S100 protein, CEA, CA19-9, p63, and HMB45. Without clinical information, the appearances are those of MALT lymphoma. However, with clinical information, making the diagnosis of MALT lymphoma was hesitated. It is only mentioned herein that atypical lymphocytic infiltrations indistinguishable from MALT lymphoma occurred in an 18-year-old male patient with a two-year history of UC.

Primary colorectal lymphoma-clinical outcomes in a population-based series

PURPOSE

The purpose of this study was to investigate the characteristics and the outcomes of primary colorectal lymphomas using a population-based registry.

METHODS

All cases of colorectal lymphoma diagnosed between 1980 and 2007 were identified using a provincial cancer registry. Patients meeting Dawson's criteria and having a negative bone marrow biopsy were included.

RESULTS

One hundred ten cases of colorectal lymphoma were identified, 43 met the inclusion criteria. The majority of patients was male (86%), and the median age at diagnosis was 62 (range 26-82) years. Tumors were mostly located in the cecum (51.1%) and rectum (20.9%). The 5-year overall survival rate calculated by the Kaplan-Meier method was 57%. Age under 60 was associated with a better median survival time (265 vs 54 months; p < 0.0001). The surgical treatment was associated with a better overall survival compared to medical treatment alone (110 vs 56 months; p = 0.083). Tumors located in the rectum were associated with a decreased overall survival (41 months vs 110 months; p = 0.065).

CONCLUSIONS

Primary colorectal lymphoma is a rare disease. The age at diagnosis is an important predictor of outcome. Surgical resection may be associated with improved survival. Rectal lymphoma appears to be associated with a worse outcome and may warrant more aggressive therapy.

Concomitant adenocarcinoma and colonic non-Hodgkin's lymphoma in a patient with ulcerative colitis: a case report and molecular analysis

Ulcerative colitis (UC) complicated by colonic lymphoma is rare, although UC is often accompanied by adenocarcinoma of the colon. A concurrent existence of adenocarcinoma and lymphoma in a patient with UC is extremely rare, and has not yet been analyzed at the molecular level. We report a 64-year-old female patient with concomitant adenocarcinoma and diffuse large B-cell lymphoma (DLBCL) in the colon of UC. The genetic changes in these two neoplasms were analyzed. The colon adenocarcinomas had a mutation in MSH6 gene, DNA methylation in CDKN2A gene, and increased microsatellite instability (MSI), although these genetic changes were not recognized in either DLBCL or non-neoplastic UC mucosa. The DLBCL was diagnosed as primary colonic lymphoma, and confirmed Epstein-Barr virus (EBV) infection. The adenocarcinomas and the non-neoplastic UC mucosa were EBV-negative. Our case presented here clearly shows that the development of adenocarcinoma and lymphoma in the colon with UC was caused by individual mechanisms.

Mechanisms of intestinal inflammation and development of associated cancers: lessons learned from mouse models

Chronic inflammation is strongly associated with approximately 1/5th of all human cancers. Arising from combinations of factors such as environmental exposures, diet, inherited gene polymorphisms, infections, or from dysfunctions of the immune response, chronic inflammation begins as an attempt of the body to remove injurious stimuli; however, over time, this results in continuous tissue destruction and promotion and maintenance of carcinogenesis. Here we focus on intestinal inflammation and its associated cancers, a group of diseases on the rise and affecting millions of people worldwide. Intestinal inflammation can be widely grouped into inflammatory bowel diseases (ulcerative colitis and Crohn's disease) and celiac disease. Long-standing intestinal inflammation is associated with colorectal cancer and small-bowel adenocarcinoma, as well as extraintestinal manifestations, including lymphomas and autoimmune diseases. This article highlights potential mechanisms of pathogenesis in inflammatory bowel diseases and celiac disease, as well as those involved in the progression to associated cancers, most of which have been identified from studies utilizing mouse models of intestinal inflammation. Mouse models of intestinal inflammation can be widely grouped into chemically induced models; genetic models, which make up the bulk of the studied models; adoptive transfer models; and spontaneous models. Studies in these models have lead to the understanding that persistent antigen exposure in the intestinal lumen, in combination with loss of epithelial barrier function, and dysfunction and dysregulation of the innate and adaptive immune responses lead to chronic intestinal inflammation. Transcriptional changes in this environment leading to cell survival, hyperplasia, promotion of angiogenesis, persistent DNA damage, or insufficient repair of DNA damage due to an excess of proinflammatory mediators are then thought to lead to sustained malignant transformation. With regards to extraintestinal manifestations such as lymphoma, however, more suitable models are required to further investigate the complex and heterogeneous mechanisms that may be at play.

Complete remission of a primary rectal lymphoma on ulcerative colitis, after withdrawal of azathioprine and infliximab

A 45-year-old woman was diagnosed with ulcerative colitis and treated with mesalazine, prednisone and, finally, azathioprine and infliximab. Colonoscopy revealed a rectal ulcer, identified by biopsy as a large cell B-lymphoma, positive for leukocyte common antigen (LCA), CD 20 and LMP-1 and negative for CD 3. Three months after withdrawal of all immunosuppressors, a proctocolectomy was performed. The resection specimen contained an area of B-cell polymorphic hyperplasia, but no residual tumour. The patient remains well after 2 years of follow-up, without any further antineoplastic therapy.

Primary colorectal lymphomas

OBJECTIVE

The incidence of primary colorectal lymphomas is rare, comprising 10-20% of gastrointestinal lymphomas and only 0.2-0.6% of large bowel malignancies. There is a male predominance, with a maximal reported incidence in the 50- to 70-year age group. Patients often present delayed with nonspecific symptoms and consequently have advanced disease at the time of diagnosis. Inflammatory bowel disease and immunosuppression have been reported as risk factors, although a direct causal link has yet to be established. Treatment often involves a multimodality approach, combining surgery and chemotherapy, with the use of radiotherapy in selected cases. We present our experience in the management of primary colorectal lymphomas over a 10-year period (1989-1999).

PATIENTS AND METHODS

We reviewed all cases of primary colorectal lymphoma seen at our institution from 1989 to 1999. Patients were included based on standard diagnostic criteria for primary intestinal lymphoma established by Dawson in 1961. The following clinical information was obtained: age, sex, presentation, site of tumour, operation performed, histology, length of stay, intraoperative complications, adjuvant therapy and duration of follow-up. The type of lymphoma was classified according to the WHO classification system. For staging, a modification of the Ann Arbor system for gastrointestinal lymphoma, proposed by Musshoff, was used.

RESULTS

During the 10-year period from 1989 to 1999, 14 cases of primary colorectal lymphomas were identified. This comprised 0.44% of all colorectal malignancies (14 of 3199 cases) seen in our department during this period. There were 13 men and one woman. Their mean age at presentation was 61 years. The common presentations included a combination of abdominal pain (71.4%), anorexia and loss of weight (42.9%) and an abdominal mass (28.6%). The two most common sites of involvement were the caecum (57.1%) and the rectum/sigmoid colon (21.4%). The lesions manifested in a variety of ways, ranging from solitary fungating masses to multiple colonic polyps. All but one patient underwent attempted curative surgical resection. All cases were non-Hodgkin's B-cell lymphomas, with a majority being diffuse large B-cell lymphomas (57.1%). The diagnoses were established through laparotomy in all cases. All cases presented with evidence of spread to regional lymph nodes or beyond. Eleven patients (78.6%) received postoperative chemotherapy, with a regimen that included cyclophosphamide, vincristine, doxorubicin and prednisone. The remaining three were too ill or refused. There were no mortalities within 30 days of surgery. The patients were followed up for a median of 20 months (range 2-84) and more than half are alive and continue to be on follow-up with no evidence of recurrence.

CONCLUSION

Primary colorectal lymphoma is a rare condition. It predominantly affects males between the sixth and seventh decade of life and most commonly occurs in the caecum. It often presents with abdominal pain and loss of weight and due to the nonspecific nature of these symptoms, patients frequently present late with advanced loco-regional disease. The histology is usually B cell and of intermediate grade. Therapy usually involves resection of the affected colon and regional lymphovascular structures, followed by adjuvant chemotherapy, with a reported 5-year survival of 27-55%.

Epstein-Barr virus infection in colorectal neoplasms associated with inflammatory bowel disease: detection of the virus in lymphomas but not in adenocarcinomas

Epstein-Barr virus (EBV) is associated with several lymphoid and epithelial human malignancies. The latter include gastric adenocarcinomas, while sporadic colorectal adenocarcinomas (CRCs) have been reported to be EBV-negative. Recently, increased numbers of EBV-infected B lymphocytes have been detected in intestinal mucosal samples affected by ulcerative colitis (UC) and, to a lesser extent, Crohn's disease (CD). Both CRC and colorectal non-Hodgkin's lymphoma (NHL) are recognized complications of inflammatory bowel disease (IBD), but it is unclear to what extent EBV contributes to the development of these neoplasms. Seventeen cases of IBD-associated CRC and nine cases of IBD-associated colorectal NHL were therefore studied for the presence of EBV by in situ hybridization. EBV-positive cases were further studied for the expression of the EBV-encoded nuclear antigen (EBNA) 2 and the latent membrane protein (LMP) 1 of EBV by immunohistochemistry. Four out of seven cases of colorectal NHL associated with UC were shown to be EBV-positive. In addition, two of two colorectal NHLs developing in patients with CD were EBV-positive. Of the EBV-positive lymphomas, three displayed a pattern of EBV latent gene expression consistent with type I latency (EBNA2(-)/LMP1(-)), two a type II pattern (EBNA2(-)/LMP1(+)), and one a type III pattern (EBNA2(+)/LMP1(+)). These findings suggest that EBV infection is involved in the pathogenesis of a proportion of colorectal NHLs developing in IBD. Iatrogenic immunosuppression may contribute to the development of these lymphomas. By contrast, all 17 IBD-associated CRCs were EBV-negative, including a case of CRC occurring synchronously with an EBV-positive NHL. In conjunction with previous reports on sporadic CRCs, this suggests that EBV is not involved in the pathogenesis of CRC.

Primary intestinal lymphoma complicating Crohn's disease

A 32-year-old man with a 12-year history of Crohn's disease of the colon was found to have a 5-cm cecal mass on colonoscopy. Histology examination of the lesion revealed high-grade B-cell lymphoma of Burkitt's type. He was treated with chemotherapy and has done well in the past 12 months. Review of the literature reveals 30 cases of lymphoma in patients with a history of Crohn's disease.

Malignancies in inflammatory bowel disease: fact or fiction?

BACKGROUND

The association between ulcerative colitis (UC), Crohn disease (CD) and colorectal cancer (CRC) has been confirmed in several studies. The aim of this study was critical analysis of the relation between IBD and malignancy.

METHODS

Review of the literature.

RESULTS

In UC, the extent of the disease, its duration and start at a young age are risk factors for the development of CRC. Primary sclerosing cholangitis and colonic strictures are additional risk factors for development of CRC. The relation between azathioprine or 6-MP and the development of lymphomas is a subject of debate. The administration of anti-TNF-alpha has produced some concern about the development of lymphomas in CD. However, at present there is no evidence of lymphomas caused by anti-TNF-alpha in CD. On the contrary, some drugs seem to have a preventive effect on CRC development in UC. 5-aminosalicylic acid in particular and to a lesser extent sulphasalazine have prevented the development of CRC significantly in retrospective studies. In CD, there is no strong relationship between the disease and the development of CRC or other malignancies. Only the development of small-bowel carcinoma is reported with a much higher frequency.

CONCLUSIONS

There is a correlation with UC and the development of CRC. For CD, this correlation is less firmly established. There is a possible, but not proven, relation between AZA/6-MP use and the development of lymphoma in IBD. There is also a probable relationship between CD and the development of small-bowel carcinoma. In some retrospective studies, the use of 5-aminosalicylic or sulphasalazine has been shown to prevent the development of CRC in UC.

Survival and causes of death in Italian patients with ulcerative colitis. A GISC nationwide study

BACKGROUND

Death rate for patients with ulcerative colitis has changed over last few decades. Recent studies indicate that cumulative long-term mortality is comparable to that in general population, and that deaths may depend on causes not strictly related to colonic disease.

AIM

To evaluate overall and cause-specific mortality rate in a large group of Italian patients with ulcerative colitis.

METHODS

A total of 2,066 ulcerative colitis patients aged >18 years consecutively diagnosed in twenty Italian Gastroenterology Units between 1964 and 1995 were followed-up from diagnosis until 1997. Standardised Mortality Ratios and Relative Survival Ratios were calculated.

RESULTS

Overall mortality of patients with ulcerative colitis was comparable to that in general population with 93 deaths observed versus 92.1 expected (standardises mortality ratio, 1.0; 95% confidence interval, 0.8-1.2). Significantly higher mortality was observed in patients under 30 years of age at diagnosis (standardised mortality ratio, 2.7; 95% confidence interval, 1.3-4.9), and in those diagnosed before 1974 (standardised mortality ratio, 2.7; 95% confidence interval, 1.1-5.7). Proctocolitis and complications from surgery were mentioned in 11 and 5 certificates, respectively. A significant excess of deaths was observed for colorectal cancer (colon: standardised mortality ratio, 3.0; 95% confidence interval, 1.0-6.9; rectum: standardised mortality ratio, 4.4; 95% confidence interval, 1.2-11.3), and haemolymphopoietic neoplasms (standardised mortality ratio, 2.8; 95% confidence interval, 1.0-6.1), in particular multiple myeloma and non-Hodgkin lymphoma. A significant deficit of deaths was observed for cancer of the respiratory system (standardised mortality ratio, 0.3; 95% confidence interval, 0.1-1.0).

CONCLUSIONS

This study confirms that, also in Italy, mortality of patients with ulcerative colitis is comparable to that in general population. Only 12% of deaths were due to ulcerative colitis itself, whereas 10% of deaths were attributed to colorectal cancer. Deaths from colorectal cancer occurred, on average, 9 years after diagnosis of ulcerative colitis, suggesting that the risk of cancer is not limited to patients with long-standing colitis. As to mortality for causes unrelated to colitis, there was an excess of deaths due to malignancies of the haemolymphopoietic system.

Colorectal neoplasia in ulcerative colitis-recent advances

It is recognized that ulcerative colitis (UC) predisposes to the development of colorectal adenocarcinoma (CRC), and the molecular pathway for this process differs from that for sporadic CRCs. However, several important details regarding the risk factors for and the molecular changes underlying UC-related colorectal carcinogenesis have only come to light lately. First, recent data suggest environmental factors related to long-standing inflammation contribute more to this increased cancer risk than an inherited susceptibility. Second, molecular changes that may represent the first steps in the development of neoplasia are being increasingly identified in non-dysplastic, colitic mucosa. Third, there is now good evidence suggesting that UC-related CRC may develop along more than one molecular pathway. These emerging data will hopefully contribute to attempts to prevent the development of UC-related CRC, e.g. through refining surveillance programmes. Details of the molecular heterogeneity of UC-related dysplasia and CRC may also help develop reliable tools for diagnosing the former and for predicting the behaviour of the latter. Finally, there is increasing awareness of non-epithelial colorectal malignancies which are associated with UC and may potentially increase in incidence with changes in the medical management of this inflammatory disease.

Rectal lymphoma in ulcerative colitis treated with azathioprine

Primary malignant lymphoma of the bowel is a rare complication of inflammatory bowel disease. The association of gastrointestinal lymphoma, inflammatory bowel disease and prior immunosuppression remains unclear. We report the first case of azathioprine-treated ulcerative colitis developing rectal lymphoma.

Ulcerative Colitis and Colonic Lymphoma: A Theoretical Link

Ulcerative colitis (UC) is an inflammatory disease of the colon and rectum. Although colonic adenocarcinoma is a recognized complication of UC there have been few reported cases of gastrointestinal lymphoma arising in this setting. We describe our experience with such a case and review the literature that attempts to explain possible genetic etiologies for the malignant transformation of gastrointestinal lymphoid tissue to lymphoma as well as a link between UC and lymphoma.

Gastrointestinal lymphoma: prevention and treatment of early lesions

Gastrointestinal lymphomas comprise a group of distinct clinicopathological entities. Differences in lifestyle and environmental factors between countries could account for the variety in the distribution of the main subtypes: low-grade B-cell lymphomas of the mucosa-associated lymphoid tissue type, alpha-chain disease and enteropathy (coeliac disease)-associated T-cell lymphoma (EATL). The possibility of preventing these lymphomas implies a knowledge of their natural history together with an identification of potential predisposing factors. The development of the lymphoid hyperplasia and subsequently low-grade lymphoma with the possibility of high-grade transformation is a multifactorial process involving both antigenic and host-related factors. The pathogenic role of Helicobacter pylori and gluten has been demonstrated in gastric lymphoma and enteropathy-associated T-cell lymphoma respectively, while environmental factors, especially non-specific bacterial ones, may play a major role in the pathogenesis of alpha-chain disease. The most difficult task in preventing these lymphomas is the recognition of early lesions likely to regress after the removal of the exogenous stimulus.

Increased incidence of non-Hodgkin's lymphoma in inflammatory bowel disease patients on immunosuppressive therapy but overall risk is low

BACKGROUND

There is concern that the incidence of non-Hodgkin's lymphoma (NHL) will rise with increasing use of immunosuppressive therapy.

AIMS

Our aim was to determine the risk of NHL in a large cohort of patients with inflammatory bowel disease (IBD), and to study the association between IBD, NHL, and immunosuppressive therapy.

METHODS

We studied 782 IBD patients (238 of whom received immunosuppressive therapy) who attended our medical centre between 1990 and 1999 (median follow up 8.0 years). Standardised incidence ratios (SIRs) and 95% confidence intervals (CI) were calculated. Expected cases were derived from 1995 age and sex specific incidence rates recorded by the National Cancer Registry of Ireland.

RESULTS

There were four cases of NHL in our IBD cohort (SIR 31.2; 95% CI 2.0-85; p=0.0001), all of whom had received immunosuppressive therapy: azathioprine (n=2), methotrexate (n=1), and methotrexate and cyclosporin (n=1). Our immunosuppressive group had a significantly (59 times) higher risk of NHL compared with that expected in the general population (p=0.0001). Three cases were intestinal NHL and one was mesenteric. Mean age at NHL diagnosis was 49 years, mean duration of IBD at the time of NHL diagnosis was 3.1 years, and mean duration between initiation of immunosuppressive therapy and diagnosis of NHL was 20 months.

CONCLUSIONS

Although underlying IBD may be a causal factor in the development of intestinal NHL, our experience suggests that immunosuppressive drugs can significantly increase the risk of NHL in IBD. This must be weighed against the improved quality of life and clinical benefit immunosuppressive therapy provides for IBD patients.

Lymphoma arising in an S-pouch after total proctocolectomy for ulcerative colitis: report of a case

The gastrointestinal tract is the most common extranodal site of primary non-Hodgkin's lymphoma. We present a case of a 50-year-old male with primary B cell lymphoma arising in an S-pouch eight years after a total proctocolectomy for ulcerative colitis. After chemoradiotherapy the patient remained asymptomatic, with an intact S-pouch. Pouch conservation is feasible in patients with primary lymphoma of the pouch, using chemoradiotherapy and close follow-up examinations.

Epstein-Barr virus-positive primary gastrointestinal Hodgkin's disease: association with inflammatory bowel disease and immunosuppression

Inflammatory bowel disease (IBD) is associated with an increased risk of lymphoma, which is usually extraintestinal but sometimes may involve the diseased bowel itself. Most lymphomas described in this setting are of non-Hodgkin's type, but rare cases of Hodgkin's disease (HD) have been reported. We describe the clinicopathologic and molecular features of four patients with primary gastrointestinal HD. Three patients had preexistent Crohn's disease (CD), for which two of them had received immunosuppressive therapy. The fourth patient had a longstanding history of diverticulitis and myasthenia gravis and was receiving immunosuppressive therapy for the latter. Multifocal involvement of the bowel by HD was noted in all four cases. Disease was staged as IVA in one patient, IIIB in one patient, and IE in one patient, and the fourth patient died in the postoperative period before further workup. Two patients received chemotherapy, one of whom was dead at 9 months, whereas the other has no evidence of disease at 25 months' follow-up. The patient with IE disease did not receive any therapy because only a few microscopic foci of disease were present and is also without any evidence of disease at 17 months. The Reed-Sternberg (RS) cells in all four cases expressed CD30, CD15, EBER-1, and LMP-1; two of four were focally CD20-positive. VJ-polymerase chain reaction for immunoglobulin heavy chain (IgH) rearrangement showed a polyclonal pattern in all four cases. In two cases, laser capture microdissection was used to isolate individual RS and Hodgkin's cells, which contained rearranged immunoglobulin genes, confirming a B-cell genotype. Whereas one case showed a dominant clonal band present in all isolates, cells from the patient with stage IE disease clearly showed a polyclonal population of RS cells. Our findings indicate that HD arising in the setting of IBD or chronic inflammation is the result of an Epstein-Barr virus-driven lymphoproliferation, analogous to that found in other immunodeficient states. Disordered immunoregulation inherent to CD and immunosuppressive therapy for the latter may contribute to its development. The finding of polyclonal RS cells in a patient with early stage disease and apparent cure by surgical resection versus monoclonal RS cells in the patient with disseminated disease suggests that HD in the setting of immunodeficiency also may show molecular progression, in a manner similar to that occurring in conventional B-cell lymphoproliferative disorders arising in the same setting.

Primary T-cell lymphoma of the colon

A 40-year-old woman had been diagnosed with Crohns disease in September 1994, but later examinations revealed a primary T-cell lymphoma of the colon. Colonoscopic and histological examination showed ulcerative lesions simulating Crohns disease involving the entire colon and the terminal ileum, and she was first diagnosed as having Crohns disease. Differential therapeutic strategies, including corticosteroid, had improved the symptoms which were dominated by abdominal pain. When she visited our institute in April 1995, she presented with bloody stool twice a day, 7 kg weight loss in a period of six months and a slightly painful abdomen. Colonoscopic finding showed geographic ulceration on the entire colon, especially rectum and terminal ileum. The histologic examination of specimens from colonoscopic biopsy showed primary peripheral T-cell lymphoma of the colon. Any dense lymphocyte infiltrates seen in the biopsy specimens obtained from lesions simulating ulcerative colitis or Crohns disease should be assessed to exclude intestinal lymphoma.

Large intestinal lymphocytic phlebitis and venulitis in chronic ulcerative colitis

Colonic vasculitis is seen in Crohn's disease and as a component of primary systemic vasculitis. It has rarely been described in chronic ulcerative colitis. Here we report a case of ulcerative colitis with prominent transmural lymphocytic phlebitis and venulitis. Although this is, to our knowledge, the first description of such an association, its recognition is important if confusion with other entities is to be avoided. The etiology of the vascular changes is unclear but they may be a secondary phenomenon induced by antigens, toxins or cytokines draining from the inflamed mucosa.