Environmental health sciences and the community.

Environmental health science investigators train for many years to acquire the in-depth knowledge and expertise critical to successful research. The inherent components of hypothesis generation, study design, methodology, analysis, and interpretation of research which are central to the investigative process take years of dedicated work to develop. Moreover, the very aim of research—getting at the truth—requires an unbiased and impartial approach to answering the questions asked. However, scientists can’t always do patient-oriented research on their own, which is why the community is such an important component of our success at the NIEHS. Community partners can identify environmental exposures that are of concern, encourage the public to participate in research, help to set research priorities, and provide the bridge to developing and implementing effective interventions to reduce exposures and prevent disease. 
 
The NIEHS and the broader community have had a distinguished and productive relationship. Under former director Ken Olden’s leadership, the NIEHS pioneered programs in community-based participatory research, health disparities, and environmental justice. Many research programs including the Core Centers, the Superfund Basic Research Program, the Centers for Children’s Environmental Health and Disease Prevention Research, the Breast Cancer and the Environment Research Centers, and the Centers for Population Health and Health Disparities each have active, vibrant community-based research or outreach activities that complement and extend the fundamental basic and disease-oriented research supported by the institute. The NIEHS has engaged the public by involving communities affected by environmental hazards in their neighborhoods in the research process. These programs have provided an ideal opportunity for communities to actively partner with scientists to engage in environmental health research, while also identifying the NIEHS as a leader and innovator in this novel approach to patient-oriented research. 
 
The NIEHS has created direct channels of communication by holding regular Town Meetings throughout the United States, and by developing the Public Interest Liaison Group (PILG), made up of representatives of community, disease-advocacy, and environmental organizations, that meets regularly with the NIEHS leadership. The NIEHS also took the lead in establishing an Interagency Working Group on Community-Based Participatory Research involving a number of NIH institutes, the Environmental Protection Agency, the Department of Housing and Urban Development, and the Department of Transportation. 
 
Some successful outcomes of the NIEHS and community partnerships include: 
 
 
public housing regulations to account for issues related to lead and allergen exposure; 
 
 
working with managed healthcare insurers to include asthma education services through home health aids to reduce reliance on hospital facilities in managing asthma symptoms among urban low-income, minority children; 
 
 
increased understanding and awareness of environmental triggers of asthma in schools and implementation of new cleaning protocols to reduce exposures; 
 
 
mobilization of local residents to raise concerns about pollution that resulted in citation of polluters in neighborhoods with high exposures; 
 
 
involvement of community advisory boards in planning and implementing family intervention studies to reduce asthma triggers and pesticide residue exposures to protect children’s health; and 
 
 
involvement of breast cancer survivor advocates as participants and key partners in facilitating the translation of research findings on the effects of early exposures on mammary gland development. 
 
 
 
Strong partnerships between researchers and community members will remain critical to the success of the NIEHS in fulfilling our mission of understanding disease and improving public health. 
 
While the institute’s community-based activities continue to change and evolve, the commitment that the NIEHS has to community-based research remains strong. As we prioritize areas for growth and development, the needs and health of communities are a specific focus of our vision. Our programs in integrative research, global environmental health, and exposure biology all focus on problems that evolve from and are relevant to the community. In addition, as part of our response to Hurricane Katrina, the NIEHS will develop a community-responsive research program to investigate the potential health effects of mold and microbial contamination of the home and work environment. Recognizing the importance of community input, we have also invited a PILG representative to regularly attend the NIEHS Advisory Council meetings. 
 
As we move forward, community-based research programs will be integrated into the overall direction and goals of the NIEHS. We will stand by our prior commitments and ensure that we actively listen to our community stakeholders, involve them in critical research, and look to them for meaningful interventions. Strong partnerships between researchers and community members will remain critical to the success of the NIEHS in fulfilling our mission of understanding disease and improving human health.


Background
Meckel's diverticulum, the most commonly encountered congenital anomaly of the small intestine, affects 2% of the population [1,2]. The vast majority of Meckel's diverticulae are incidentally discovered during autopsy, laparotomy, or barium studies [3]. Meckel's diverticulum is surgically removed only when a complication arises or a neoplasia develops. The tumors are infrequent and observed only in 0.5-3.2% of the Meckel's diverticula. Of these, 12% tumors are GIST. We are reporting one such incidence, where we came across a Meckel's diverticulum harboring GIST.

Case presentation
Sixty-five year old gentle man presented with constipation for 4 months and bleeding per rectum for one month.
Physical examination was unremarkable. Ultrasonography of the abdomen revealed 6 × 9 cms exophytic hypoechoic lesion in pelvis near sigmoid colon. Barium enema study was normal. Colonoscopy showed colitis from anal canal up to 20 cms. Rest of Colon was normal up to Caecum. Contrast enhanced computerized tomography (CT) scan showed lobulated mass lesion in pelvis posteriosuperior to the urinary bladder compressing anterior wall of sigmoid colon. CT scan picture was suggestive of soft tissue tumour in close relation to sigmoid colon or sigmoid mesentery (figure 1), a diagnosis of small bowel tumor compressing sigmoid colon was made. An exploratory laparotomy was done. On laparotomy, the lobulated tumour seems to be arising from an ileal diverticulum, which was very short in length and situated 50 cms from ileocaecal valve. So diagnosis was soft tissue tumour aris-ing from Meckel's diverticulum. The tumour was adherent to sigmoid colon and part of wall of urinary bladder (figure 2, 3). There was no evidence of distant spread. Tumour was excised with 3 cm of ileum on either side. End to end anastomosis was done in two layers. Involved area of anterior wall of sigmoid colon was also excised and the defect was closed transversally. Adherent part of the urinary bladder musculature was resected but the bladder mucosa was intact. Postoperative period was uneventful. Postoperatively urinary catheter was retained for 10 days.
The pathology report was gastrointestinal stromal tumour (GIST) arising from Meckel's diverticulum. The tumour cells were pleomorphic and 2-3 mitosis were present in 50 high power fields (figure 4). All margins were negative. Immuno-hisochemistry showed positive reaction for vimentin and C kit ( Figure 5). But desmin, actin, S100, and CD 34 were negative.

Discussion
Meckel's diverticulum is the most commonly encountered congenital anomaly of the small intestine, occurring in approximately 2% of the population [1,2]. Meckel's diverticulum is located on the antimesentric border of the ileum approximately 45 to 60 cm proximal to the ileocecal valve and results from incomplete closure of the omphalomesentric, or viteline duct. An equal incidence is found among men and women. Heterotopic mucosa is present in Meckel's diverticulum, the most common of which is gastric mucosa (present in 50% of all Meckel's diverticula). Pancreatic mucosa is encountered in approximately 5% of diverticula. Similarly these diverticula may habour colonic mucosa. intestinal obstruction, and diverticulitis. Incidence of tumours within the Meckel's diverticulm is 0.5 to 3.2% [4][5][6]. Most of them are commonly benign tumours like leiomyomas, angiomas, and lipomas. Malignant neoplasms include adenocarcinoma (which commonly originate from the gastric mucosa), sarcoma, carcinoid tumour and GIST.
GISTs are rare neoplasms which account for 0.1-1% of gastrointestinal malignancies. The term itself was first used in 1983 by Mazur and Clark [7] to identify a heterogeneous group of tumours, all of them histologically characterized by hyperplastic fused cells, not necessarily leiomuscular ones, but even neural ones. Gastrointestinal stromal tumours arise from the interstitial cells of Cajal, pace maker cells of Gastrointestinal tract [8].
For many patients, the detection of GIST may be an incidental finding during evaluation of nonspecific symptoms. Symptoms tend to arise only when tumours reach a large size or are in critical anatomic location. Most symptomatic patients present with tumours larger than 5 cm in maximal dimension. Symptoms at presentation may include abdominal pain, abdominal mass, nausea, vomiting, anorexia, and weight loss. The vast majority of meta-Intraoperative picture showing tumour arising from Meckel's diverticulum; Tumour was located in Meckel's diverticulum and adherent to wall of urinary bladder Figure 2 Intraoperative picture showing tumour arising from Meckel's diverticulum; Tumour was located in Meckel's diverticulum and adherent to wall of urinary bladder.
static GISTs are located intraabdominal, either in the liver, in the omentum, or in the peritoneal cavity [9]. Metastatic spread to lymph nodes and to other regions via lymphatics is very rare.
CT is usually an adequate technology to diagnose tumours arising from Meckel's diverticulum as long as appropriate techniques for both noncontrast and intravenous contrast administrations are used [13]. Histopathologically, disease exhibits a wide variety of appearances with characteristics of either epitheloid (approximately 70%) or spindle cell histology (remaining 30%). Nor-mally, the KIT protein serves as a transmembrane RTK; the CD117 antigen can be detected by immunohistochemical staining as marker for the presence of the KIT protein.
With the use of sophiscated technology, it has become clear that KIT mutations can be noted in more than 90% of GIST cells.
CD34 expression is not specific for GIST, because it can also be noted in desmoid tumours, and approximately 60% to 70% of GIST lesions are positive for CD34 [17][18][19]. Expert analysis of the KIT and PDGFRA genotype may be useful to define with certainty the group of rare patients with CD117-negative GISTs in the future. GIST is considered to be potentially malignant tumours. [19].
Most reliable prognostic factors are the size of the primary tumour and the mitotic index which measure proliferative activity of the cells. Other prognostic factors are specific histologic subtypes (epitheloid vs. spindle cell), the degree of cellular pleomorphism and age of the patient. Recurrence and survival rates have also been reported to correlate with the location of the primary GIST lesion, with small bowel tumours showing a somewhat worse prognosis. The functional imaging in GISTs with FDG-PET can give additional information that can assist clinicians in the management of patients. Definitive surgery remains the mainstay of treatment for patients with localized, primary GIST.
Histopathology slide after Immunostaining for C-Kit; Tumour cells show positivity after C-Kit staining, which suggests GIST Figure 5 Histopathology slide after Immunostaining for C-Kit; Tumour cells show positivity after C-Kit staining, which suggests GIST.
Intraoperative picture showing tumour and Meckel's divertic-ulum; Picture of Meckel's diverticulum with part of tumour, which was delivered out Figure 3 Intraoperative picture showing tumour and Meckel's diverticulum; Picture of Meckel's diverticulum with part of tumour, which was delivered out.
High power view of the histopathology slide; Tumour cells were pleomorphic and 2-3 mitosis were present in 50 high power fields Figure 4 High power view of the histopathology slide; Tumour cells were pleomorphic and 2-3 mitosis were present in 50 high power fields.