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Dive into the research topics where James Alan Kemp is active.

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Featured researches published by James Alan Kemp.


Annals of Internal Medicine | 1998

Is Colonoscopy Indicated for Small Adenomas Found by Screening Flexible Sigmoidoscopy

Michael B. Wallace; James Alan Kemp; Yvona M. Trnka; Joanne M. Donovan; Francis A. Farraye

Several studies have shown that screening for colorectal cancer by fecal occult blood testing and lower endoscopy with removal of polyps reduces the mortality rate associated with colorectal cancer [1-3]. One recommended method of screening low-risk patients for colorectal cancer is the use of flexible sigmoidoscopy to detect neoplastic (adenomatous or cancerous) polyps. Many health organizations recommend that asymptomatic persons older than 50 years of age be screened for colorectal cancer with fecal occult blood testing and flexible sigmoidoscopy. This practice has become standard at many centers in the United States [4-7]. Flexible sigmoidoscopy is simple to perform, is well tolerated by patients, and is less expensive than colonoscopy. Other studies have shown that patients with adenomatous polyps in the distal colon are at increased risk for adenomatous polyps in the proximal colon [8-10]. Thus, it is accepted practice to recommend a full colonoscopy with examination of the proximal colon for all patients with adenomas in the distal colon. Studies comparing the natural history of small and large colonic adenomas have suggested that small (<1 cm) polyps have a lower risk for subsequent malignant transformation than do larger polyps [11, 12]. Other studies support the observation that small polyps are unlikely to be malignant or to have high-grade histologic features [13]. As data have accumulated on screening low-risk patients with flexible sigmoidoscopy, some investigators have noted a low prevalence (0.0% to 0.8%) of histologically advanced polyps in the proximal colon among patients with small distal tubular adenomas [9, 14]. Two other retrospective studies [15, 16] suggested that the long-term risk for colon cancer in the proximal colon among patients with small polyps in the distal colon is low. Other investigators [17] reported higher rates of advanced polyps in the proximal colon among patients with small distal adenomas, but this study included patients who had small tubular and villous adenomas on flexible sigmoidoscopy. Thus, estimates of the prevalence of advanced proximal polyps among patients with small adenomas detected by flexible sigmoidoscopy currently conflict. We sought to determine the prevalence of advanced adenomatous polyps in the proximal colon among patients with small tubular adenomas found on flexible sigmoidoscopy. We used a large prospective cohort of average-risk patients undergoing screening for colorectal cancer. Methods Patients Data were collected prospectively on flexible sigmoidoscopic examinations performed in 4490 patients as part of a colon cancer screening program at a large urban Veterans Affairs medical center and a health maintenance organization from 1992 to 1996. Baseline variables were collected on a standardized data form and included family history of colorectal cancer in first- and second-degree relatives, age at diagnosis, history of blood in the stool, and previous endoscopy. Flexible sigmoidoscopy was offered to patients referred by a primary care provider for colorectal cancer screening who were asymptomatic, were older than 50 years of age, did not have a first-degree relative 55 years of age or younger with colon cancer, had a negative result on a fecal occult blood test, and had not had previous barium enema or colonoscopy. Patients were prepared for screening by administration of two phosphosoda enemas on the morning of the examination. Examinations were performed by a trained physician assistant, nurse practitioner, or gastroenterology fellow under the supervision of a staff gastroenterologist. An endoscope was inserted to a depth of 60 cm or until solid stool was encountered. All polyps smaller than 10 mm identified by flexible sigmoidoscopy were biopsied and examined histologically. Patients with polyps larger than 10 mm on flexible sigmoidoscopy either underwent biopsy or were referred directly for colonoscopy (during which the polyp was removed). Polyps were characterized as non-neoplastic (normal mucosa, hyperplastic, or inflammatory) or neoplastic (tubular adenoma, tubulovillous adenoma, villous adenoma, high-grade dysplasia, or adenocarcinoma) by a gastrointestinal pathologist. The size of the polyp was estimated to the nearest millimeter by using an open biopsy forceps placed in direct contact with the polyp before polyp removal. All patients with neoplastic polyps were offered colonoscopy. Patients with single small adenomas (1 to 5 mm) were advised of the controversy over the implications of a single small distal adenoma found on flexible sigmoidoscopy. Colonoscopy was performed within 6 months of flexible sigmoidoscopy. Patients were prepared for colonoscopy by administration of polyethylene glycol-electrolyte gastrointestinal lavage or oral phosphosoda. All colonoscopies were performed by staff gastroenterologists or gastroenterology fellows under the supervision of a staff gastroenterologist. If a polyp was encountered, its location was estimated according to the distance from the anal verge as measured with markings on the endoscope. Polyp size was estimated to the nearest millimeter according to the methods described above. All visualized polyps were removed and characterized histologically. Polyps were considered advanced if they were larger than 10 mm or were characterized as tubulovillous, villous, high-grade dysplasia, or adenocarcinoma. Patients were prospectively subgrouped according to the number (1 or >1), size (1 to 5 mm, 6 to 10 mm, or >10 mm), and histologic characteristics (nonadvanced or advanced) of distal neoplastic polyps. Proximal neoplastic polyps were defined as those that were identified by colonoscopy (but not flexible sigmoidoscopy) and were proximal to the sigmoid-descending colon junction. Statistical Analysis The prevalence of advanced proximal polyps was determined, and subgroup analysis was performed on the basis of the size and number of neoplastic polyps found in the distal colon by flexible sigmoidoscopy. Confidence intervals for the prevalence rates were calculated by using exact methods for binomial data [18]. A chi-square test for linear trend was used to determine whether the three categories of distal polyps (single 1 to 5 mm, multiple or 6 to 10 mm, or advanced) showed an increasing association with advanced proximal polyps. Logistic regression analysis was performed by using S-Plus software (Statistical Sciences, Inc., Seattle, Washington) to evaluate for confounding by age and sex. Differences between patients with a distal neoplastic polyp who did or did not undergo colonoscopy were compared by using the Student t-test for continuous variables and the z-test for categorical variables. All tests were two-sided. The costs and consequences of the screening evaluation were determined by creating a decision model in DATA Software (TreeAge Inc., Williamstown, Massachusetts). Cost data for colonoscopy, biopsy, polypectomy, and flexible sigmoidoscopy were obtained from the Agency for Health Care Policy and Research publication on colorectal cancer screening [6]. The likelihood of having a polyp was taken directly from the observed data in the study. An estimate of the prevalence of proximal polyps among patients with no distal adenomas was obtained from the study by Rex and colleagues [19]. To include the observed data and 95% CIs, sensitivity analysis was performed on the prevalence of advanced proximal polyps among patients with tubular adenomas 1 to 5 mm in diameter on flexible sigmoidoscopy. Role of Funding Source The Harvard Pilgrim Health Care Foundation, the source of funding for this study, did not participate in data collection, analysis, or publication of this study. Results A neoplastic polyp was detected in 401 of 4490 asymptomatic patients who underwent flexible sigmoidoscopy, did not have first-degree relatives younger than 55 years of age with colorectal cancer, and had a negative result on a fecal occult blood test. Data on the size, location, and histologic characteristics of all polyps was complete for 392 patients (98%). Nine patients were excluded because of incomplete data (polyp was resected but not recovered for pathologic analysis [n = 6]) or polyp size was not reported [n = 3]). The mean age (SD) of patients with neoplasia was 62.5 8.1 years; 71% were male, and 29% were female. The histologic characteristics and size of the most advanced neoplastic polyps detected by flexible sigmoidoscopy among patients who had subsequent complete colonic visualization is shown in Table 1. Table 1. Histology and Size of Distal Polyps Detected on Flexible Sigmoidoscopy All 392 patients with distal neoplastic polyps were offered colonoscopy, and 301 (77%) agreed to undergo the procedure. All of the 91 patients who did not undergo colonoscopy had tubular adenomas. Eighty-six patients had a single adenoma 1 to 5 mm in diameter, 2 had multiple adenomas 1 to 5 mm in diameter, 2 had a single adenoma 6 to 10 mm in diameter, and 1 had multiple adenomas 6 to 10 mm in diameter. No patient with advanced distal adenomas refused colonoscopy. To look for potential bias between patients who did or did not undergo colonoscopy for a tubular adenoma 1 to 5 mm in diameter found by flexible sigmoidoscopy, we compared the mean age, presence of a family history of colorectal cancer other than in a first-degree relative younger than 55 years of age, and the site at which flexible sigmoidoscopy was performed (Veterans Affairs medical center or health maintenance organization). Patients who did and patients who did not undergo colonoscopy for a tubular adenoma 1 to 5 mm in diameter did not differ for age or family history of colorectal cancer (data not shown). Acceptance of a recommendation for colonoscopy differed significantly by the site at which flexible sigmoidoscopy was done. Among patients with distal adenomas, the Veterans Affairs medical center completed colonoscopy in 56 of 58 patients (96.6%) and the health


The American Journal of Medicine | 1999

Screening for colorectal cancer with flexible sigmoidoscopy by nonphysician endoscopists.

Michael B. Wallace; James Alan Kemp; Frank Meyer; Kimberly Horton; Angela Reffel; Cindy L. Christiansen; Francis A. Farraye

PURPOSE Screening with sigmoidoscopy reduces the risk of death from colorectal cancer. Only 30% of eligible patients have undergone sigmoidoscopy, in part because of a limited supply of endoscopists. We evaluated the performance and safety of screening sigmoidoscopic examinations by trained nonphysician endoscopists in comparison with board-certified gastroenterologists. SUBJECTS AND METHODS Asymptomatic patients 50 years or older without evidence of fecal occult blood and no personal history or family history of a first-degree relative with colorectal cancer under age 55 years were offered sigmoidoscopy. All examinations were performed either by a gastroenterologist or a trained nonphysician endoscopist at a staff model health maintenance organization. Outcomes included the depth of examination, number and histology of polyps, and complications. RESULTS Nonphysicians performed 2,323 sigmoidoscopic examinations, and physicians performed 1,378 examinations. The mean (+/-SD) depth of sigmoidoscopy examinations performed by nonphysicians was 52 +/- 10 cm compared with 55 +/- 9 cm (P <0.001) in physicians. Nonphysicians detected neoplastic polyps in a greater proportion of patients (7.8%) than physicians (5.8%), but this difference was not significant after adjusting for differences in the age, sex, and family history of the patients (P = 0.35). No major complications occurred. The cost per examination, including the nonphysician training cost, was lower for nonphysicians (


The American Journal of Gastroenterology | 2003

Chronic acid-related disorders are common and underinvestigated

Sumit R. Majumdar; Stephen B. Soumerai; Francis A. Farraye; Marianne Lee; James Alan Kemp; James M. Henning; Peggy Schrammel; Robert F. LeCates; Dennis Ross-Degnan

186 per examination) than for physicians (


Alimentary Pharmacology & Therapeutics | 2005

Controlled trial of interventions to increase testing and treatment for Helicobacter pylori and reduce medication use in patients with chronic acid‐related symptoms

Sumit R. Majumdar; Dennis Ross-Degnan; Francis A. Farraye; Marianne Lee; James Alan Kemp; Robert F. LeCates; James M. Henning; S. R. Tunis; P. Schrammel; Stephen B. Soumerai

283 per examination). CONCLUSIONS Appropriately trained nonphysicians may be capable of performing safe and effective screening for colorectal cancer with flexible sigmoidoscopy. An increased use of nonphysicians to perform sigmoidoscopy may increase the availability and reduce the cost of the procedure.


Digestive Diseases and Sciences | 1997

Case Report: Diffuse Mesenteric Amyloidosis

V. Mohan; James Alan Kemp; Howard E. LeWine; Michael Rabin; Meryl L. Goldstein; Francis A. Farraye

OBJECTIVES:The aims of this study were as follows: to establish the prevalence of chronic acid-related disorders in a managed care population; to describe these patients; and to examine rates of adherence to current guidelines for investigation of dyspepsia and peptic ulcer disease.METHODS:The design was a population-based cohort study. The sample was drawn from 216,720 adult (aged >18 yr) members of a managed care organization that had an electronic medical record linked to administrative and pharmacy databases. We included adults with continuous enrollment from July, 1998, to January, 2000, who were dispensed histamine-2 blockers or proton-pump inhibitors, or both, for ≥1 yr. Dispensing data, sociodemographic and clinical information, comorbidities, and investigations were collected and analyzed.RESULTS:The final cohort consisted of 5064 patients; 64% were aged ≥50 yr, 47% were male, and 11% were African American. The prevalence of chronic acid-related disorders was 2.3%. Gastroesophageal reflux disease (59%) was the most common condition, followed by dyspepsia (35% of cohort; 18% investigated by endoscopy). There were 917 dyspepsia patients ≥50 yr who had not been investigated by endoscopy (81% of dyspepsia patients in this age group). There were 97 patients with peptic ulcer disease who did not have a documented test for Helicobacter pylori (34% of patients with peptic ulcer disease).CONCLUSIONS:Chronic acid-related disorders are common in primary care, and many patients use acid suppressing medications on a long-term basis. Nevertheless, according to current practice guidelines, our patients were underinvestigated. Future guidelines should specifically address the management of patients who use acid suppressing medications on a chronic basis.


JAMA Internal Medicine | 1999

A randomized controlled trial of an enhanced patient compliance program for Helicobacter pylori therapy.

Marianne Lee; James Alan Kemp; Adrianne Canning; Christine Egan; Gary Tataronis; Francis A. Farraye

Background : Many symptomatic patients take proton pump inhibitors or histamine‐2 blockers for years and those without gastro‐oesophageal reflux disease might benefit from Helicobacter pylori eradication.


Journal of General Internal Medicine | 2007

Screening Patients with a Family History of Colorectal Cancer

Robert H. Fletcher; Rebecca Lobb; Mark R. Bauer; James Alan Kemp; Richard C. Palmer; Ken Kleinman; Irina Miroshnik; Karen M. Emmons

A 54-year-old man was admitted to the hospital with eight months of abdominal and back pain, early satiety, dyspnea, lightheadedness, and new onset constipation. The past medical history was remarkable for hypertension, hypercholesterolemia, and diabetes mellitus. Medicines on admission included lovastatin, lisinopril, glyburide, aspirin, and metoprolol. The family history was noncontributory. Physical exam revealed normal vital signs, bibasilar rales, diffuse abdominal tenderness without peritoneal signs, a suggestion of a ̄ uid wave, normal rectal exam, guaiacnegative stool, and bilateral leg edema to the knees. Laboratory ® ndings included a hematocrit of 34%, white blood count of 12,300/mm 3 with a mild left shift, glucose 302 mg/dl (70 ± 112), ALT 49 units/liter (5± 35), AST 32 units/liter (22± 47), alkaline phosphatase 182 units/liter (36 ± 118), normal electrolytes, amylase, and lipase. Urinalysis revealed 1 1 protein, glucose, and ketones with rare WBCs, RBCs, and hyaline casts. ECG was normal. Chest x-ray showed an enlarged cardiac silhouette, vascular redistribution, and a small right pleural effusion consistent with congestive heart failure. The ̄ atplate of the abdomen showed a large amount of stool throughout the colon. Computed tomography of the abdomen revealed a 43 4-cm mass in the region of the root of the mesentery, with changes consistent with in ̄ ammation in the surrounding mesenteric fat and ascites in the right perihepatic and pericolic spaces (Figure 1). Paracentesis revealed bloody ̄ uid. An abdominal angiogram was unremarkable. Exploratory laparotomy was undertaken with a preoperative diagnosis of intraabdominal malignancy. Induration of the base of the mesentery was noted without a distinct mass. Multiple enlarged lymph nodes were present in the mesentery surrounding the celiac trunk and the superior mesenteric artery. Biopsy of the base of the mesentery and lymph nodes revealed extensive fat necrosis with amorphous eosinophilic material replacing much of the normal lymph node architecture. There was no evidence of malignancy or other intraabdominal abnormalities. Congo red stain and birefrigence studies led to a ® nal diagnosis of amyloidosis. Immunoperoxidase studies showed no staining of amyloid with antibodies to either kappa or lambda light chains on either paraf® n-embedded or frozen material. However, congophilia was resistant to permanganate pretreatment, as is seen typically with primary (AL) amyloidosis. Serum protein electrophoresis and immunoelectrophoresis revealed hypogammaglobulinemia without a monoclonal spike. Urine protein determination and immunoelectrophoresis detected 171 mg protein/24 hr without Bence Jones protein. Bone marrow biopsy showed no evidence for myeloma, granuloma, or infectious organism. Plasma cells and plasmacytoid lymphocytes were increased, representing 10% of nucleated cells. He was treated with colchicine, prednisone, and melphalan but developed progressive amyloidosis with severe cardiomyopathy, hepatosplenomegaly, ascites, and peripheral neuropathy. Echocardiography revealed massive concentric left and right ventricular hypertrophy with mild tricuspid regurgitation. All four valves had thickening of the lea ̄ ets. He died in congestive heart failure 10 months after his initial diagnosis and 18 months after he developed abdominal pain. Autopsy ® ndings revealed severe amyloid deposition enlarging and virtually replacing both spleen (330 g) and lymph nodes in the mesentery and retroperitoneum (Figure 2). Immunoperoxidase stains for kappa and lambda light chains on paraf® n-embedded material were nonconclusive. Diffuse, extensive interstitial deposition of amyloid was associated with enlargement of the heart (650 g) and liver (1850 g). No evidence of amyloid vasculopathy was found in the brain. All sections of the gastrointestinal tract had patches of amyloid involvement, which was heavier in the stomach and small bowel than in the large bowel and esophagus. Amyloid deposition tended to be localized beManuscript received July 26, 1994; revised manuscript received September 12, 1996; accepted January 22, 1997. From the Departments of Medicine and Anatomical Pathology, Brigham and Womens Hospital and Harvard Medical School, Boston, Massachusetts; Lyons VA Medical Center, Lyons, New Jersey; and Harvard Pilgrim Health Care, Boston, Massachuset ts. Address for reprint requests: Dr. Francis A. Farraye, Harvard Pilgrim Health Care, 291 Independence Drive, West Roxbury, Massachuset ts 02167. Digestive Diseases and Sciences, Vol. 42, No. 5 (May 1997), pp. 1079 ± 1082


Digestive Diseases and Sciences | 1997

Diffuse mesenteric amyloidosis.

Mohan; James Alan Kemp; Howard E. LeWine; Rabin M; Goldstein Ml; Francis A. Farraye


JAMA Internal Medicine | 1957

Amelioration of diabetes mellitus due to pituitary necrosis.

James Alan Kemp


Annals of Internal Medicine | 1999

Colonoscopy for Small Adenomas

Michael B. Wallace; Francis A. Farraye; James Alan Kemp

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Michael B. Wallace

Brigham and Women's Hospital

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James M. Henning

TAP Pharmaceutical Products

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