The 11th edition of Harrison's Principles of Internal Medicine welcomes Anthony Fauci to its editorial staff, in addition to more than 85 new contributors. While the organization of the book is similar to previous editions, major emphasis has been placed on disorders that affect multiple organ systems. Important advances in genetics, immunology, and oncology are emphasized. Many chapters of the book have been rewritten and describe major advances in internal medicine. Subjects that received only a paragraph or two of attention in previous editions are now covered in entire chapters. Among the chapters that have been extensively revised are the chapters on infections in the compromised host, on skin rashes in infections, on many of the viral infections, including cytomegalovirus and Epstein-Barr virus, on sexually transmitted diseases, on diabetes mellitus, on disorders of bone and mineral metabolism, and on lymphadenopathy and splenomegaly. The major revisions in these chapters and many

Harrison's Principles of Internal Medicine

Cetuximab Monotherapy and Cetuximab plus Irinotecan in Irinotecan-Refractory Metastatic Colorectal Cancer

Excess body weight, as defined by the body mass index (BMI), has been associated with several diseases and includes subjects who are overweight (BMI≥25–29.9 kg/m2) or obese (BMI≥30 kg/m2). Overweight and obesity constitute the fifth leading risk for overall mortality, accounting for at least 2.8 million adult deaths each year. In addition around 11% of colorectal cancer (CRC) cases have been attributed to overweight and obesity in Europe. Epidemiological data suggest that obesity is associated with a 30–70% increased risk of colon cancer in men, whereas the association is less consistent in women. Similar trends exist for colorectal adenoma, although the risk appears lower. Visceral fat, or abdominal obesity, seems to be of greater concern than subcutaneous fat obesity, and any 1 kg/m2 increase in BMI confers additional risk (HR 1.03). Obesity might be associated with worse cancer outcomes, such as recurrence of the primary cancer or mortality. Several factors, including reduced sensitivity to antiangiogenic-therapeutic regimens, might explain these differences. Except for wound infection, obesity has no significant impact on surgical procedures. The underlying mechanisms linking obesity to CRC are still a matter of debate, but metabolic syndrome, insulin resistance and modifications in levels of adipocytokines seem to be of great importance. Other biological factors such as the gut microbita or bile acids are emerging. Many questions still remain unanswered: should preventive strategies specifically target obese patients? Is the risk of cancer great enough to propose prophylactic bariatric surgery in certain patients with obesity?

https://gut.bmj.com/content/gutjnl/62/6/933.full.pdf

Obesity and colorectal cancer

BACKGROUND & AIMS
A cascade of precursor lesions (eg, atrophic gastritis, intestinal metaplasia, and dysplasia) precedes most gastric adenocarcinomas. Quantification of gastric cancer risk in patients with premalignant gastric lesions is unclear, however. Consequently, endoscopic surveillance is controversial, especially in Western populations.


METHODS
To analyze current surveillance practice and gastric cancer risk in patients with premalignant gastric lesions, all patients with a first diagnosis between 1991 and 2004 were identified in the Dutch nationwide histopathology registry (PALGA); follow-up data were evaluated until December 2005.


RESULTS
In total, 22,365 (24%) patients were diagnosed with atrophic gastritis, 61,707 (67%) with intestinal metaplasia, 7616 (8%) with mild-to-moderate dysplasia, and 562 (0.6%) with severe dysplasia. Patients with a diagnosis of atrophic gastritis, intestinal metaplasia, or mild-to-moderate dysplasia received re-evaluation in 26%, 28%, and 38% of cases, respectively, compared with 61% after a diagnosis of severe dysplasia (P < .001). The annual incidence of gastric cancer was 0.1% for patients with atrophic gastritis, 0.25% for intestinal metaplasia, 0.6% for mild-to-moderate dysplasia, and 6% for severe dysplasia within 5 years after diagnosis. Risk factors for gastric cancer development were increasing severity of premalignant gastric lesions at initial diagnosis (eg, severe dysplasia, hazard ratio 40.14, 95% confidence interval 32.2-50.1), increased age (eg, 75-84 years, hazard ratio 3.75, 95% confidence interval 2.8-5.1), and male gender (hazard ratio 1.50, 95% CI 1.3-1.7).


CONCLUSIONS
Patients with premalignant gastric lesions are at considerable risk of gastric cancer. As current surveillance of these patients is inconsistent with their cancer risk, development of guidelines is indicated.

Gastric cancer risk in patients with premalignant gastric lesions

This review summarizes studies on the epidemiology and public health implications of Helicobacter pylori published in peer-reviewed journals from April 2010 through March 2011. Prevalence rates vary widely between different geographical regions and ethnic groups. An interesting study from the USA identified the degree of African ancestry as an independent predictor of H. pylori infection. Two studies have demonstrated early childhood as the period of transmission of infection and identified an infected sibling as an important risk factor. An oral–oral route of spread has been substantiated with several studies showing the presence of H. pylori in the oral cavity. Studies have shown the presence of H. pylori in drinking water and the role of poor living conditions and sanitation in H. pylori infection, supporting an oral–fecal route of spread. Screening for H. pylori as a gastric cancer pre-screening strategy has been described in Japan, and the importance of H. pylori eradication as a gastric cancer–prevention strategy has now been further emphasized in Japanese guidelines. Two studies have shown a decrease in the burden of dyspepsia and peptic ulcer disease with H. pylori eradication.

https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1523-5378.2011.00874.x

Epidemiology of Helicobacter Pylori Infection and Public Health Implications

Background
The outcomes of colorectal cancer are determined by host factors, including systemic inflammation. The purpose of this study was to evaluate the prognostic significance of fibrinogen and inflammation-based scores, as markers of the inflammatory response, in colon cancer.

Preoperative Plasma Hyperfibrinogenemia is Predictive of Poor Prognosis in Patients with Nonmetastatic Colon Cancer

Recently, some studies have shown that diabetes mellitus and metabolic syndrome increase the risk of colorectal neoplasms. Although the mechanism is not known, those have been proposed to contribute to this phenomenon, including insulin resistance, oxidative stress, and adipokine production. The objective of this study was to assess the association between metabolic risk factors and colorectal neoplasm. Study participants visited the National Cancer Center, Korea, for screening (2007–2009). A total of 1,771 diagnosed adenoma patients and 4,667 polyp-free controls were included. The association between risk factors and colorectal neoplasm was evaluated using logistic regression models. High waist circumference, blood pressure, and serum triglyceride levels were associated with an increased risk of colorectal adenoma. Metabolic syndrome (MS) was associated with an increased risk of adenoma (OR = 1.44, 95 % CI = 1.23–1.70). The association between MS and colorectal adenoma was observed regardless of advanced/low-risk adenoma, and multiplicity. MS affected right colon adenomas (OR = 1.50, 95 % CI = 1.22–1.85), left colon adenomas (OR = 1.36, 95 % CI = 1.05–1.76), and adenomas in multiple anatomical locations (OR = 1.59, 95 % CI = 1.19–2.12), but was not associated with rectum. Central obesity, triglyceride level, and MS are risk factors for colorectal adenoma including advanced adenoma and multiplicity.

Association of colorectal adenoma with components of metabolic syndrome

Abdominal Visceral Adipose Tissue Predicts Risk of Colorectal Adenoma in Both Sexes

Although small rectal carcinoid tumors can be treated using local excision, complete resection can be difficult because tumors are located in the submucosal layer. We evaluate the factors associated with pathologically complete local resection of rectal carcinoid tumors. Data were analyzed of 161 patients with 166 rectal carcinoid tumors who underwent local excision with curative intent from January 2001 to December 2010. A pathologically complete resection (P-CR) was defined as an en bloc resection with tumor-free lateral and deep margins. The study classified treatments into three categories for analysis: conventional polypectomy (including strip biopsy, snare polypectomy, and hot biopsy), advanced endoscopic techniques (including endoscopic mucosal resection with cap and endoscopic submucosal dissection), and surgical local excision (including transanal excision and transanal endoscopic microsurgery). We evaluated the P-CR rate according to treatment method, tumor size, initial endoscopic impression and the use of endoscopic ultrasound (EUS) or transrectal ultrasound (TRUS). The mean tumor size was 5.51 ± 2.43 mm (range 2–18 mm) and all lesions were confined to the submucosal layer. The P-CR rates were 30.9, 72.0, and 81.8 % for conventional polypectomy, advanced endoscopic techniques, and surgical local excision, respectively. Univariate analysis showed that P-CR was associated with treatment method, use of EUS or TRUS, and initial endoscopic impression. Multivariate analysis showed that only treatment method was associated with P-CR. Pathologically complete resection of small rectal carcinoid tumors was more likely to be achieved when using advanced endoscopic techniques or surgical local excision rather than conventional polypectomy.

Byung Chang Kim

Papers

Preoperative Plasma Hyperfibrinogenemia is Predictive of Poor Prognosis in Patients with Nonmetastatic Colon Cancer

Association of colorectal adenoma with components of metabolic syndrome

Abdominal Visceral Adipose Tissue Predicts Risk of Colorectal Adenoma in Both Sexes

Factors associated with complete local excision of small rectal carcinoid tumor.

Effect of Helicobacter pylori Infection and Its Eradication on Reflux Esophagitis and Reflux Symptoms