BACKGROUND

Nonpolypoid (flat and depressed) colorectal lesions are increasingly recognized. Their endoscopic removal requires specialized EMR techniques, which are more complex to perform. Outcomes data on EMR of nonpolypoid neoplasms in the United States is needed.

OBJECTIVE

To determine the safety and efficacy of EMR in the resection of nonpolypoid colorectal neoplasms > or = 1 cm.

DESIGN

Retrospective analysis.

SETTING

Veterans Affairs Palo Alto Health Care System.

PATIENTS

Over a 5-year period, patients who underwent EMR for nonpolypoid colorectal lesions > or = 1 cm.

INTERVENTION

A standardized approach that included lesion assessment, classification, inject-and-cut EMR technique, reassessment, and treatment of residual tissue.

MAIN OUTCOME MEASUREMENTS

Complete resection, bleeding, perforation, development of advanced cancer, and death.

RESULTS

A total of 100 patients (125 lesions: 117 flat and 8 depressed) met inclusion criteria. Mean size was 16.7 +/- 7 mm (range, 10-50 mm). Histology included 5 submucosal invasive cancers, 5 carcinomas in situ, and 91 adenomas. Thirty-eight patients (48 lesions) did not receive surveillance colonoscopy: 8 had surgery, 16 had hyperplastic pathology, and 14 did not undergo repeat examination. Surveillance colonoscopy was performed on 62 patients (77 lesions). Complete resection was achieved in 100% of these patients after 1 to 3 surveillance colonoscopies. All patients received follow-up (mean [standard deviation] = 4.5 +/- 1.4 years); none developed colorectal cancer or metastasis.

LIMITATIONS

Single endoscopist, retrospective study.

CONCLUSIONS

A standardized EMR (inject-and-cut) technique is a safe and curative treatment option in nonpolypoid colorectal neoplasms (> or = 1 cm) in the United States.

Matrix metalloproteinases (MMPs) are central to the development and progression of dysfunctional ventricular remodeling after tissue injury. We studied 6 month old heterozygous mice with cardiac-specific transgenic expression of active MMP-2 (MMP-2 Tg). MMP-2 Tg hearts showed no substantial gross alteration of cardiac phenotype compared to age-matched wild-type littermates. However, buffer perfused MMP-2 Tg hearts subjected to 30 min of global ischemia followed by 30 min of reperfusion had a larger infarct size and greater depression in contractile performance compared to wild-type hearts. Importantly, cardioprotection mediated by ischemic preconditioning (IPC) was completely abolished in MMP-2 Tg hearts, as shown by abnormalities in mitochondrial ultrastructure and impaired respiration, increased lipid peroxidation, cell necrosis and persistently reduced recovery of contractile performance during post-ischemic reperfusion. We conclude that MMP-2 functions not only as a proteolytic enzyme but also as a previously unrecognized active negative regulator of mitochondrial function during superimposed oxidative stress.

This study aimed to investigate whether HIV and HIV-related factors are associated with spontaneously resolved hepatitis C virus (HCV) infection and levels of hepatitis C viremia. Among 351 anti-HCV(+) injection drug users, with and without HIV infection, multivariate methods were used to evaluate whether HIV status and HIV viral load, CD4 T-cell count, and concurrent HIV antiretroviral therapy were associated with (1) spontaneously resolved HCV infection and (2) HCV RNA levels. In 186 HIV patients, decreased HCV resolution was independently associated with Black race and modestly associated with CD4 T-cell count <200 cells/ml. Among 310 patients with persistent HCV infection, higher HCV RNA levels were independently associated with HIV status but not with other HIV-related factors. HIV may be associated with persistent HCV infection in patients with low CD4 T-cell counts. Moreover, HIV is associated with increased HCV viral load, which may attenuate response to HCV antiviral treatment in coinfected patients.