Implementation of a Systematic Tumor Screening Program for Lynch Syndrome in an Integrated Health Care Setting.

A subset of colorectal cancer (CRC) cases are attributable to Lynch syndrome (LS), a hereditary form of CRC. Effective evaluation for LS can be done on CRC tumors to guide diagnostic testing. Increased diagnosis of LS allows for surveillance and risk reduction, which can mitigate CRC-related burden and prevent cancer-related deaths. We evaluated participation in LS screening among newly diagnosed adult CRC patients. Some cases were referred for genetics evaluation prior to study recruitment (selective screening). Those not referred directly were randomized to the intervention or control (usual care) arms. Control cases were observed for one year, then given information about LS screening. Patients who declined participation were followed through the medical record. Of 601 cases of CRC, 194 (32%) enrolled in our study and were offered LS screening, 43 (7%) were followed as a control group, 148 (25%) declined participation and 216 (36%) were ineligible [63 (10%) of which received prior selective screening]. Six and nine cases of LS were identified through the intervention and selective screening groups, respectively. Overall, a higher proportion of PMS2 variants were identified in the intervention (3/6, 50%) versus selective screening groups (2/9, 22%) (not statistically significant). Eighty-eight percent and 23% of intervention and control patients, respectively, received LS screening. No control patients were found to have LS. Systems-based approaches are needed to ensure we fully identify LS cases. The proportion of LS cases from this program was 4% of newly diagnosed cases of CRC, similar to other programs.

Universal screening for Lynch syndrome among patients with colorectal cancer: patient perspectives on screening and sharing results with at-risk relatives.

Universal screening for Lynch syndrome (LS) among all cases of colorectal cancer (CRC) could increase the diagnosis of LS and reduce morbidity and mortality of LS-associated cancers. Given universal screening includes all patients, irrespective of high risk factors such early age at onset or family history of CRC, it is important to understand perspectives of all patients and not just those at high risk. As part of a study to assess the feasibility and implementation of universal screening, 189 patients newly diagnosed with CRC were surveyed about their interest in screening for LS and communication of results with at-risk family members. Overall, participants responded positively regarding screening for LS, with most wanting to know their genetic risks in general (86%) and risk of hereditary CRC (93%). Prior to receiving screening results, most participants stated they intended to share their screening results with parents (89%), siblings (96%), and children (96%). Of the 28 participants who received a positive LS screening result, 26 (93%) reported sharing their result with at least one first-degree family member. Interest in screening for LS and communication of screening results with family members was not associated with high risk factors. This study indicates that patients are interested in being screened for LS and that sharing information on the risk of LS with at-risk family members is not a significant barrier. These findings provide novel insight into patient perspectives about screening for LS and can guide successful implementation of universal screening programs.

Highly active antiretroviral therapy and human immunodeficiency virus encephalitis.

The ability of highly active antiretroviral therapy (HAART) to prevent the onset of HIV-associated dementia and to prevent or reduce the neuropathological features of HIV encephalitis (HIVE) remains unclear. Using a severe combined immunodeficient (SCID) mouse model of HIVE, we determined the effects of regular HAART treatment on HIVE. Before studying HAART in infected SCID mice, nonmanipulated SCID mice were treated with a single injection of the HAART cocktail (consisting of zidovudine, lamivudine, and indinavir) to determine optimum dosage and sampling time and to measure antiretroviral levels in the brain. After these preliminary studies, SCID mice that were inoculated with either HIV-infected or uninfected human monocytes were given intraperitoneal (IP) injections of HAART three times daily over a 1- and 2-week period. All three drugs were detected in the brain using a novel drug extraction technique and a modified high-performance liquid chromatography method. HAART significantly decreased the amount of astrogliosis and viral load in treated mice compared with mice that received vehicle injections. These studies offer insight into the ability of HAART to treat HIV infection of the brain.

The severe combined immunodeficient (SCID) mouse model of human immunodeficiency virus encephalitis: deficits in cognitive function.

The severe combined immunodeficient (SCID) mouse model of human immunodeficiency virus (HIV) encephalitis exhibits many of the histopathological and pathophysiological features of human HIV-associated dementia (HAD). Although deficits that may resemble HAD in humans have been reported for HIV-infected SCID mice, the cognitive deficit aspect of the model has very limited empirical support. Here, the authors report that HIV-infected SCID mice display cognitive deficits on a task requiring the animal to learn and remember the spatial relationship of cues in its environment in order to locate a submerged platform in a Morris water maze. The cognitive deficits manifest as longer latencies to locate the platform on the last day of the maze acquisition period and during a retention test 8 days later. Control experiments indicated that the poor performance by HIV-infected mice in comparison to controls was not due to impaired motor function or swimming ability, impaired visual acuity, or increased susceptibility to fatigue. Thus, the increased times required for HIV-infected mice to locate the submerged platform during the acquisition and memory tests likely reflect a cognitive deficit, rather than sensorimotor or emotional abnormalities. These behavioral deficits are associated with significant increases in astrogliosis and microgliosis in the HIV-infected mice. The results of this study strengthen the SCID mouse model of HIV encephalitis by definitively establishing cognitive deficits for the model in addition to its previously reported neuropathological features.