Management of adverse events from the treatment of encorafenib plus cetuximab for patients with BRAF V600E-mutant metastatic colorectal cancer: insights from the BEACON CRC study

Colorectal cancer is the second leading cause of cancer deaths worldwide, with a 5-year relative survival of 14% in patients with metastatic colorectal cancer (mCRC). Patients with BRAF V600E mutations, which occur in ∼10%-15% of patients with mCRC, have a poorer prognosis compared with those with wild-type BRAF tumours. The combination of the BRAF inhibitor encorafenib with the epidermal growth factor receptor inhibitor cetuximab currently represents the only chemotherapy-free targeted therapy approved in the USA and Europe for previously treated patients with BRAF V600E-mutated mCRC. As a class, BRAF inhibitors are associated with dermatologic, gastrointestinal, and renal events, as well as pyrexia and secondary skin malignancies. Adverse event (AE) profiles of specific BRAF inhibitors vary, however, and are affected by the specific agents given in combination. In patients with mCRC, commonly reported AEs of cetuximab monotherapy include infusion reactions and dermatologic toxicities. Data from the phase III BEACON CRC study indicate that the combination of encorafenib with cetuximab has a distinct safety profile. Here we review the most frequently reported AEs that occurred with this combination in BEACON CRC and best practices for managing and mitigating AEs that require more than standard supportive care.

Restricted dispersal in a sea of gene flow

How far do marine larvae disperse in the ocean? Decades of population genetic studies have revealed generally low levels of genetic structure at large spatial scales (hundreds of kilometres). Yet this result, typically based on discrete sampling designs, does not necessarily imply extensive dispersal. Here, we adopt a continuous sampling strategy along 950 km of coast in the northwestern Mediterranean Sea to address this question in four species. In line with expectations, we observe weak genetic structure at a large spatial scale. Nevertheless, our continuous sampling strategy uncovers a pattern of isolation by distance at small spatial scales (few tens of kilometres) in two species. Individual-based simulations indicate that this signal is an expected signature of restricted dispersal. At the other extreme of the connectivity spectrum, two pairs of individuals that are closely related genetically were found more than 290 km apart, indicating long-distance dispersal. Such a combination of restricted dispersal with rare long-distance dispersal events is supported by a high-resolution biophysical model of larval dispersal in the study area, and we posit that it may be common in marine species. Our results bridge population genetic studies with direct dispersal studies and have implications for the design of marine reserve networks.

PCR-RFLP analyses of Leishmania species causing cutaneous and mucocutaneous leishmaniasis revealed distribution of genetically complex strains with hybrid and mito-nuclear discordance in Ecuador

PCR-Restriction Fragment Length Polymorphism (RFLP) analyses targeting multiple nuclear genes were established for the simple and practical identification of Leishmania species without using expensive equipment. This method was applied to 92 clinical samples collected at 33 sites in 14 provinces of Ecuador, which have been identified at the species level by the kinetoplast cytochrome b (cyt b) gene sequence analysis, and the results obtained by the two analyses were compared. Although most results corresponded between the two analyses, PCR-RFLP analyses revealed distribution of hybrid strains between Leishmania (Viannia) guyanensis and L. (V.) braziliensis and between L. (V.) guyanensis and L. (V.) panamensis, of which the latter was firstly identified in Ecuador. Moreover, unexpected parasite strains having the kinetoplast cyt b gene of L. (V.) braziliensis and nuclear genes of L. (V.) guyanensis, L. (V.) panamensis, or a hybrid between L. (V.) guyanensis and L. (V.) panamensis were identified. This is the first report of the distribution of a protozoan parasite having mismatches between kinetoplast and nuclear genes, known as mito-nuclear discordance. The result demonstrated that genetically complex Leishmania strains are present in Ecuador. Since genetic exchanges such as hybrid formation were suggested to cause higher pathogenicity in Leishmania and may be transmitted by more species of sand flies, further country-wide epidemiological studies on clinical symptoms, as well as transmissible vectors, will be necessary.

Leishmaniasis caused by intracellular protozoa of the genus Leishmania is a neglected tropical disease widely distributing worldwide, especially in tropical and subtropical areas. Approximately 20 species are known to be pathogenic to humans, of which eight species have been recorded as causative agents of cutaneous and mucocutaneous leishmaniases in Ecuador. Since infecting species are the major determinant of clinical outcomes, identification at the species level is important for the treatment and prognosis. The parasite species have been identified conventionally by multilocus enzyme electrophoresis (MLEE) and recently by genetic analysis such as sequencing and genotyping. In the present study, PCR-Restriction Fragment Length Polymorphism (RFLP) targeting multiple nuclear genes was employed, and the results were compared with those obtained by kinetoplast cytochrome b (cyt b) gene sequence analysis, which is widely applied to species identification. Although most results corresponded between the two analyses, PCR-RFLP revealed presence of unexpected genetically complex Leishmania strains having characteristics of hybrid and mito-nuclear discordance. Since hybrid strains of Leishmania were suggested to increase disease severity and may be transmitted by a wider range of sand fly species, careful epidemiological research, including clinical courses and vector research, will be needed.

Geographic Distribution of Leishmania Species in Ecuador Based on the Cytochrome B Gene Sequence Analysis

A countrywide epidemiological study was performed to elucidate the current geographic distribution of causative species of cutaneous leishmaniasis (CL) in Ecuador by using FTA card-spotted samples and smear slides as DNA sources. Putative Leishmania in 165 samples collected from patients with CL in 16 provinces of Ecuador were examined at the species level based on the cytochrome b gene sequence analysis. Of these, 125 samples were successfully identified as Leishmania (Viannia) guyanensis, L. (V.) braziliensis, L. (V.) naiffi, L. (V.) lainsoni, and L. (Leishmania) mexicana. Two dominant species, L. (V.) guyanensis and L. (V.) braziliensis, were widely distributed in Pacific coast subtropical and Amazonian tropical areas, respectively. Recently reported L. (V.) naiffi and L. (V.) lainsoni were identified in Amazonian areas, and L. (L.) mexicana was identified in an Andean highland area. Importantly, the present study demonstrated that cases of L. (V.) braziliensis infection are increasing in Pacific coast areas.

Genotyping of sand fly species in Peruvian Andes where leishmaniasis is endemic

Genotyping of sand fly species circulating in Peru was established on the basis of PCR-restriction fragment length polymorphisms (RFLPs) of the 18S ribosomal RNA (rRNA) gene. The sequences of 18S rRNA gene fragments from 12 Lutzomyia and 1 Warileya species were determined and their RFLP-patterns were analyzed. Consequently, RFLP analysis with the restriction enzyme AfaI and then HapII or KpnI, followed by XspI successfully differentiated them. Intraspecific genetic diversity affecting RFLP-patterns was not detected in the specimens collected from 24 areas of 8 departments. The genotyping was applied to the surveillance of sand flies collected from Andean areas where leishmaniasis is endemic, and its usability was verified. The present method promises to be a powerful tool for the classification and surveillance of sand flies circulating in Peru.

Natural infections of man-biting sand flies by Leishmania and Trypanosoma species in the northern Peruvian Andes

The natural infection of sand flies by Leishmania species was studied in the Andean areas of Peru where cutaneous leishmaniasis caused by Leishmania (Viannia) peruviana is endemic. Sand flies were captured by human bait and Center for Disease Control (CDC) light trap catches at Nambuque and Padregual, Department of La Libertad, Peru, and morphologically identified. Among 377 female sand flies dissected, the two dominant man-biting species were Lutzomyia (Helcocyrtomyia) peruensis (211 flies) and Lutzomyia (Helcocyrtomyia) caballeroi (151 flies). Another sand fly species captured by light trap was Warileya phlebotomanica (15 flies). The natural infection of sand flies by flagellates was detected in 1.4% of Lu. (H.) peruensis and 2.6% of Lu. (H.) caballeroi, and the parasite species were identified as Le. (V.) peruviana and Trypanosoma avium, respectively, by molecular biological methods. The results indicated that the vector species responsible for the transmission of leishmaniasis in the study areas is Lu. (H.) peruensis. In addition, the presence of Trypanosoma in man-biting sand fly species means that more careful consideration is necessary for vector research in areas of Andean Peru where leishmaniasis is endemic.

Improving oral hygiene for the seriously ill patient: implementing research-based practice

A research-based policy and procedure to improve the oral hygiene care of intubated and other seriously ill patients was developed, implemented, and evaluated. The project resulted in (a) improved oral hygiene for patients, (b) standardization and simplification of nursing practice, and (c) a reduction in supply costs. The project has implications for nursing practice and evidence-based practice protocol development.

Characteristics related to poor glycemic control in NIDDM patients in community practice

OBJECTIVE

To identify clinical characteristics related to poor glycemic control in patients with NIDDM cared for by Michigan primary care physicians.

RESEARCH DESIGN AND METHODS

This study was a cross-sectional secondary analysis of data from 393 NIDDM patients (mean age, 63 +/- 11 years; 54% female; 92% white) in the 1990-1991 Michigan Diabetes in Communities II Study. We evaluated patient demographic, clinical, and physiological characteristics, attitudes toward diabetes, and self-care ability. Logistic regression was used for multivariate evaluation of the characteristics of those patients whose glycosylated hemoglobin (normal GHb 4-8%) was in the upper 25% of the study sample (GHb > 11.6%).

RESULTS

A high meal-stimulated plasma C-peptide was associated with a lower likelihood of poor control (odds ratio [OR] for highest quartile vs. all others = 0.37; 95% CI 0.23-0.58). Longer time since diagnosis (OR for each 5 years duration = 1.28; 95% CI 1.07-1.53), poor self-care ability (OR = 1.85; 95% CI 1.27-2.71), and perceived absence of dietary recommendations (OR = 2.37; 95% CI 1.11-5.08) were also independently associated with presence in the highest GHb quartile. Characteristics that were not significantly related to poor glycemic control included sex, age, obesity, educational level, exercise, self-rated health status, and pharmacological treatment.

CONCLUSIONS

1) Poor glycemic control may reflect progressive failure of islet function, although the independent relationships of C-peptide level and time since diagnosis are consistent with concepts of heterogeneous mechanisms underlying NIDDM. 2) Despite the important relationships of biological characteristics of NIDDM to glycemic control, patient attitudes and self-care ability may be useful targets for designing management strategies for certain poorly controlled patients.

Estimating cancer screening indicators in the primary care setting

The software "Profile: A Cancer Risk Profile of Your Patient Practice" was used to estimate cancer screening activities in a primary care practice. "Profile" is a public health tool that does not track the screening histories of individual patients, but rather, using a sampling strategy, provides estimates for the entire practice of the age and sex specific number of screening eligible patients, the number screened, and the number that should have been screened, based on National Cancer Institute/American Cancer Society (NCI/A CS) guidelines. This report describes "Profile," and the results it generated from a sample of medical records. Primary care providers who seek to integrate primary and secondary cancer prevention activities into their routine practices will find it useful to have an objective estimate of their current level of such activities.