Methyl α-D-galactopyranosyl-(1→3)-ß-D-galactopyranoside and methyl ß-D-galactopyranosyl-(1→3)-ß-D-galactopyranoside: Glycosidic linkage conformation determined from MA'AT analysis.

MA'AT analysis has been applied to two biologically-important O-glycosidic linkages in two disaccharides, α-D-Galp-(1→3)-ß-D-GalpOMe (3) and ß-D-Galp-(1→3)-ß-D-GalpOMe (4). Using density functional theory (DFT) to obtain parameterized equations relating a group of trans-O-glycosidic NMR spin-couplings to either phi (ϕ') or psi (ψ'), and experimental 3JCOCH, 2JCOC, and 3JCOCC spin-couplings measured in aqueous solution in 13C-labeled isotopomers, probability distributions of ϕ' and ψ' in each linkage were determined and compared to those determined by aqueous 1-µs molecular dynamics (MD) simulation. Good agreement was found between the MA'AT and single-state MD conformational models of these linkages for the most part, with modest (approximately <15°) differences in the mean values of ϕ' and ψ', although the envelope of allowed angles (encoded in circular standard deviations or CSDs) is consistently larger for ϕ' determined from MA'AT analysis than from MD for both linkages. The MA'AT model of the α-Galp-(1→3)-ß-Galp linkage agrees well with those determined previously using conventional NMR methods (3JCOCH values and/or 1H-1H NOEs), but some discrepancy was observed for the ß-Galp-(1→3)-ß-Galp linkage, which may arise from errors in the conventions used to describe the linkage torsion angles. Statistical analyses of X-ray crystal structures show ranges of ϕ' and ψ' for both linkages that include the mean angles determined from MA'AT analyses, although both angles adopt a wide range of values in the crystalline state, with ϕ' in ß-Galp-(1→3)-ß-Galp linkages showing greater-than-expected conformational variability.

Role of Surgery in Metastatic Melanoma and Review of Melanoma Molecular Characteristics.

We aimed to review the molecular characteristics of metastatic melanoma and the role of surgery in metastasectomy for metastatic melanoma. We performed a systematic literature search on PubMed to identify relevant studies focusing on several mutations, including NRAS, BRAF, NF1, MITF, PTEN, TP53, CDKN2A, TERT, TMB, EGFR, and c-KIT. This was performed in the context of metastatic melanoma and the role of metastasectomy in the metastatic melanoma population. A comprehensive review of these molecular characteristics is presented with a focus on their prognosis and role in surgical metastasectomy.

Risk of hepatitis B virus reactivation in cancer patients undergoing treatment with tyrosine kinase-inhibitors.

This editorial commented on an article in the World Journal of Gastroenterology titled "Risks of Reactivation of Hepatitis B Virus in Oncological Patients Using Tyrosine Kinase-Inhibitors: Case Report and Literature Analysis" by Colapietro et al. In this editorial, we focused on providing a more comprehensive exploration of hepatitis B virus reactivation (HBVr) associated with the usage of tyrosine kinase inhibitors (TKIs). It includes insights into the mechanisms underlying HBV reactivation, the temporal relationship between TKIs and HBV reactivation, and preventive measures. The aim is to understand the need for nucleos(t)ide analogs (NAT) and serial blood tests for early recognition of reactivation and acute liver injury, along with management strategies. TKIs are considered to be an intermediate (1%-10%) of HBVr. Current guidelines stipulate that patients receiving therapy with high or moderate risks of reactivation or recent cancer diagnosis must have at least tested hepatitis B surface antigen, anti-hepatitis B core antigen (HBc), and anti-hepatitis B surface antibody. Anti-HBc screening in highly endemic areas means people with negative tests should be vaccinated against HBV. Nucleoside or nucleotide analogs (NAs) like entecavir (ETV), tenofovir disoproxil fumarate (TDF), and tenofovir alafenamide (TAF) form the basis of HBV reactivation prophylaxis and treatment during immunosuppression. Conversely, lamivudine, telbivudine, and adefovir are generally discouraged due to their reduced antiviral efficacy and higher risk of fostering drug-resistant viral strains. However, these less effective NAs may still be utilized in cases where ETV, TDF, and TAF are not feasible treatment options.

Disparities in time to treatment initiation for rectal cancer patients: an analysis of demographic and socioeconomic factors.

Background: This study investigated demographic and socioeconomic factors contributing to disparities in the time to treatment for rectal cancer. Subgroup analysis based on age < 50 and ≥ 50 was performed to identify differences in time to treatment among young adults (age < 50) compared to older adults with rectal cancer. Methods: An analysis was performed using data from the National Cancer Database, spanning from 2004 to 2019. The study encompassed 281,849 patients diagnosed with rectal cancer. We compared time intervals from diagnosis to surgery, radiation, and chemotherapy, considering age, sex, race, and socioeconomic variables. Analyses were performed for the entire cohort and for two subgroups based on age (< 50 and ≥ 50). Results: Overall, Hispanic patients experienced longer times to surgery, radiation, and chemotherapy compared to non-Hispanic patients (surgery: 94.2 vs. 79.1 days, radiation: 65.0 vs. 55.6 days, chemotherapy: 56.4 vs. 47.8 days, all p < 0.001). Patients with private insurance had shorter times to any treatment (32.5 days) compared to those with government insurance or no insurance (30.6 and 32.5 days, respectively, p < 0.001). Black patients experienced longer wait times for both radiation (63.4 days) and chemotherapy (55.2 days) compared to White patients (54.9 days for radiation and 47.3 days for chemotherapy, both p < 0.001). Interestingly, patients treated at academic facilities had longer times to treatment in surgery, radiation, and chemotherapy compared to those treated at comprehensive and community facilities. When analyzed by age, many of the overall differences persisted despite the age stratification, suggesting that these disparities were driven more by demographic and socioeconomic variables rather than by age. Conclusion: Significant differences in the time to treatment for rectal cancer have been identified. Hispanic patients, individuals lacking private insurance, Black patients, and patients receiving care at academic facilities had the longest times to treatment. However, these differences were largely unaffected by the age (< 50 and ≥ 50) subgroup analysis. Further investigation into the causes of these disparities is warranted to develop effective strategies for reducing treatment gaps and enhancing overall care for rectal cancer patients.

Disparities in Time-to-treatment for Patients With Melanoma.

BACKGROUND/AIM: This study aimed to investigate the demographic and socioeconomic factors associated with disparities in the time-to-treatment for melanoma. PATIENTS AND METHODS: We conducted an analysis of patients with melanoma from 2004 to 2019 using the National Cancer Database. Time intervals from diagnosis to surgery, radiation, and chemotherapy were compared based on age, sex, race, and socioeconomic status. RESULTS: A total of 647,273 patients with melanoma were included. Overall, Hispanic patients had the longest times to surgery, radiation, and chemotherapy compared to non-Hispanic patients (surgery 38.52 vs. 31.90 days, radiation 130.12 vs. 99.67 days, chemotherapy 93.66 vs. 83.72 days, all p<0.01). Similarly, black patients and those who were uninsured had the longest times-to-treatment. CONCLUSION: We identified significant disparities in time-to-treatment, related to both race and socioeconomic factors. It is increasingly imperative to conduct further investigations into the root causes of these disparities to effectively address and rectify the inequities present in breast cancer care.

Early Stage Breast Cancer: Does Histologic Subtype (Ductal vs. Lobular) Impact 5 Year Overall Survival?

Histology is an important predictor of the behavior of breast cancer. We aim to study the impact of histology on the overall survival (OS) of breast cancer patients. We studied 11,085 breast cancer patients diagnosed with T1-T2 tumors, clinically node-negative and non-metastatic, from 2004 to 2019 included in the National Cancer Database. Kaplan-Meier curves, log-rank tests and Cox regression models were used to study the impact of histology and other variables on OS. In our patient population, 8678 (78.28%) had ductal cancer (IDC), while 2407 (21.71%) had lobular cancer (ILC). ILC patients were significantly more likely to be older, Caucasian, have a lower grade at diagnosis and be hormone receptor-positive compared to IDC patients. There was no statistically significant difference in the 5-year OS of early stage ductal (16.8%) and lobular cancer patients (16.7%) (p = 0.200). Patients of Hispanic and African American origin had worse OS rates compared to non-Hispanic and Caucasian patients, respectively. For node-positive disease, HER2+ tumors and triple-negative tumors, chemotherapy had a positive influence on OS (HR 0.85, 95% CI 0.77-0.93, p = 0.0012). Histology did not have a significant impact on the 5-year OS of early stage breast cancer patients.

Time to treatment disparities in gastric cancer patients in the United States of America: a comprehensive retrospective analysis.

Introduction: Gastric cancer ranks as the 5th most prevalent cancer and the 4th leading cause of cancer-related deaths worldwide. Various treatment modalities, including surgical resection, chemotherapy, and radiotherapy, are available for gastric cancer patients. However, disparities related to age, sex, race, socioeconomic factors, insurance status, and demographic factors often lead to delayed time to treatment. Methods: In this retrospective study, conducted between 2004 and 2019, we utilized data from the National Cancer Database (NCDB) to investigate the factors contributing to disparities in the time to first treatment, surgery, chemotherapy, and radiotherapy among gastric cancer patients. Our analysis incorporated several variables, and statistical analysis was conducted to provide valuable insights into these disparities. Results: We observed notable disparities in the timing of treatment for various demographic groups, including age, sex, race, insurance status, geographic location, and facility type. These disparities include longer time to treatment in males (32.67 vs 30.75), Native Americans (35.10 vs 31.09 in Asians), low-income patients (32 vs 31.15), patients getting treatment in an academic setting (36.11 vs 29.61 in community setting), significantly longer time to chemotherapy in 70+ age group (51.13 vs 40.38 in <40 y age group), black race (55.81 vs 47.05 in whites), low income people (49.64 vs 46.74), significantly longer time to radiotherapy in females (101.61 vs 79.75), blacks and Asians (109.68 and 113.96 respectively vs 92.68 in Native Americans) etc. There are various other disparities in time to surgery, chemotherapy, and radiotherapy. Conclusions: Understanding these disparities is crucial in developing targeted strategies to improve timely access to appropriate treatments and enhance outcomes for gastric cancer patients. Future research with updated data and prospective study designs can provide a more comprehensive understanding of the factors influencing patient outcomes in gastric cancer.

Disparities in Time to Treatment for Skin Cancer.

BACKGROUND/AIM: Skin cancer is the most common cancer worldwide. This study aimed to identify factors contributing to the disparities in skin cancer treatment. PATIENTS AND METHODS: Data from The National Cancer Database (NCDB) spanning 2004 to 2019 were utilized. Variables including age, sex, race, Hispanic origin, Charlson-Deyo Comorbidity (CDC) score, geographic location, insurance status, income, grade and stage of cancer, and type of treatment facility impacting the time to treatment, surgery, radiation, and chemotherapy were analyzed. RESULTS: Trends of longer time to treatment were seen with older age, non-Hispanic white, uninsured, those with a higher CDC score, and treated at academic facilities. Additionally, annual income and clinicopathology of cancer were also significantly associated with time to treatment. CONCLUSION: Our findings contribute to the expanding body of evidence pointing to the influence of socioeconomic and demographic factors in treatment disparities across diverse patient populations.

Inequities in Time to Treat Thyroid Cancer.

BACKGROUND/AIM: The purpose of this study was to determine socioeconomic and demographic factors which may contribute to inequities in time to treat thyroid cancer. PATIENTS AND METHODS: We used data from the National Cancer Database, 2004-2019, to conduct an analysis of thyroid cancer patients. All (434,083) patients with thyroid cancer, including papillary (395,598), follicular (23,494), medullary (7,638), and anaplastic (7,353) types were included. We compared the wait time from diagnosis to first treatment, surgery, radiotherapy, and chemotherapy for patients based on age, race, sex, location, and socioeconomic status (SES). RESULTS: A total of 434,083 patients with thyroid cancer were included. Hispanic patients had significantly longer wait times to all treatments compared to non-Hispanic patients (first treatment 33.44 vs. 20.45 days, surgery 40.06 vs. 26.49 days, radiotherapy 114.68 vs. 96.42 days, chemotherapy 92.70 vs. 58.71 days). Uninsured patients, patients at academic facilities, and patients in metropolitan areas also had the longest wait times to treatment. CONCLUSION: This study identified multiple disparities related to SES and demographics that correspond to delays in time to treatment. It is crucial that this topic is investigated further to help mitigate these incongruities in thyroid cancer care in the future.

Sociodemographic Barriers to the Timely Treatment of Pancreatic Cancer.

BACKGROUND/AIM: Pancreatic cancer has a high mortality rate and timely treatment is imperative for favorable patient outcomes. This retrospective study aimed to identify disparities in time to treatment for pancreatic cancer based on sociodemographic factors. PATIENTS AND METHODS: The study used the National Cancer Database from 2004 to 2019. A total of 423,482 patients with pancreatic cancer were included in the study. Time to first treatment, surgery, radiation, and chemotherapy were analyzed in the context of age, sex, race, Hispanic origin, insurance status, income, facility type, geographic setting, grade, stage, and Charlson-Deyo Comorbidity score (CDC). RESULTS: All sociodemographic factors included were found to be significantly associated with disparities for time to treatment in at least one of the categories studied. Minorities, treatment at academic facilities, and patients with a high CDC score had consistently longer times to all treatment classifications. CONCLUSION: The analyzed sociodemographic factors affected time to pancreatic cancer treatment. Disparities in time to treatment for pancreatic cancer must be studied and understood to ameliorate the impact this cancer has on society and assure the best possible care for all communities.