Disparities in access to health care system as determinant of survival for patients with pancreatic cancer in the State of São Paulo, Brazil

Development of a blood-based extracellular vesicle classifier for detection of early-stage pancreatic ductal adenocarcinoma

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) has an overall 5-year survival rate of just 12.5% and thus is among the leading causes of cancer deaths. When detected at early stages, PDAC survival rates improve substantially. Testing high-risk patients can increase early-stage cancer detection; however, currently available liquid biopsy approaches lack high sensitivity and may not be easily accessible.

METHODS

Extracellular vesicles (EVs) were isolated from blood plasma that was collected from a training set of 650 patients (105 PDAC stages I and II, 545 controls). EV proteins were analyzed using a machine learning approach to determine which were the most informative to develop a classifier for early-stage PDAC. The classifier was tested on a validation cohort of 113 patients (30 PDAC stages I and II, 83 controls).

RESULTS

The training set demonstrates an AUC of 0.971 (95% CI = 0.953-0.986) with 93.3% sensitivity (95% CI: 86.9-96.7) at 91.0% specificity (95% CI: 88.3-93.1). The trained classifier is validated using an independent cohort (30 stage I and II cases, 83 controls) and achieves a sensitivity of 90.0% and a specificity of 92.8%.

CONCLUSIONS

Liquid biopsy using EVs may provide unique or complementary information that improves early PDAC and other cancer detection. EV protein determinations herein demonstrate that the AC Electrokinetics (ACE) method of EV enrichment provides early-stage detection of cancer distinct from normal or pancreatitis controls.

Targeting KRAS in Pancreatic Ductal Adenocarcinoma: The Long Road to Cure

Pancreatic ductal adenocarcinoma (PDAC) remains an important cause of cancer-related mortality, and it is expected to play an even bigger part in cancer burden in the years to come. Despite concerted efforts from scientists and physicians, patients have experienced little improvement in survival over the past decades, possibly because of the non-specific nature of the tested treatment modalities. Recently, the discovery of potentially targetable molecular alterations has paved the way for the personalized treatment of PDAC. Indeed, the central piece in the molecular framework of PDAC is starting to be unveiled. KRAS mutations are seen in 90% of PDACs, and multiple studies have demonstrated their pivotal role in pancreatic carcinogenesis. Recent investigations have shed light on the differences in prognosis as well as therapeutic implications of the different KRAS mutations and disentangled the relationship between KRAS and effectors of downstream and parallel signaling pathways. Additionally, the recognition of other mechanisms involving KRAS-mediated pathogenesis, such as KRAS dosing and allelic imbalance, has contributed to broadening the current knowledge regarding this molecular alteration. Finally, KRAS G12C inhibitors have been recently tested in patients with pancreatic cancer with relative success, and inhibitors of KRAS harboring other mutations are under clinical development. These drugs currently represent a true hope for a meaningful leap forward in this dreadful disease.

Current clinical practice in the management of Brazilian patients with potentially resectable pancreatic ductal adenocarcinoma (PDAC)

BACKGROUND AND OBJECTIVES

We aimed to describe the routine clinical practice of physicians involved in the treatment of patients with localized pancreatic ductal adenocarcinoma (PDAC) in Brazil.

METHODS

Physicians were invited through email and text messages to participate in an electronic survey sponsored by the Brazilian Gastrointestinal Tumor Group (GTG) and the Brazilian Society of Surgical Oncology (SBCO). We evaluated the relationship between variable categories numerically with false discovery rate-adjusted Fisher's exact test p values and graphically with Multiple Correspondence Analysis.

RESULTS

Overall, 255 physicians answered the survey. Most (52.5%) were medical oncologists, treated patients predominantly in the private setting (71.0%), and had access to multidisciplinary tumor boards (MTDTB; 76.1%). Medical oncologists were more likely to describe neoadjuvant therapy as beneficial in the resectable setting and surgeons in the borderline resectable setting. Most physicians would use information on risk factors for early recurrence, frailty, and type of surgery to decide treatment strategy. Doctors working predominantly in public institutions were less likely to have access to MTDTB and to consider FOLFIRINOX the most adequate regimen in the neoadjuvant setting.

CONCLUSIONS

Considerable differences exist in the management of localized PDAC, some of them possibly explained by the medical specialty, but also by the funding source of health care.

Short-term survival of patients with advanced pancreatic cancer admitted to intensive care unit: a retrospective cohort study

Background

Little is known about the outcomes of patients with advanced pancreatic cancer admitted to the intensive care unit (ICU) due to medical complications. We designed a study to evaluate their short-term (30-day) survival, predictors of short-term survival and chances of additional chemotherapy.

Methods

We reviewed all patients with advanced (stage III or IV) pancreatic adenocarcinoma admitted to an ICU in a dedicated Brazilian cancer centre from 2009 to 2018 due to medical reasons. We fitted multivariate regression models to identify predictors of 30-day survival and additional systemic chemotherapy.

Results

The study population consisted of 171 patients. Ninety-four patients (55.0%) had Eastern Cooperative Oncology Group (ECOG) performance status 2-4 and 146 (85.4%) had metastatic disease. Most patients (N = 75; 43.9%) were admitted to the ICU during first-line treatment. Median overall survival was 32 days (95% confidence interval (95% CI): 20-49). Survival rate at 30 days was 50.6%. ECOG performance status 2-4 was the only variable associated with lower probability of survival at 30 days in multivariate analysis (odds ratio: 0.28; 95% CI: 0.14-0.54; p < 0.001). Overall, 58 patients (33.9%) received additional chemotherapy and among all patients, 13.5% experienced clinical benefit from this treatment.

Conclusion

Patients with advanced pancreatic cancer admitted to the ICU for medical reasons have a dismal prognosis. Early palliative care and refined tools to establish those who would benefit from an ICU trial could help improve patients' care.

The influence of socioeconomic status on access to cancer care and survival in resectable pancreatic cancer: a systematic review and meta-analysis

BACKGROUND

Socioeconomic status (SES) is an important factor affecting access to cancer care and survival. Its role in pancreatic cancer warrants scrutiny.

METHODS

A systematic review of major reference databases was undertaken. Categorization of the study population into low SES (LSES) and high SES (HSES) was based on the criteria employed in the individual studies. The outcome measures studied were stage of cancer presentation, access to care and overall survival. Meta-analysis was performed using random-effects models and trial sequential analysis (TSA) was used to assess the precision and conclusiveness of the results.

RESULTS

Thirteen studies meeting inclusion criteria were included in the meta-analysis, which demonstrated that LSES was associated with significantly lower rates of presentation at a non-metastatic stage and poorer access to cancer care, viz. surgery, chemotherapy and radiation therapy. Despite heterogeneity, TSA supported the findings, displaying minimal type I error.

CONCLUSION

As LSES is associated with delayed presentation, poorer access to care and poorer survival, SES should be considered a modifiable risk factor for poor outcomes in pancreatic cancer.

Time-to-treatment initiation for cutaneous melanoma reflects disparities in healthcare access in Brazil: a retrospective study

OBJECTIVES

This study aimed at identifying the sociodemographic and first treatment characteristics affecting time-to-treatment initiation (TTI) of patients with cutaneous melanoma assisted by the Brazilian Unified Health System (SUS).

STUDY DESIGN

Retrospective observational study using cutaneous melanoma cases recorded in the Brazilian Hospital-Based Cancer Registries (HBCR).

METHODS

A total of 12,783 cutaneous melanoma cases were included in the analysis. Based on the legislation, TTI in Brazil is 60 days; therefore, the cohort was dichotomized into TTI within 60 days and over. The association among variables was evaluated through the Chi-squared test. Kaplan-Meier method and log-rank hypothesis test were used to determine the probability of initiating treatment within 60 days. Cox proportional hazards regression model was used for multivariate analysis.

RESULTS

Median TTI was 28 days (95% CI, 25-29). First treatment in SUS provided more than 60 days after diagnosis (34.8%) was associated with females; low level of formal education; living or getting treatment in northern Brazil; being diagnosed in SUS and treated at different healthcare facilities, in addition to starting treatment with radiotherapy or systemic therapy. There were no significant differences in access to health care before and after the enactment of the 60-day law.

CONCLUSION

Increased TTI for cutaneous melanoma is associated with sociodemographic and first treatment characteristics in Brazil; approximately one-third of cases did not have access to first treatment within the period established by law. Receiving the diagnosis and treatment at different healthcare facilities (transitions in care) is the main independent factor associated with TTI longer than 60 days.