Changes in Prostate Cancer Presentation Following the 2012 USPSTF Screening Statement: Observational Study in a Multispecialty Group Practice

Colorectal Cancer Diagnosis: The Obstacles We Face in Determining a Non-Invasive Test and Current Advances in Biomarker Detection

Simple Summary

Colorectal cancer (CRC) is one of the most common cancers in the western world. CRC originates from precursor adenomatous polyps, which may over time develop into cancer. Endoscopic evaluation remains the gold-standard investigation for the disease. In the absence of molecular tools for early detection, the removal of neoplastic adenomas via polypectomy remains an important measure to prevent dysplastic adenomas from evolving into invasive carcinoma. Colonoscopy is an intrusive procedure that provides an uncomfortable experience for patients. Kits for testing for the presence of blood hemoglobin in the stool are now widely used, and DNA methylation-based detection kits have been approved in the USA for testing the stool and plasma, but few other molecular biomarkers have found their way into medical practice. This review summarizes current trends in the detection and screening of CRC and provides a definitive review of emerging molecular biomarkers for CRC.

Abstract

Globally, colorectal cancer (CRC) is the third most common cancer, with 1.4 million new cases and over 700,000 deaths per annum. Despite being one of the most common cancers, few molecular approaches to detect CRC exist. Carcinoembryonic antigen (CEA) is a known serum biomarker that is used in CRC for monitoring disease recurrence or response to treatment. However, it can also be raised in multiple benign conditions, thus having no value in early detection or screening for CRC. Molecular biomarkers play an ever-increasing role in the diagnosis, prognosis, and outcome prediction of disease, however, only a limited number of biomarkers are available and none are suitable for early detection and screening of CRC. A PCR-based Epi proColon^® blood plasma test for the detection of methylated SEPT9 has been approved by the USFDA for CRC screening in the USA, alongside a stool test for methylated DNA from CRC cells. However, these are reserved for patients who decline traditional screening methods. There remains an urgent need for the development of non-invasive molecular biomarkers that are highly specific and sensitive to CRC and that can be used routinely for early detection and screening. A molecular approach to the discovery of CRC biomarkers focuses on the analysis of the transcriptome of cancer cells to identify differentially expressed genes and proteins. A systematic search of the literature yielded over 100 differentially expressed CRC molecular markers, of which the vast majority are overexpressed in CRC. In terms of function, they largely belong to biological pathways involved in cell division, regulation of gene expression, or cell proliferation, to name a few. This review evaluates the current methods used for CRC screening, current availability of biomarkers, and new advances within the field of biomarker detection for screening and early diagnosis of CRC.

Changes in Prostate-Specific Antigen Testing Relative to the Revised US Preventive Services Task Force Recommendation on Prostate Cancer Screening

Importance

In April 2017, the US Preventive Services Task Force (USPSTF) published a draft guideline that reversed its 2012 guidance advising against prostate-specific antigen (PSA)-based screening for prostate cancer in all men (grade D), instead endorsing individual decision-making for men aged 55 to 69 years (grade C).

Objective

To evaluate changes in rates of PSA testing after revisions in the USPSTF guideline on prostate cancer screening.

Design, Setting, and Participants

This retrospective cohort study used deidentified claims data from Blue Cross Blue Shield beneficiaries aged 40 to 89 years from January 1, 2013, through December 31, 2019.

Exposures

Publication of the USPSTF's draft (April 2017) and final (May 2018) recommendation on prostate cancer screening.

Main Outcomes and Measures

Age-adjusted rates of PSA testing in bimonthly periods were calculated, and PSA testing rates from calendar years before (January 1 to December 31, 2016) and after (January 1 to December 31, 2019) the guideline change were compared. Interrupted time series analyses were used to evaluate the association of the draft (April 2017) and published (May 2018) USPSTF guideline with rates of PSA testing. Changes in rates of PSA testing were further evaluated among beneficiaries within the age categories reflected in the guideline: 40 to 54 years, 55 to 69 years, and 70 to 89 years.

Results

The median number of eligible beneficiaries for each bimonthly period was 8 087 565 (range, 6 407 602-8 747 308), and the median age of all included eligible beneficiaries was 53 years (IQR, 47-59 years). Between 2016 and 2019, the mean (SD) rate of PSA testing increased from 32.5 (1.1) to 36.5 (1.1) tests per 100 person-years, a relative increase of 12.5% (95% CI, 1.1%-24.4%). During the same period, mean (SD) rates of PSA testing increased from 20.6 (0.8) to 22.7 (0.9) tests per 100 person-years among men aged 40 to 54 years (relative increase, 10.1%; 95% CI, -2.8% to 23.7%), from 49.8 (1.9) to 55.8 (1.8) tests per 100 person-years among men aged 55 to 69 years (relative increase, 12.1%; 95% CI, -0.2% to 25.2%), and from 38.0 (1.4) to 44.2 (1.4) tests per 100 person-years among men aged 70 to 89 years (relative increase, 16.2%; 95% CI, 4.2%-29.0%). Interrupted time series analysis revealed a significantly increasing trend of PSA testing after April 2017 among all beneficiaries (0.30 tests per 100 person-years for each bimonthly period; P < .001).

Conclusions and Relevance

This large national cohort study found that rates of PSA testing increased after the USPSTF's draft statement in 2017, reversing trends seen after earlier guidance against PSA testing for all patients. Increased testing was also observed among older men, who may be less likely to benefit from prostate cancer screening.

Changes in prostate cancer screening practice by blood PSA testing between 2011 and 2017, a French population-based study

OBJECTIVE

The aim of the study was to determine the trend of first blood prostate-specific antigen (PSA) test prescription in France between 2011 and 2017, based on the assumption that prostate cancer (PCa) screening is expected to decline over the years.

METHOD

Using a representative sample of the French population from the French Health Insurance database, we identified 50-52-year-old men without PCa and without any blood PSA test in the five years before 2011, 2014 and 2017 (January 1-December 31 of each year). For each of these three years, the primary outcome was the first reimbursement of a blood PSA test. We used a logistic regression model with first blood PSA test as the outcome and year as the main explanatory variable. As secondary objectives, we also identified the prescriber's specialty, the urological consultation frequency, and the number of prostate biopsies in the year after the first blood PSA test reimbursement (only for 2011 and 2014).

RESULTS

In 2011, 2014 and 2017, 5 275, 5 792 and 5 887 50-52-year-old men, respectively, were included. The percentage of patients with a first blood PSA test prescription decreased linearly from 2011 to 2017: 15.7% in 2011, 13.2% in 2014, and 12.4% in 2017 (p < .001). Blood PSA testing was mainly prescribed by general practitioners (>95%). The median interval between PSA tests was 13 months in 2011 and 14 months in 2014. Fewer than 10% of men had ≥1 consultation with an urologist during the year after the first blood PSA test. After the first blood PSA test, eight prostate biopsies were performed in 2011 and two in 2014.

CONCLUSION

Our results suggest that in France, PCa screening is a primary care issue. Although PCa screening remains controversial and confusion exists about the best practice, our study showed a linear decrease of blood PSA test prescriptions for 50-52-year-old men between 2011 and 2017, although the reason for screening was unknown. As clinical information was not available, additional evidence is needed to determine the real impact of this decrease on the cancer-specific and overall mortality.

Pentz R. Prostate Cancer: Community Education and Disparities in Diagnosis and Treatment

Prostate cancer remains the leading diagnosed cancer and the second leading cause of death among American men. Despite improvements in screening modalities, diagnostics, and treatment, disparities exist among Black men in this country. The primary objective of this systematic review is to describe the reported disparities in screening, diagnostics, and treatments as well as efforts to alleviate these disparities through community and educational outreach efforts. Critical review took place of retrospective, prospective, and socially descriptive data of English language publications in the PubMed database. Despite more advanced presentation, lower rates of screening and diagnostic procedures, and low rates of trial inclusion, subanalyses have shown that various modalities of therapy are quite effective in Black populations. Moreover, patients treated on prospective clinical trials and within equal-access care environments have shown similar outcomes regardless of race. Additional prospective studies and enhanced participation in screening, diagnostic and genetic testing, clinical trials, and community-based educational endeavors are important to ensure equitable progress in prostate cancer for all patients. IMPLICATIONS FOR PRACTICE: Notable progress has been made with therapeutic advances for prostate cancer, but racial disparities continue to exist. Differing rates in screening and utility in diagnostic procedures play a role in these disparities. Black patients often present with more advanced disease, higher prostate-specific antigen, and other adverse factors, but outcomes can be attenuated in trials or in equal-access care environments. Recent data have shown that multiple modalities of therapy are quite effective in Black populations. Novel and bold hypotheses to increase inclusion in clinical trial, enhance decentralized trial efforts, and enact successful models of patient navigation and community partnership are vital to ensure continued progress in prostate cancer disparities.

Evolution of Disparities in Prostate Cancer Treatment: Is This a New Normal?

Despite notable screening, diagnostic, and therapeutic advances, disparities in prostate cancer incidence and outcomes remain prevalent. Although commonly discussed in the context of men of African descent, disparities also exist based on socioeconomic level, education level, and geographic location. The factors in these disparities span systemic access issues affecting availability of care, provider awareness, and personal patient views and mistrust. In this review, we will discuss common themes that patients have noted as impediments to care. We will review how equitable access to care has helped improve outcomes among many different groups of patients, including those with local disease and those with metastatic castration-resistant prostate cancer. Even with more advanced presentation, challenges with recommended screening, and lower rates of genomic testing and trial inclusion, Black populations have benefited greatly from various modalities of therapy, achieving comparable and at times superior outcomes with certain types of immunotherapy, chemotherapy, androgen receptor-based inhibitors, and radiopharmaceuticals in advanced disease. We will also briefly discuss access to genomic testing and differences in patterns of gene expression among Black patients and other groups that are traditionally underrepresented in trials and genomic cohort studies. We propose several strategies on behalf of providers and institutions to help promote more equitable care access environments and continued decreases in prostate cancer disparities across many subgroups.

Evolving Natural History of Metastatic Prostate Cancer

Introduction

The systemic therapies available to patients with metastatic prostate cancer (mPC) have improved dramatically over the past decade. Anecdotal experience suggests that the increased available lines of therapy have changed the profile of mPC to include a higher prevalence of visceral metastases.

Materials and Methods

A retrospective review of 472 patients with prostate cancer who died in 2009 and in 2016 was performed. Patients with metastatic disease who had imaging within six months of death were included. A total of 164 patients were eligible for analysis.

Results

Overall rates of visceral and distant metastases, including the lung, liver, adrenal, brain, renal, spleen, and thyroid, were higher in patients who died in 2016 as compared to those who died in 2009 (40.0% and 26.1%, respectively, p-value = 0.07). Forty-four percent of patients who died in 2016 used five or more lines of systemic treatments compared to 26.1% of patients in 2009.

Conclusion

The emergence of new systemic therapies for mPC is changing the natural history of the disease. Visceral metastases are being seen with increasing frequency than in the past. This observation is important for clinicians who are monitoring patients with prostate cancer to maintain a high suspicion for visceral disease.

Assessment of Clinician Decision-making on Cancer Screening Cessation in Older Adults With Limited Life Expectancy

IMPORTANCE

Despite clinical practice guidelines recommending against routine cancer screening in older adults with limited life expectancy, older adults are still frequently screened for breast, colorectal, and prostate cancers.

OBJECTIVE

To examine primary care clinicians' decision-making on stopping breast, colorectal, or prostate cancer screening in older adults with limited life expectancy.

DESIGN, SETTING, AND PARTICIPANTS

In qualitative interviews coupled with medical record-stimulated recall, clinicians from 17 academic and community clinics affiliated with a large health system were asked how they came to specific cancer screening decisions in 2 or 3 of their older patients with less than 10-year of estimated life expectancy, including patients with and without recent screening. Patients were surveyed by telephone. Data collection occurred between October 2018 and May 2019.

MAIN OUTCOMES AND MEASURES

Clinician interviews were audio-recorded and transcribed verbatim. Transcripts were analyzed with qualitative content analysis to identify major themes. Patient surveys assessed perception of cancer screening decisions, importance of clinician recommendation, and willingness to stop screening.

RESULTS

Twenty-five primary care clinicians (mean [SD] age, 47.1 [9.7] years; 14 female [56%]) discussed 53 patients during medical record-stimulated recall, ranging from 2 to 3 patients per clinician; 46 patients and 1 caregiver (mean [SD] age 74.9 [5.4]; 31 female [66%]) participated in the survey. Clinician interviews revealed 5 major themes: (1) cancer screening decisions were not always conscious, deliberate decisions; (2) electronic medical record alerts were connected with less deliberate decision-making; (3) cancer screening was not binary and clinicians often considered other options to scale back screening without actually stopping; (4) in addition to patient characteristics, clinicians were influenced by patient request and anecdotal experiences; and (5) influences outside of the primary care clinician-patient dyad were important, such as from specialists and patients' family or friends. Patient surveys asked approximately 64 cancer screening decisions of 47 patients. Patients did not recall approximately half (31 of 64) of their cancer screening decisions. Among those with recent screening, the mean score for willingness to stop screening was 3.2 (95% CI 2.5-3.9) on a 5-point Likert scale (with 1 indicating "extremely unlikely" and 5 indicating "extremely likely"). In most screening decisions that involved specialists (13 of 16), patients valued specialists' recommendations over those of primary care clinicians.

CONCLUSIONS AND RELEVANCE

Cancer screening decision-making is complex. Study findings suggest that strategies that facilitate more deliberate decision-making may be important in cancer screening of older adults with limited life expectancy.