Risk factors for advanced disease in colorectal cancer

Comorbid chronic diseases and cancer diagnosis: disease-specific effects and underlying mechanisms

An earlier diagnosis is a key strategy for improving the outcomes of patients with cancer. However, achieving this goal can be challenging, particularly for the growing number of people with one or more chronic conditions (comorbidity/multimorbidity) at the time of diagnosis. Pre-existing chronic diseases might affect patient participation in cancer screening, help-seeking for new and/or changing symptoms and clinicians' decision-making on the use of diagnostic investigations. Evidence suggests, for example, that pre-existing pulmonary, cardiovascular, neurological and psychiatric conditions are all associated with a more advanced stage of cancer at diagnosis. By contrast, hypertension and certain gastrointestinal and musculoskeletal conditions might be associated with a more timely diagnosis. In this Review, we propose a comprehensive framework that encompasses the effects of disease-specific, patient-related and health-care-related factors on the diagnosis of cancer in individuals with pre-existing chronic illnesses. Several previously postulated aetiological mechanisms (including alternative explanations, competing demands and surveillance effects) are integrated with newly identified mechanisms, such as false reassurances, or patient concerns about appearing to be a hypochondriac. By considering specific effects of chronic diseases on diagnostic processes and outcomes, tailored early diagnosis initiatives can be developed to improve the outcomes of the large proportion of patients with cancer who have pre-existing chronic conditions.

Impact of comorbidity and healthcare utilization on colorectal cancer stage at diagnosis: literature review

PURPOSE

Individuals diagnosed with cancer close to death have low access to enrollment in palliative care programs. The purpose of this literature review was to assess the usefulness of pre-diagnostic comorbidity and healthcare utilization as indicators of late-stage colorectal cancer (CRC) diagnosis, to help with early identification of individuals who may benefit from palliative care.

METHODS

A literature search was conducted in relevant databases using title/abstract terms which included "cancer," "stage," "diagnosis," "determinants," "predictors," and "associated." Included studies examined whether comorbidity and/or healthcare utilization had an impact on the stage at which CRC was diagnosed. A standardized data abstraction form was used to assess the eligibility of each study. Thirteen articles were included in the literature review. These studies were assessed and synthesized using qualitative methodology.

RESULTS

We found much heterogeneity among study variables. The findings of this literature review point to the presence of comorbidity and non-emergent healthcare utilization as having no association with late-stage diagnosis. Conversely, emergency room presentation (ERP) was associated with late-stage diagnosis.

CONCLUSIONS

The results of this literature review did not find strong evidence to suggest that comorbidity and healthcare utilization are potential indicators of late-stage diagnosis. However, ERP may be useful as a flag for consideration of prompt referral to palliative care. Additional research is required to identify potential indicators of late-stage diagnosis that may be available in administrative databases, particularly in the area of healthcare utilization.

Scientific and organizational collaboration in comparative effectiveness research: the VA cooperative studies program model

Comparative effectiveness research (CER) has the ability to improve health and inform patients, clinicians, and decision makers. However, calls for more devoted efforts with regard to CER have been countered by methodological, resource, and translational challenges related to conducting these studies. The Department of Veterans Affairs (VA) Cooperative Studies Program (CSP) is a clinical research infrastructure that has contributed much evidence to support clinical practice for several decades. Although the CSP does not exclusively focus on CER, it employs strategies that lend themselves toward the planning and execution of studies that seek to compare interventions and/or strategies for treating disease. Consequently, the CSP provides a model for addressing important scientific, structural, and operational factors for clinical research, including large, national and multinational comparative effectiveness studies. Exploration of the difficulties the CSP has encountered can help to elucidate barriers that face CER. This article discusses factors and approaches for collaboratively developing and conducting definitive studies that produce outcomes aimed at influencing clinical practice, lessons that have resulted from such efforts, and ongoing challenges. Future program directions are also presented to highlight areas of emphasis and implications for CER within the VA and nationally.

Cancer of the colorectum in Maine, 1995-1998: determinants of stage at diagnosis in a rural state

CONTEXT

Despite screening for colorectal cancer, mortality in the United States remains substantial. In northern New England, little is known about predictors of stage at diagnosis, an important determinant of survival and mortality.

PURPOSE

The objective of this study was to identify predictors of late stage at diagnosis for colorectal cancer in a rural state with a predominantly white population and a large Franco-American minority.

METHODS

Incident cases from 1995-1998 were obtained from the Maine Cancer Registry. Individual-level variables (age, sex, race, French ethnicity by surname, and payer) and contextual/town-level variables (socioeconomic status, population density, Franco ancestry proportion, distance to health care, and weather) were modeled with multiple logistic regression for late stage.

FINDINGS

Increasing distance to primary care provider was associated with late stage for colorectal cancer. Compared to patients aged > or =85 years, those aged 65-84 years were less likely to be diagnosed late, while those aged 35-49 years were more likely--although not significantly--to have late stage at diagnosis. Associations were not found with socioeconomic variables.

CONCLUSIONS

The finding regarding distance to primary care may be consistent with studies showing that rurality and distance to care predict reduced utilization of health care services and worse health outcomes. The finding regarding age has implications for the education of younger high-risk patients and their physicians. The absence of positive findings with regard to socioeconomic variables may stem from the uniquely mixed sociodemographic profiles in rural and urban regions of Maine. Further research should refine these and other contextual measures to elucidate effects on rural health and should further evaluate the utility of assigning French ethnicity by surname in order to identify health disparities.

Colorectal cancer--a prospective evaluation of symptom duration and GP referral patterns in an inner city teaching hospital

OBJECTIVE

A high percentage of colorectal cancer patients (CRC) present as an emergency. Our aim was to evaluate delays in referral based on patient and general practitioner (GP) factors to see if there was any difference between elective and emergency patients.

METHOD

Symptom questionnaires were prospectively collected from 101 consecutive patients presenting to a single colorectal unit (58 male, 43 female; median age 72 years) and entered into a database. Questionnaires assessed time from symptom onset until first GP visit, time for GP to refer, and type of admission. Symptoms and Dukes stage were noted.

RESULTS

Fifty-eight (57%) patients presented electively and 43 (43%) as an emergency. Eighty-eight patients (87%) saw their GP of which 34 (39%) later presented as emergency; 13 (13%) did not see their GP. The median time before patients first sought medical advice was 30 days (0-1095 days). Median delay until treatment was 90 days (range 0-1460 days). Emergency patients waited a median of 11.5 days before visiting the GP, and elective a median of 49.5 days (P = 0.04) (Mann-Whitney U). Nine of 13 patients who did not see their GP presented as an emergency (median wait 44 days). The median time taken for a GP to refer to a hospital specialist was 28 days in elective patients and 14 days in the emergency group. (P = ns) Thirty (38%) patients took longer than six weeks to be referred (33% as an emergency). Thirty-six patients had Dukes A or B and took a median of 30 days to first presentation. Sixty-five had Dukes C or D and took a median of 32 days to first presentation. (P = ns)

CONCLUSION

Emergency patients have symptoms for less time before seeking medical advice compared to elective patients. The duration of these symptoms is unrelated to the histological stage at diagnosis. Although the majority of GPs referred CRC patients within six weeks, there was no association between time taken to refer and mode of presentation. The factors that relate to disease stage occur before symptoms are acted on.