. 2015 Jan 14;7:19–35. doi: 10.2147/CMAR.S75463

Table 3.

Summary of published studies on colorectal cancer among veterans, 2003–2013

Study	Study design	Study population, n		Study outcome(s)	Major findings	Single/multiple VA facility(ies)
Study	Study design	Total	VA CRC	Study outcome(s)	Major findings	Single/multiple VA facility(ies)
Abraham et al⁴¹	Retrospective cohort	197	197	Receipt of recommended therapy	Most patients with colon cancer receive recommended therapy; rectal cancer patients who were presented at tumor board were more likely to receive recommended therapy	National-level cohort
Balentine et al⁴⁰	Retrospective cohort	155	155	Disease-free survival	Obese patients had nonsignificantly decreased wound infection after minimally invasive surgery (MIS) compared to open surgery; MIS had faster return of bowel function and faster return home	Single facility (Houston, TX)
Battat et al⁷⁸	Retrospective cohort	147	147^a	Stage at diagnosis	Increase in stage 0 cancers; overall migration to earlier-stage cancers	Single facility (Palo Alto, VA health care system)
Chiao et al⁶¹	Retrospective cohort	470	470	Risk of death, quality of care	A diagnosis of diabetes did not impact overall survival among patients with CRC	Single facility (Houston, TX)
Davila et al⁵⁷	Retrospective cohort	32,621	32,621	30-day postoperative mortality	Older age, being divorced/separated/widowed, and presence of distant metastases associated with increased 30-day mortality	National-level cohort
Fernandez et al⁴⁹	Retrospective cohort	72	72	Pathologic and operative measures, postoperative morbidity	Robotic surgery patients had lower tumors, more advanced disease, higher rate of preoperative chemoradiation, longer operative times	Single facility (Houston, TX)
Fisher et al⁷⁹	Retrospective cohort	447	447	Time to diagnosis, stage at diagnosis	Older age, having comorbidities, and Atlanta region associated with longer time to diagnosis; screen detection associated with decreased risk of late-stage cancer	15 VAMCs
Fisher et al⁶⁴	Retrospective cohort	3,546	3,546	Risk of death	Risk of death decreased in patients who had at least 1 follow-up colonoscopy	National-level cohort
Gellad et al⁸⁰	Prospective cohort	3,121	3,121^a	Risk of neoplasia, adenoma detection	Withdrawal time not associated with risk of interval neoplasia; at medical-center level, withdrawal time associated with baseline adenoma detection	13 VAMCs
Gonsalves et al⁵¹	Retrospective cohort	19,240	19,240	Number of lymph nodes recovered	Later year at diagnosis, higher overall stage, higher T descriptor, age less than 65 years, poorer differentiation, right-sided tumor associated with an increased probability of retrieving 12 or more lymph nodes after surgical resection	National-level cohort
Hachem et al⁸¹	Case control	30,400	6,080	Risk of CRC	Use of statins associated with small reduction in risk of colon cancer in patients with diabetes	National-level cohort
Hamilton et al⁶⁵	Retrospective cohort	1,199	1,199	Use of psychosocial support services	Rectal cancer patients less likely to receive psychosocial services	27 VAMCs
Hou et al⁸²	Retrospective cohort	20,949	20,949	Risk of CRC	African-Americans not at an increased risk for CRC compared to Caucasians	National-level cohort
Hynes et al⁴²,^c	Retrospective cohort	601	601	Receipt of surgery and chemotherapy	Older veterans with colon cancer who used both VA and non-VA services had similar odds of receiving cancer-directed surgery and chemotherapy in both systems	California
Itani et al³⁹	Retrospective cohort	103	103	30-day postoperative mortality	22% had a delay in surgery and the use of minimally invasive surgery increased over time	118 VAMCs
Keating et al⁶,^b,^c	Retrospective cohort	Not reported	Not reported	Variation in treatment and outcomes by area-level Medicare spending	In the VA cohort, no associations of care or mortality with Medicare spending	National-level cohort
Keating et al⁷,^b,^c	Retrospective cohort	23,327	2,915	End-of-life care	Men in VA less likely to receive chemotherapy within 14 days of death, be admitted to ICU within 30 days of death, or have >1 ER visit within 30 days of death, compared to fee-for-service Medicare	National-level cohort
Landrum et al¹⁷,^b	Retrospective cohort	5,348 (full cohort), 584 (sample)	2,396 (full cohort), 407 (sample)	Underuse of recommended treatment	African-Americans with rectal cancer less likely to receive rectal surgery; higher refusal rates for curative rectal cancer surgery among African-Americans	Random sample of national- level cohort
Landrum et al⁸,^b,^c	Retrospective cohort	94,013	8,760	All-cause and cancer-specific survival rates	Similar survival rates for colon and rectal cancer; earlier stage at diagnosis associated with survival	National-level cohort
Lee et al⁵⁰	Retrospective cohort	47	47	LOS, ICU stay, complications, 30-day mortality	Patients over 80 years old had increased LOS, more cardiopulmonary complications, and decreased survival rates	Single facility (Houston, TX)
Leung et al⁸³	Retrospective cohort	186	186	Postoperative hospital LOS	CAD and postoperative complications associated with prolonged LOS; COPD predictive of complications	Single facility (Richmond, VA)
Lieberman et al⁸⁴	Prospective cohort	1,171	30	Cumulative most advanced histologic finding at colonoscopy	Among those with CRC, 23% had family history, 67% had history of smoking, 77% used nonsteroidal anti-inflammatory drugs	National-level cohort
Mammen et al⁶³	Retrospective cohort	5,823	5,823	Overall survival	Age, grade, number of nodes associated with overall survival for patients with stage I–III disease	National-level cohort
Marshall et al⁵⁴	Retrospective cohort	50	50	Overall inpatient cost and LOS	LOS and operative times shorter among patients who had laparoscopic colectomy	Single facility (Houston, TX)
Mauchley et al³⁸	Prospective cohort	130	130	Impact of CT scans on treatment; cost	CT scans altered treatment for 16% of patients; saved the facility US$24,018 over 6 years	Single facility (VA Puget Sound health care system in Seattle, WA)
Merkow et al⁴⁶	Retrospective cohort	17,487	17,487	Time from diagnosis to definitive cancer-directed therapy	Time from diagnosis to first treatment increased over the study period (1998–2008)	124 VAMCs
Paulson et al⁴⁵	Retrospective cohort	4,635	4,635	Time from diagnosis to surgery, time from surgery to initiation of chemotherapy	Treatment at multiple hospitals or surgery outside of the VA system more likely to experience delays than patients treated in a single hospital	National-level cohort
Pérez et al⁸⁵	Retrospective cohort	405	405^a	Risk factors, sporadic hyperplastic polyps and colorectal neoplasia	Hyperplastic polyps not associated with colorectal neoplasia; proposed risk factors for colorectal neoplasia not risk factors for developing hyperplastic polyps	VA Caribbean health care system
Phelan et al⁶⁶	Cross-sectional survey	1,109	1,109	Depressive symptoms	Cancer stigma and self-blame associated with depressive symptoms	National-level cohort
Rabeneck et al⁶²	Retrospective cohort	22,633	22,633	Mortality	Greater hospital surgical volume associated with prolonged long-term survival following surgery	National-level cohort
Rabeneck et al⁶⁰	Retrospective cohort	34,888	34,888	Mortality	Older age associated with increased short- and long-term mortality	National-level cohort
Rabeneck et al⁵⁶	Retrospective cohort	46,044	46,044	Survival	Decrease in chance of survival in blacks compared with whites; overall survival improved over time	National-level cohort
Robinson et al⁴⁸	Retrospective cohort	214	214	Time from diagnosis to surgery and survival time	No difference by race in stage of disease at presentation, mean time from diagnosis to surgery, or survival	Single facility (Houston, TX)
Sabounchi et al⁴³	Retrospective cohort	300	300	Treatment, survival outcomes	No racial differences in tumor grade, extent of disease, receipt of curative surgery, time to death	Single facility (Houston, TX)
Siersema et al⁸⁶	Case-control	536	268	Risk of colorectal neoplasia	Barrett’s esophagus, age, and alcohol use associated with increased risk of colorectal neoplasia	Single facility (Palo Alto Veterans Affairs health care system)
Tarlov et al⁹,^c	Retrospective cohort	3,014	3,014	Overall survival and event-free survival	Improved survival among patients who received all care in either VA or non-VA (ie, not dual users)	National-level cohort
Tarlov et al³⁷,^b	Retrospective cohort	21,239	4,225	Changes in ESA use for anemia treatment	After black-box warning, ESA use decreased 53% among colon cancer patients; odds of ESA use increased with advancing age; postperiod decline in use was much larger at younger ages and diminished throughout the age span	National-level cohort
van Roessel et al⁵⁹	Retrospective cohort	334	334^a	Tumor stage, tumor location, survival	All-cause 5-year survival significantly better for VA CRC cohort compared to National Cancer Database cohort	Single facility (Palo Alto, VA health care system)
Visser et al⁵⁸	Prospective cohort	186	186	30-day and 90-day mortality	30-day mortality underreports true risk of death after colorectal surgery, 90-day mortality rate is a better estimation	Single facility (Palo Alto, VA health care system)
Wahls and Peleg⁸⁷	Retrospective cohort	150	150	Delays or nonreceipt of CRC screening	Frequency (65%) of included cases missed opportunities for earlier diagnosis, 38% had contributing patient factors	Rural VA health care system in upper Midwest
Wilks et al⁵³	Prospective database	120	60^a	LOS, postoperative outcomes, complications	Laparoscopic resections associated with shorter hospital stays, quicker return of bowel function, fewer wounds, fewer complications requiring reoperation	Single facility (Houston, TX)
Wilks et al⁵²	Retrospective and prospective cohorts	346	346^a	Quality of care	Quality of care (ie, complete, margin-negative resections, lymph nodes excised, multidisciplinary therapy) improved after implementation of dedicated center	Single facility (Houston, TX)
Zafar et al¹⁰,^c	Retrospective cohort	682	342	Stage at diagnosis	In VA cohort, higher comorbidity associated with earlier stage at diagnosis	15 VAMCs
Zeber et al¹⁹,^b	Retrospective cohort	194,797	26,300	Treatment	Differences in rate of receipt of radiation, chemotherapy, surgery with oldest patients (≥85 years) receiving lower rate of treatment compared to those aged 70–84 years of age	National-level cohort
Zullig et al⁵,^b	Retrospective cohort	39,505	3,421	Incidence in VA	Colon and rectal cancers represent 9% of all cancers in VA, proportions of CRC similar by race and sex	National-level cohort
Zullig et al⁴⁴	Retrospective cohort	2,022	2,022	Guideline treatment	No racial differences in receipt of care, older age at diagnosis and cardiovascular comorbid conditions associated with reduced odds of medical oncology referral, older age also associated with reduced odds of surveillance colonoscopy	National-level cohort
Zullig et al⁴⁷	Retrospective cohort	2,022	2,022	Treatment timeliness, survival outcomes	Small racial difference in timing of surveillance colonoscopy, little evidence of racial differences in CRC-care quality	National-level cohort

Notes:

Did not clearly distinguish between precancerous, noninvasive, and/or invasive CRC

addressed both lung cancer and CRC

included both VA and non-VA health care settings.

Abbreviations: CRC, colorectal cancer; COPD, chronic obstructive pulmonary disease; LOS, length of stay; ICU, intensive care unit; CAD, coronary artery disease; ER, emergency room; VAMC, Veterans Affairs Medical Center; ESA, erythropoiesis-stimulating agent; DNR, do not resuscitate; CT, computed tomography; VA, Veterans Affairs.