Nearly half of the PCPs were younger than 50 years, and the majority were male, non-Hispanic white, internists, and US medical school graduates (Table ). About 60% saw fewer than five colorectal or lung cancer patients in the past year and experienced one or no barriers to referring cancer patients for more specialized care. Over three-quarters practiced in urban settings. Compared with cancer specialists, PCPs were more often female and located in rural areas. They saw fewer cancer patients and reported fewer referral barriers than did cancer specialists.
PCPs reported considerable involvement in fulfilling general medical care roles for cancer patients (Fig. ). Over 90% directly provided or co-managed the roles of managing comorbid conditions (98.2%), evaluating/treating depression (96.0%), establishing DNR status (95.0%), referring to hospice (94.7%), and prescribing opiates for cancer pain (91.2%). More PCPs directly provided than co-managed comorbid conditions and evaluating/treating depression, while the opposite was true for the other three roles. In contrast, cancer specialists were less involved in general medical care roles. Over 70% indicated that they referred patients to another provider for management of comorbid conditions or were not involved in this care. Over 50% referred patients for or were not involved in depression evaluation/treatment. Higher proportions of cancer specialists directly provided or co-managed opiate prescription for pain management (69.8%), establishment of DNR status (82.2%), and referral to hospice (78.4%).
Figure 1 Involvement of primary care physicians (PCP) and cancer specialists (CS) in fulfilling general medical care roles for cancer patients (=3315).
Compared with general medical care roles, PCPs reported less involvement in cancer care roles (Fig. ). Assessing patient preferences for treatment (64.2%) and deciding on possible use of surgery (53.7%) were the only cancer care roles directly provided or co-managed by most PCPs. PCP involvement in other cancer care roles was more limited: establishing goals for treatment and prognosis (45.6%), deciding on possible use of radiotherapy (33.7%) or chemotherapy (30.2%), determining the first treatment modality (28.2%), and discussing possible participation in clinical trials (19.3%). Considerably more PCPs co-managed than directly performed cancer care roles. In contrast, over 90% of cancer specialists reported that they establish goals for treatment and prognosis, assess patients’ treatment preferences, determine the first treatment modality, and decide on use of surgery. Somewhat fewer fulfilled the roles of deciding on use of radiotherapy (77.1%) or chemotherapy (74.1%) and discussing clinical trial participation (67.4%).
Figure 2 Involvement of primary care physicians (PCP) and cancer specialists (CS) in fulfilling cancer care roles for cancer patients (=3315).
PCPs and cancer specialists differ in the number of general medical care roles, cancer care roles, and total roles fulfilled (Fig. ). The mean number of general medical care roles fulfilled was 4.8 (SD
0.7) for PCPs and 3.0 (SD
1.5) for cancer specialists. The mean number of cancer care roles fulfilled was 2.7 (SD
2.3) for PCPs and 5.9 (SD
1.6) for cancer specialists. The mean number of total roles fulfilled was 7.5 (SD
2.6) for PCPs and 8.9 (SD
2.6) for cancer specialists.
Figure 3 Number of General Medical Care Roles, Cancer Care Roles, and Total Roles Fulfilled by Primary Care Physicians and Cancer Specialists for Cancer Patients (=3315).
Characteristics associated with fulfilling a greater number of cancer care roles among PCPs in adjusted analyses are shown in Table . PCPs aged 50 years and older fulfilled more cancer care roles than those less than 40 years. Internists and geriatricians reported more cancer care involvement than did family physicians and general practitioners. PCPs engaged in teaching fulfilled more cancer care roles than others, as did those who saw more cancer patients or reported more barriers to referring cancer patients to specialists. In contrast, PCPs who were of Hispanic (vs. white) race/ethnicity, international medical school graduates (vs. US medical school graduates), or in a government-owned practice setting (vs. physician-owned practice setting) fulfilled fewer cancer care roles. Rural practice location was not associated with the number of cancer care roles fulfilled by PCPs.
The ordered logistic regression model assessing characteristics of PCPs who fulfill more total roles (general and cancer care) showed very similar results (Table ), with two exceptions: PCPs who were of Hispanic (vs. white) race/ethnicity did not fulfill fewer roles overall, and those engaged in teaching did not fulfill more roles compared with nonteaching PCPs.
The subset modeling using data from the Iowa, Alabama, and North Carolina study sites revealed results similar to the main analysis (data not shown). Rural practice location was not associated with either the number of cancer care roles or the total number of roles fulfilled. PCPs in North Carolina fulfilled fewer cancer care roles (OR
0.62; 95% CI: 0.40–0.96) and PCPs in Alabama fulfilled more cancer care roles (OR
1.52; 95% CI: 1.01–2.27) than PCPs in Iowa, suggesting geographic variation in the cancer care practices of PCPs.