Assessing the Total Cost of Chemotherapy-Induced Toxicities

Chemotherapy-induced toxicities often adversely affect patients’ health and treatment plans, and can result in large costs for treatment and care. In addition to the costs associated with direct medical care, a large amount of indirect and out-of-pocket costs can be incurred.

However, to date, there is surprisingly limited literature on the total costs of care associated with cancer chemotherapy-related toxicities. Most of the studies in this area have evaluated the costs paid by the insurer (direct medical costs), and few have attempted to assess the indirect costs that are often borne by the patient, family, and caregivers.

Assessing these costs requires detailed and comprehensive information about patient and caregiver work loss, changes in work productivity, and the value of resources used to care for patients with such toxicities. This indirect cost information cannot be abstracted directly from patients’ charts and usually requires input directly from the patient and family and friends who assist in patient care.

In a pilot study examining the costs of treatment for 83 ovarian cancer patients, we attempted to evaluate the feasibility of assessing the total direct and indirect costs incurred. Comprehensive cost information was collected for each patient via questionnaires that were filled out at regular intervals regarding the resources used for treatment and patient care for each episode of toxicity (Calhoun EA, Chang C-H, Welshman EE, et al: Evaluating the total costs of chemotherapy-induced toxicity: Results from a pilot study with ovarian cancer patients. The Oncologist 6:441-445, 2001).

Collection of Data

Ovarian cancer patients who experienced neutropenia (n = 26), thrombocytopenia (n = 15), or neurotoxicity (n = 42) reported information about hospitalizations, medications, laboratory tests, physician visits, phone calls, home visits, medical devices, lost productivity, and caregivers’ expenditures resulting from toxicity occurrence.

Patients were contacted within 1 month of experiencing the toxicity episode and were followed for a period of time during which the toxicities were likely to have had an effect on the patient’s life, as determined by gynecologic oncologists. Patients experiencing hematologic toxicities were asked to supply follow-up information after 3 months, while patients experiencing neurotoxicity were given follow-up interviews every 3 months for 9 months.

Prices were determined by applying costs units to each resource used for patient care and treatment of the toxicity. Unit costs for direct medical expenditures were taken from standard sources such as the Red Book for pharmaceuticals and the Medicare Physician Fee Schedule for outpatient services. Indirect costs were based on modified labor force, employment, and earnings data collected by the US Census Bureau.

Direct Medical Costs

Direct medical costs were highest for neutropenia (mean of $7,546 per episode), intermediate for thrombocytopenia (mean of $3,268 per episode), and lowest for neurotoxicity (mean of $688 per episode). This reflects the marked differences in approaches to the treatment of these toxicities.

Hospital inpatient costs accounted for more than 80% of the total direct costs for patients experiencing hematologic toxicities. For patients experiencing neutropenia, drugs and devices accounted for the second largest fraction (10%) of total direct costs, while both hospital inpatient costs and laboratory tests were the second largest sources (both 8%) of direct costs for patients experiencing thrombocytopenia.

Since patients experiencing neurotoxicity do not usually require inpatient care, outpatient pharmaceuticals and devices accounted for the majority (63%) of the total direct costs. Physician visits were the second largest source of costs for patients experiencing neurotoxicity, accounting for 31% of total direct costs.

Indirect costs related to neutropenia, thrombocytopenia, and neurotoxicity were similar—$3,834, $4,282, and $4,220, respectively—although the sources of these costs differed.

For patients experiencing hematologic toxicities, patient work loss was the main source of indirect costs, accounting for 63% and 50% of the total indirect costs for neutropenia and thrombocytopenia, respectively. In general, wage loss was an important factor in indirect costs for hematologic toxicities, since hematologic toxicities are more likely to require inpatient care for treatment.

In contrast, for patients experiencing neurotoxicity, patient work loss comprised only 15% of the total indirect costs. Caregiver work loss accounted for 67% of the indirect costs incurred.

It should be noted that 52% of the ovarian cancer patients enrolled in the study were not working at the time of diagnosis and, thus, did not lose wages as a result of the toxicity. In addition, a total of 17 patients, 15 neurotoxicity patients and 2 neutropenia patients, stopped working as a result of toxicity.

Total Costs

In total, the mean overall costs per patient for neutropenia, thrombocytopenia, and neurotoxicity were $11,380, $7,550 and $4,908, respectively. Indirect costs accounted for 34% to 86% of the total costs

Of the three chemotherapy-associated toxicities, neutropenia was the most expensive in terms of treatment and patient care. The bulk of the total cost (66%) was attributed to direct medical expenditures, particularly hospital inpatient costs. In contrast, 86% of the total costs for neurotoxicity were attributed to indirect costs, primarily as a result of caregiver work loss. Indirect costs also accounted for the majority of the cost of treatment for thrombocytopenia, but to a lesser degree (57% of the total cost).

Future Cost Studies

The results of this pilot study imply that assessments of the total costs of chemotherapy-induced toxicities, including indirect and out-of-pocket costs, should be included in costs of cancer care studies. Excluding indirect and out-of-pocket costs is likely to result in an underestimation of the true value to society of the resources used for the treatment and patient care associated with chemotherapy-associated toxicities.

While assessing these costs requires comprehensive information about patients’ work activities and medically related expenses, it is certainly feasible via patient surveys and interviews.

A similar study examining the out-of-pocket and indirect costs of patients with breast, lung, prostate, or colon cancer is currently in progress at Northwestern University. The study also utilizes patient reporting to collect economic data. In addition, patients are asked to complete a 6-month logbook detailing their out-of-pocket costs for cancer-related treatment and care. 

Ms. Lee and Ms. Newlin are project managers, Northwestern University Medical School. Dr. Calhoun is assistant professor of urology, Northwestern University Medical School. Dr. Bennett is professor of medicine, Northwestern University Medical School, Robert H. Lurie Comprehensive Cancer Center, and director of HSR&D, VA Chicago Health Care System—Lakeside Division.