Purpose: To compare the neuropsychological functioning of breast cancer patients with invasive cancer and noninvasive cancer prior to adjuvant treatment.

Patients and methods: Breast cancer patients (N = 132) with invasive (Stages 1-3, N = 110, age = 54.1 +/- 8.1) or noninvasive (Stage 0, N = 22, age = 55.8 +/- 8.0) disease completed a battery of neuropsychological and psychological instruments following surgery but prior to initiation of chemotherapy, radiation or hormonal therapy. Matched healthy controls (N = 45, age = 52.9 +/- 10.0) completed the same battery of instruments. For the patients, data on menstrual status, type of surgery, time of general anesthesia, CBC and platelets, nutritional status (B12 and folate), and thyroid function were collected.

Results: Comparison of mean neuropsychological test scores revealed that all groups scored within the normal range; however, patients with Stage 1-3 cancer scored significantly lower than healthy controls on the Reaction Time domain (p = 0.005). Using a definition of lower than expected cognitive performance that corrected for misclassification error, Stage 1-3 patients were significantly (p = 0.002) more likely to be classified as having lower than expected overall cognitive performance (22%) as compared to Stage 0 patients (0%) and healthy controls (4%). No differences were observed between patients classified as having lower than expected cognitive performance compared to those classified as normal performance on measures of depression, anxiety, fatigue, menstrual status, surgery/anesthesia or any of the blood work parameters.

Conclusion: Patients with Stage 1-3 breast cancer were more likely to be classified as having lower than expected cognitive performance prior to adjuvant treatment as compared to Stage 0 patients and healthy controls, although correction for misclassification error produced a lower rate than previously reported.