Breast cancer recurrence risk in relation to antidepressant use after diagnosis

Abstract

Background-While laboratory data suggest that antidepressants may promote mammary tumor growth, there has been little research investigating whether antidepressant use after breast cancer diagnosis is associated with the risk of breast cancer recurrence.

Antidepressant use and risk of central nervous system metastasis

“…Although concern exists with the Norwegian study, this trend in age is supported by other research [256] Research regarding antidepressant use among cancer patients is sparse and is usually gleaned from self-report or prescription patterns [254]. Among newly diagnosed male and female cancer patients, SSRIs use is self-reported in 15.65% [257]; this selfreport was substantiated by 18.6% of breast cancer patients' pharmacy records demonstrating SSRI use [258]. Another study found antidepressants were self-reported in 27% of breast cancer patients; this percentage increased to 32% in patients with lymphedema [259].…”

“…The effect of tamoxifen was reduced in patients taking antidepressants resulting in a significantly higher 2-year breast cancer recurrence rate, 13.9% compared to 7.5% in patients not taking antidepressants with tamoxifen (HR 1.92, 95% CI 1.33-2.76, p < 0.001) [277]. In contrast to these findings, many studies suggest no association between antidepressants and breast cancer recurrence, even though this contradicts the biology [258,272,278,279]. Reasons for this inconsistency in previous studies include differences in SSRI inhibition ability, genomic differences, differences in data collection, limited information on tamoxifen compliance, and small sample size [274].…”

“…A waiting room sample of breast cancer patients revealed that 34% of the population was prescribed antidepressants [255]. Overall, rates of antidepressant use in breast cancer population ranged from 11% to 34% [11,239,[255][256][257][258][259][260][261]. Among patients diagnosed with melanoma, rates ranged from 10.1% to 24.9% [262], and 15% of NHL patients used tricyclic antidepressants [263].…”

“…The idea that the decrease in tamoxifen activity by antidepressants affects breast cancer recurrence has been widely debated [258,272,274,[277][278][279]. The effect of tamoxifen was reduced in patients taking antidepressants resulting in a significantly higher 2-year breast cancer recurrence rate, 13.9% compared to 7.5% in patients not taking antidepressants with tamoxifen (HR 1.92, 95% CI 1.33-2.76, p < 0.001) [277].…”

“…Studies exist determining if an association exists between antidepressant use and cancer risk [264][265][266][267][268][269][270]283] and antidepressant use and recurrence of cancer [258,272,277,278], but to our knowledge, no studies exist determining if antidepressant use is associated with an increase in brain metastasis in humans. Shapovalov et al found an association between pretreatment with fluoxetine, a selective serotonin reuptake inhibitor (SSRI), and an increase in brain metastasis from breast cancer in mice [14].…”