In any type of advanced cancer, nausea and vomiting are common, independent of chemotherapy and medication regimens. Metabolic derangement, vestibular dysfunction, CNS disorders, and visceral metastasis all contribute to hyperemesis. Olanzapine has been shown to significantly reduce refractory nausea and can cause weight gain and improved appetite, which benefits cachectic patients.18
Last, clozapine is one of the more effective antipsychotic medications, but also carries a risk of neutropenia. In patients with neutropenia secondary to chemotherapy, clozapine could increase the risk of infection in an immunocompromised patient.19 Granulocyte colony stimulating factor might be useful as a rescue medication for treatment-emergent neutropenia.19
Treatment considerations
Cancer patients might be unable or unwilling to seek services for mental health during their cancer treatment, and many who have a diagnosis of psychiatric illness might stop following up with psychiatric care when cancer treatment takes priority. It is critical for clinicians to be aware of the current literature regarding the impact of mood-stabilizing medication on cancer treatment. Monitoring for drug interactions is essential, and electronic drug interaction tools, such as Lexicomp, may be useful for this purpose.13 Because of special vulnerabilities in this population, cautious and judicious prescribing practices are advised.
The risk-benefit profile for medications for bipolar disorder must be considered before they are initiated or changes are made to the regimen (Table 2). Changing an effective mood stabilizer to gain benefits in breast cancer prognosis is not recommended in most cases, because benefits have been shown to be only significant in preclinical research; currently, there are no clinical guidelines. However, medication adjustments should be made with these theoretical benefits in mind, as long as the treatment of bipolar disorder remains effective.
Regardless of what treatment regimen the health team decides on, several underlying issues that affect patient care must be considered in this population. Successfully treating breast cancer in a woman with severe mental illness only can be accomplished when her mental illness is under control. Once she is psychiatrically stable, it is important for her to have a basic understanding of how cancer can affect the body and know the reasons behind treatment.
It is imperative that physicians provide their patients with a general understanding of their comorbid disorders, and find ways to help patients remain adherent with treatment of both diseases. Many patients feel demoralized by a cancer diagnosis and adherence to a medication regimen might be a difficult task among those with bipolar disorder who also are socially isolated, lack education, or have poor recall of treatment recommendations.20
Bottom Line
Managing comorbid bipolar disorder and breast cancer might seem daunting,
but treatments for the 2 diseases can work in synergy. You have an opportunity to
educate patients and colleagues in treating bipolar disorder and comorbid breast
cancer. Optimizing care using known psychopharmacologic data can not only lead
to better outcomes, but might additionally offer some hope and reason to remain
treatment-adherent for patients suffering from this complex comorbidity.
Related Resources
• Agarwala P, Riba MB. Tailoring depression treatment for women with breast cancer. Current Psychiatry. 2010;9(11): 39-40,45-46,48-49.
• Cunningham R, Sarfati D, Stanley J, et al. Cancer survival in the context of mental illness: a national cohort study. Gen Hosp Psychiatry. 2015;37(6):501-506.
Drug Brand Names
Amiodarone • Cordarone
Aripiprazole • Abilify
Asenapine • Saphris
Bupropion • Wellbutrin
Carbamazepine • Tegretol
Citalopram • Celexa
Clozapine • Clozaril
Cyclophosphamide • Cytoxan, Neosar
Doxorubicin • Doxil, Adriamycin
Duloxetine • Cymbalta
Escitalopram • Lexapro
Fluoxetine • Prozac
Fulvestrant • Faslodex
Iloperidone • Fanapt
Lamotrigine • Lamictal
Letrozole • Femara
Lithium • Eskalith, Lithobid
Lurasidone • Latuda
Olanzapine • Zyprexa
Paclitaxel • Onxol
Paliperidone • Invega
Pamidronate • Aredia
Paroxetine • Paxil
Quetiapine • Seroquel
Raloxifene • Evista
Risperidone • Risperdal
Sertraline • Zoloft
Tamoxifen • Nolvadex
Thioridazine • Mellaril
Trastuzumab • Herceptin
Valproic acid • Depakene
Venlafaxine • Effexor
Ziprasidone • Geodon
Disclosures
The authors report no financial relationships with any company whose products are mentioned in this article or with manufacturers of competing products.