Received: 25 December 2018 | Accepted: 4 February 2019 DOI: 10.1002/jcb.28771 PROSPECTS Thyroid function following breast cancer chemotherapy: A systematic review Keywan Mortezaee 1 | Amirhossein Ahmadi 1 | Hamed Haghi‐Aminjan 2 | Neda Khanlarkhani 3 | Ensieh Salehi 3 | Maryam Shabani Nashtaei 3,4 | Bagher Farhood 5 | Masoud Najafi 6 | Amirhossein Sahebkar 7,8,9 1 Department of Anatomy, School of Medicine, Kurdistan University of Medical Sciences, Sanandaj, Iran 2 Department of Toxicology and Pharmacology, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran 3 Department of Anatomy, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran 4 Infertility Department, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran 5 Department of Medical Physics and Radiology, Faculty of Paramedical Sciences, Kashan University of Medical Sciences, Kashan, Iran 6 Radiology and Nuclear Medicine Department, School of Paramedical Sciences, Kermanshah University of Medical Science, Kermanshah, Iran 7 Neurogenic Inflammation Research Center, Mashhad University of Medical Sciences, Mashhad, Iran 8 Biotechnology Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran 9 School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran Correspondence Bagher Farhood, Department of Medical Physics and Radiology, Faculty of Paramedical Sciences, Kashan University of Medical Sciences, Kashan. Iran. Email:bffarhood@gmail.com Masoud Najafi, Radiology and Nuclear Medicine Department, School of Paramedical Sciences, Kermanshah University of Medical Science, Kermanshah, Iran. Email: najafi_ma@yahoo.com Amirhossein Sahebkar, Biotechnology Research Center, Mashhad University of Medical Sciences, Mashhad 9177948564, Iran. Email: sahebkara@mums.ac.ir; amir_saheb2000@yahoo.com Abstract Background: Chemotherapy, as a systemic therapy, is one of the most effective modalities for cancer treatment. However, the use of chemotherapeutic drugs in patients with breast cancer can lead to thyroid dysfunction. This systematic review summarizes the available data on thyroid function following breast cancer chemotherapy. Methods: To illuminate the thyroid toxicities induced by different chemother- apy regimens in patients with breast cancer, a systematic search was done in accordance with Preferred Reporting Items for Systematic Reviews and Meta‐ Analyses guideline in Scopus, Embase, PubMed and Web of Science electronic databases up to December 2018. On the basis of a set of prespecified inclusion and exclusion criteria, eight eligible articles providing data on thyroid function following chemotherapy in patients with breast cancer were included in the study. Results: According to the obtained results, it was found that for most cases, the levels of triiodothyronine (T3), free T3 (FT3), thyroxin (T4) and free T4 (FT4) hormones decrease following breast cancer chemotherapy regimens used in these eligible studies. However, alteration of thyroid‐stimulating hormone (TSH) level after breast cancer chemotherapy was not clear. Conclusion: The findings showed that thyroid function and TSH hormone level can change in patients with breast cancer receiving different chemother- apy regimens. KEYWORDS breast cancer, chemotherapy, systematic review, thyroid function J Cell Biochem. 2019;1-7. wileyonlinelibrary.com/journal/jcb © 2019 Wiley Periodicals, Inc. | 1