CANSA Research in Action Conference – July 2018 – Poster Session for Students – Okunola Abisola
The title of the Type A grant to which the abstract relates: Application of personalised medicine using an integrated service and research approach: Evaluation of vitamin D in breast cancer patients
The name of the PI of the Type A grant to which the abstract relates: Professor Maritha J. Kotze
The title of the degree to which the applicant is working towards: PhD
High prevalence of vitamin D deficiency in postmenopausal breast cancer patients treated with aromatase inhibitors at Tygerberg Hospital
Okunola A.O 1, Sawe R.T 1, Baatjes K.J 2, Zemlin A.E 1,3, Erasmus R.T 1,3, Kotze M.J 1,3
1Division of Chemical Pathology, Faculty of Medicine and Health Sciences, Stellenbosch University, Tygerberg, South Africa.
2Department of Surgical Sciences, Faculty of Medicine and Health Sciences, Stellenbosch University, Tygerberg, South Africa.
3National Health Laboratory Service, Tygerberg Hospital, Tygerberg, South Africa.
The importance of vitamin D for prevention of osteoporosis and bone fractures is undisputed, while its role in cancer risk remains uncertain. Breast cancer patients treated with aromatase inhibitors represent an important target group for assessment of vitamin D status, since this drug is associated with increased risk of bone loss and fractures. The aim of this study was to determine vitamin D status in breast cancer patients with the luminal subtype, previously shown to correlate with clinical outcome.
A total of 126 histologically confirmed postmenopausal breast cancer patients attending the Tygerberg Hospital Breast Cancer Clinic were included in the study. Baseline data entered between 2014 and 2017 was extracted from the research database. Estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor-2 (HER2) status was determined by standard immunohistochemistry (IHC). Serum vitamin D levels were measured in the study participants by chemiluminescent immunoassay and their DNA stored for future genetic studies. The levels of vitamin D were classified as deficient (<20ng/ml), insufficient (20-29ng/ml) or sufficient (30-150ng/ml).
Pathological tumor types included 14 (11.4%) invasive lobular carcinomas, 87 (71.3%) invasive ductal carcinomas, 5 (4.1%) ductal carcinoma in situ, and 5 (4.1%) were unknown. Vitamin D levels were deficient in 53.7% (Mixed ancestry 54, Caucasian 6, Black 2, Indian3) of the patients. Insufficient levels were detected in 37.1% (Caucasian 7; mixed ancestry 36), while sufficient levels were recorded in 11.2 % (Caucasian 2; mixed ancestry 11) of study participants.
The finding that more than half of the patients have vitamin D deficiency highlighted the need for a comprehensive monitoring program aimed at improved clinical management at Tygerberg Hospital. The value of applied laboratory medicine in healthcare delivery lies in early detection of patients at increased risk of breast cancer recurrence and drug-induced side effects.