Endocrine Abstracts

Background: The late effects of childhood cancer therapy include a higher risk of subsequent primary cancers, fertility issues, and other endocrine dysfunction.

Case: A 47 year old woman was treated at age 9 for acute myeloid leukaemia with chemotherapy (DAT, MACE, and cyclophosphamide), total body irradiation (990 cGy) and allogeneic bone marrow transplantation. Aged 22, a rapidly enlarging right sided thyroid nodule developed in the context of a multinodular goitre. Histology from fine needle aspiration was inconclusive so she underwent total thyroidectomy. Two parathyroid glands were preserved. Histology showed a 9mm papillary thyroid cancer. Aged 33, on investigation for causes of secondary infertility, she was found to have premature ovarian insufficiency with LH 17 IU/l, FSH 31 IU/l, oestradiol 66 pmol/land AMH <1.5 pmol/l. Fertility treatment with donor egg IVF was unsuccessful and hormone replacement therapy was commenced. Aged 40, she developed easy bruising and a marked increase in weight over the course of a few months. A low dose dexamethasone suppression test was carried out showing a baseline ACTH of 5.8 ng/lwith a 48 hour suppressed ACTH of <5.0 ng/land a non-suppressed cortisol of 99 nmol/lconsistent with ACTH-independent hypercortisolism. CT of the adrenals showed bilateral adrenal gland enlargement and a 1.3 cm right adrenal nodule of 5 Hounsfield units. Given the bilateral enlargement and absence of metabolic complications, the decision was made for conservative management with monitoring of cardiometabolic risk factors. At the age of 42, she developed breast cancer with metastases to the pelvis and was found to have a co-existing lung adenocarcinoma. On annual review blood tests, hypercalcaemia of 2.83 mmol/lwas noted with PTH 11.5 pmol/l. Urinary calcium was low. FHH genetic testing was negative. US of the parathyroid gland showed two hyperplastic parathyroid nodules consistent with primary hyperparathyroidism.

Conclusion with points for discussion: This case illustrates the wide spectrum of late effects of childhood cancer therapy and the importance of long-term follow up and screening. Radiation to the neck predisposes to a high risk of thyroid and parathyroid dysfunction. The options for thyroid cancer surveillance include patient self-monitoring, periodic thyroid palpation and ultrasound surveillance but there is no clear consensus on which option should be used. Fertility complications are common and up to 80% of women receiving total body irradiation will develop premature ovarian failure.