Growth hormone replacement in patients with a history of malignancy: a review of the literature and best practice for offering treatment

Abstract

Previous studies have implicated the growth hormone (GH)/IGF-I axis as an important mediator of cancer risk in humans and animals. Evidence supporting this notion is derived from animal studies, epidemiological observations, patients with acromegaly and from therapeutic manipulation of GH and IGF-I actions. Therefore, the use of GH therapy in patients with a history of malignancy raises hypothetical safety concerns. Reassuringly, GH therapy in childhood cancer survivors has not been confirmed to increase the cancer risk. Conversely, the risk of occurrence of a second neoplasm may be increased, with meningiomas being the most common tumor. In light of these findings, we propose considering GH therapy to be based on each individual’s circumstance and commenced at least 2 years after cancer remission is achieved with close monitoring during therapy. More long-term data are needed on the safety of GH replacement therapy in GH-deficient adults with a history of malignancy.

Keywords:

• cancer
• growth hormone
• growth hormone deficiency
• malignancy
• review

Financial & competing interests disclosure

KCJ Yuen has received research grants from Pfizer, Novo Nordisk, Eli Lilly and Versartis and has served on the advisory boards for Pfizer and Novo Nordisk. V Popovic is a member of the International Board for Nordinet – Novo Nordisk. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.

Key issues

• The potential of growth hormone (GH) acting as a mitogen has raised some safety concerns over the possibility of increased de novo tumors or hypothalamic–pituitary tumor recurrence in adults treated with GH.

• Studies of adults who received GH replacement therapy in childhood have shown that the risk of occurrence of a second neoplasm may be increased, but in adult surveillance studies, the results have been reassuring in demonstrating no increase in cancer risk or mortality.

• GH replacement is contraindicated in the presence of active malignancy.

• When considering GH therapy in adults with a previous history of malignancy, we propose initiating GH replacement therapy to be based on each individual circumstance and to be commenced at least 2 years after cancer remission is achieved with clearance from the patient’s oncologist and with close monitoring during therapy.

• Although more long-term data are needed on the safety of GH replacement therapy in GH-deficient adults with a history of malignancy, it is unlikely that such studies will be conducted in the near future.

Notes

GH: Growth hormone; GHD: GH deficiency.