Abstract
The only approved drug for the treatment of adrenocortical cancer (ACC) is mitotane.
Mitotane is adrenolytic and therefore, hydrocortisone replacement therapy is necessary.
Since mitotane increases cortisol binding globulin (CBG) and induces CYP3A4 activity,
high doses of hydrocortisone are thought to be required. Evaluation of hydrocortisone
therapy in mitotane-treated patients has been difficult since there is no good marker
to evaluate hydrocortisone therapy. Measurement of cortisol in scalp hair is a novel
method that offers the opportunity to measure long-term cortisol levels. Our aim was
to evaluate whether hair cortisol measurements could be useful in evaluating recent
hydrocortisone treatment in mitotane-treated ACC patients. Hair cortisol levels were
measured in 15 mitotane-treated ACC patients on hydrocortisone substitution and 96
healthy individuals. Cortisol levels were measured in 3 cm hair segments, corresponding
to a period of 3 months. Hair cortisol levels were higher in ACC patients compared
to healthy individuals (p<0.0001). Seven ACC patients (47%) had hair cortisol levels
above the reference range. None of the patients had hair cortisol levels below normal.
In contrast to hydrocortisone doses (β=0.03, p=0.93), hair cortisol levels were associated
with BMI (β=0.53, p=0.042). There was no correlation between hair cortisol levels
and hydrocortisone doses (β=0.41, p=0.13). Almost half of the ACC patients had high
hair cortisol levels, suggesting long-term over-substitution of hydrocortisone in
some of the patients, whereas none of the patients was under-substituted. Hair cortisol
measurements might be useful in long-term monitoring hydrocortisone treatment in mitotane-treated
ACC patients.
Key words
hair cortisol - adrenal insufficiency - glucocorticoid replacement therapy - cortisol