Biomarkers for assessment of the polychemotherapy results in patients with adrenocortical cancer based on gas chromatography-mass spectrometry studies of urine steroid profiles

Abstract

Background: The effectiveness of polychemotherapy (PCT) for adrenocortical cancer (ACC) is assessed by imaging tests with the RECIST 1.1 criteria. However, the presence of subclinical tumor foci does not allow for an objective measurement of the true tumor burden. As shown previously, postoperative assessment of the steroid metabolome by gas chromatography-mass spectrometry (GCMS) in ACC patients makes it possible to identify early signs of adrenal steroidogenesis abnormalities and of the recurrence of adrenocortical carcinoma.
 Aim: To identify biomarkers of response to PCT by GCMS study of the urine steroid profile in ACC patients after surgical resection of the tumor.
 Materials and methods: Urine steroid profiles were studied by GCMS (Shimadzu GCMS-TQ8050 gas chromatography-mass spectrometer) in 30 ACC patients (stages II, III and IV) after surgery and first line (combination of etoposide, doxorubicin and cisplatin with daily mitotane) and second line (gemcitabine combined with capecitabine and mitotane) PCT. The control group included 25 patients with hormonally inactive adenomas.
 Results: The response to PCT according to RECIST 1.1 criteria was obtained in 23 patients (Group 1, responders) and in 7 patients ACC progressed under PCT (Group 2, non-responders). In the responders, the urinary excretion of etiocholanolone, pregnanediol and pregnanetriol was lower than in the control group. The non-responders had higher urinary excretion of androgens, progestogens and tetrahydro-11-deoxycortisol (THS), compared to the responders and the control group. The patients with ACC progression under PCT had an increase in 3β,16,20-pregnenetriol (3β,16,20-dP3) levels and a decrease of the 3α,16,20-dP3/3β,16,20-dP3 ratio, compared to those in the PCT responders. The threshold values for urinary excretion of dehydroepiandrosterone (DHEA, ≤ 469 mcg/24h; AUC = 1.0), THS (≤ 223 mcg/24h; AUC = 1.0), and 3β,16,20-dP3 (≤ 130 mcg/24h; AUC = 0.986), as well as the 3α,16,20-dP3/3β,16,20-dP3 ratio (≥ 2.13; AUC = 1.0) had 100% sensitivity and specificity for the assessment of the PCT effectiveness.
 Conclusion: Different urine steroid profiles were obtained by GCMS in the ACC patients after PCT with and without treatment response. The 100% sensitivity and specificity of the threshold values for urinary excretion of DHEA, THS, 3β,16,20-dP3 and the 3α,16,20-dP3/3β,16,20-dP3 ratio for the assessment of PCT results indicate the potential to use these parameters as biomarkers of response or progression of the disease in the monitoring of PCT effects in ACC patients.