Efficacy and safety of mitotane in the treatment of adrenocortical carcinoma: A retrospective study in 34 Belgian patients

The Effects of Cumulative Dose and Polymorphisms in CYP2B6 on the Mitotane Plasma Trough Concentrations in Chinese Patients With Advanced Adrenocortical Carcinoma

Mitotane is the only drug approved to treat adrenocortical carcinoma (ACC), and a relationship of pharmacokinetic/pharmacodynamic has been characterized. However, limited evidence concerning affecting factors in large interindividual variability of the pharmacokinetics of mitotane is available. To address this question, a retrospective analysis was performed on ACC Chinese patients treated with mitotane for more than 3 months. Mitotane plasma trough concentrations were detected at the steady state, and CYP2B6, CYP3A4, and pregnane X receptor (PXR) polymorphisms were genotyped. After examining homogeneous pharmacologic data, we restricted the analyses to 36 patients that received mitotane for a median (interquartile range, IQR) of 9 months (5.00–22.50) with a median dose of 2 g/day (2.00–2.50). As a result, drug exposure was significantly influenced by the cumulative dose of mitotane, and CYP2B6 516GG and CYP2B6 26570CC were at high risk to be below the therapeutic range of mitotane. No association was found between mitotane concentrations with CYP3A4 or PXR polymorphism. Our data firstly indicated that the cumulative dose of mitotane and polymorphisms of CYP2B6 516 and CYP2B6 26570 might significantly affect mitotane plasma trough concentrations in Chinese ACC patients.

SOAT1: A Suitable Target for Therapy in High-Grade Astrocytic Glioma?

Targeting molecular alterations as an effective treatment for isocitrate dehydrogenase-wildtype glioblastoma (GBM) patients has not yet been established. Sterol-O-Acyl Transferase 1 (SOAT1), a key enzyme in the conversion of endoplasmic reticulum cholesterol to esters for storage in lipid droplets (LD), serves as a target for the orphan drug mitotane to treat adrenocortical carcinoma. Inhibition of SOAT1 also suppresses GBM growth. Here, we refined SOAT1-expression in GBM and IDH-mutant astrocytoma, CNS WHO grade 4 (HGA), and assessed the distribution of LD in these tumors. Twenty-seven GBM and three HGA specimens were evaluated by multiple GFAP, Iba1, IDH1 R132H, and SOAT1 immunofluorescence labeling as well as Oil Red O staining. To a small extent SOAT1 was expressed by tumor cells in both tumor entities. In contrast, strong expression was observed in glioma-associated macrophages. Triple immunofluorescence labeling revealed, for the first time, evidence for SOAT1 colocalization with Iba1 and IDH1 R132H, respectively. Furthermore, a notable difference in the amount of LD between GBM and HGA was observed. Therefore, SOAT1 suppression might be a therapeutic option to target GBM and HGA growth and invasiveness. In addition, the high expression in cells related to neuroinflammation could be beneficial for a concomitant suppression of protumoral microglia/macrophages.

Metabolic and Endocrine Toxicities of Mitotane: A Systematic Review

Simple Summary

This is, to our knowledge, the first systematic review conducted on the endocrine effects of mitotane, which aims to collect all available evidence in the literature and provide complete and useful information regarding the management of the endocrine and metabolic side effects of mitotane in clinical practice.

Abstract

Despite the pivotal role of mitotane in adrenocortical carcinoma (ACC) management, data on the endocrine toxicities of this treatment are lacking. The aim of this systematic review is to collect the available evidence on the side effects of mitotane on the endocrine and metabolic systems in both children and adults affected by adrenal carcinoma. Sixteen articles on 493 patients were included. Among the adrenal insufficiency, which is an expected side effect of mitotane, 24.5% of patients increased glucocorticoid replacement therapy. Mineralocorticoid insufficiency usually occurred late in treatment in 36.8% of patients. Thyroid dysfunction is characterized by a decrease in FT4, which occurs within 3–6 months of treatment in 45.4% of patients, while TSH seems to not be a reliable marker. Dyslipidemia is characterized by an increase in both LDL-c and HDL-c (54.2%). Few studies have found evidence of hypertriglyceridemia. In males, gynecomastia and hypogonadism can occur after 3–6 months of treatment (38.4% and 35.6%, respectively), while in pre-menopausal women, mitotane can cause ovarian cysts and, less frequently, menstrual disorders. Most of these side effects appear to be reversible after mitotane discontinuation. We finally suggest an algorithm that could guide metabolic and endocrine safety assessments in patients treated with mitotane for ACC.

Multidisciplinary team therapy for left giant adrenocortical carcinoma: A case report

BACKGROUND

Adrenocortical carcinoma (ACC) is a rare malignant epithelial tumor originating from adrenocortical cells that carries a very poor prognosis. Metastatic or inoperable diseases are often considered incurable, and treatment remains a challenge. Especially for advanced cases such as ACC complicated with renal venous cancer thrombus, there are few cumulative cases in the literature.

CASE SUMMARY

The patient in this case was a 39-year-old middle-aged male who was admitted to the hospital for more than half a month due to dizziness and chest tightness. Computed tomography (CT) findings after admission revealed a left retroperitoneal malignant space-occupying lesion, but the origin of the formation of the left renal vein cancer thrombus remained to be determined. It was speculated that it originated from the left adrenal gland, perhaps a retroperitoneal source, and left adrenal mass + left nephrectomy + left renal vein tumor thrombus removal + angioplasty were performed under general anesthesia. Postoperative pathology results indicated a diagnosis of ACC. Postoperative steroid therapy was administered. At 3 mo after surgery, abdominal CT reexamination revealed multiple enlarged retroperitoneal lymph nodes and multiple low-density shadows in the liver, and palliative radiotherapy and mitotane were administered, considering the possibility of metastasis. The patient is currently being followed up.

CONCLUSION

ACC is a highly malignant tumor. Even if the tumor is removed surgically, there is still the possibility of recurrence. Postoperative mitotane and adjuvant chemoradiotherapy have certain benefits for patients, but they cannot fully offset the poor prognosis of this disease.

Determination of Mitotane (DDD) and Principal Metabolite by a Simple HPLC-UV Method and Its Validation in Human Plasma Samples

Mitotane (DDD) is prescribed in adrenocortical renal carcinoma. Its principal metabolite, dichlorodiphenylethene (DDE), can accumulate in fat tissues and from a toxicological point of view, is probably more interesting than the other metabolite dichlorodiphenylacetate (DDA). Therapeutic Drug Monitoring (TDM) of DDD plasma concentrations is required to combine therapeutic efficacy with acceptable toxicity. Therefore, we developed a simple and fast HPLC-UV method to monitor plasma concentrations after a liquid–liquid extraction of plasma calibration samples, quality controls, and anonymous plasma samples with unknown DDD and DDE concentrations. Samples were injected into an HPLC instrument and peaks of mitotane (DDD), DDE and aldrin (internal standard, IS) were resolved by a stationary phase C18 column (250 mm × 4.6 mm, 5 μm), maintained at 35 °C. Mobile phase, made by water/acetonitrile (10/90, v/v), was pumped at a flow of 1.0 mL/min, and absorbance was monitored at a wavelength of 226 nm. Average recovery was 95% for all analytes, and the method was linear for both DDD (r2 = 0.9988, range 1–50 mg/L) and DDE (r2 = 0.9964, range 1–40 mg/L). The values of limit of detection and quantitation were 0.102 and 0.310 mg/L for DDD and 0.036 and 0.108 mg/L for DDE, respectively. The retention time values of DDD, DDE and IS were 7.06, 9.42 and 12.60 min, respectively. The method was successfully validated according to FDA guidelines and finally adopted for routine TDM.

Metabolic and hormonal side effects of mitotane treatment for adrenocortical carcinoma: A retrospective study in 50 Danish patients

OBJECTIVE

Mitotane is used in the treatment of adrenocortical carcinoma (ACC). Metabolic and hormonal side effects of mitotane, the effect of subsequent treatment with statins and hormones and the effects of discontinuation of mitotane were assessed.

PATIENTS AND METHODS

Fifty patients were included. Lipid profiles, thyroid hormones, sex hormones and adrenal function from first year of mitotane treatment and after cessation were evaluated.

RESULTS

After 6 months of mitotane treatment total cholesterol increased from (median) 5.1 (IQR 4.3 to 5.8) to 7.4 (6.2-9.0) mmol/L, p < .001. LDL, HDL and triglyceride also increased, all p ≤ .03. Three months of treatment with statins decreased total and LDL-cholesterol, and cessation of mitotane led to further reduction in lipids. Plasma thyroxine decreased from 90 (78-111) to 57 (47-63) nmol/L and free thyroxine from 16.0 (13.0-18.3) to 11.7 (10.5-12.6) pmol/L on mitotane, both p < .001, while TSH remained unchanged. Treatment with thyroxin significantly increased plasma thyroxine and free thyroxine and decreased TSH. Cessation of mitotane increased total T4 (p < .001). Mitotane increased plasma SHBG from 36 (22-51) to 189 (85-259) nmol/L and LH from 4.6 (1.6-8.1) to 20.0 (10.0-34.9) IU/L, both p < .001. In males the changes were accompanied by an increase in testosterone from 9.8 (7.2-14.5) to 27.0 (15.3-34.8) nmol/L, p < .03. Fifteen of 24 tested patients regained normal adrenal function 6 (3-16) months after cessation of mitotane.

CONCLUSIONS

Mitotane treatment exerts multiple severe side effects involving both the metabolic and endocrine systems that may require treatment, but the effect appears to be partially reversible.

Pediatric adrenocortical tumor - review and management update

PURPOSE OF REVIEW

Adrenocortical tumor (ACT) is a rare disease with an annual worldwide incidence of 0.3-0.38/million children below 15 years old, and Brazilian population presents the highest incidence because of germline mutation in the TP53. Pediatric ACT is associated with virilizing features and hypercortisolism in most cases. Malignancy is defined when local invasion or metastasis is found, and it is associated with a poor prognosis. However, the correct and early diagnosis and treatment may impact on overall and disease-free survival.

RECENT FINDINGS

A complete understanding of the disease and its singularities facilitates the assistance to the pediatric patient with ACT. The new insights about adrenal tumorigenesis have provided a better understanding of this disease. In this scenario, the era of molecular studies is leading to the refinement of the taxonomy, and it is offering the opportunity to discover new biomarkers and pathways of tumorigenesis, beyond the knowing β-catenin, Insulin-like growth factor-II/IGF-IR, and the p53/Rb signaling.

SUMMARY

The rarity of this disease makes it a real challenge. Here, we present a review focusing on clinical practice. A methodic approach aiming to clarify the diagnosis and a follow-up are suggested to guide physicians in the assistance of pediatrics patients, improving the prognosis.

Hypokalaemic metabolic alkalosis, hypertension and diabetes: what is the link

Two years after diagnosis of a metastatic neuroendocrine gastrin-secreting tumour and after several cycles of chemotherapy and peptide receptor radionuclide therapy, a 56-year-old woman presented with hypokalaemic metabolic alkalosis, hypertension, leg oedema and new-onset diabetes mellitus. Further investigations revealed renal potassium loss confirmed by a transtubular potassium gradient of 16, fully suppressed serum aldosterone, but instead highly elevated blood levels of morning cortisol and adrenocorticotropic hormone as well as increased urinary excretion of glucocorticoid and mineralocorticoid metabolites. Ruling out other causes, paraneoplastic hypercortisolism was diagnosed. Pharmacological inhibition of the steroid 11β-hydroxylase with metyrapone resulted in complete resolution of metabolic alkalosis, hypokalaemia, hypertension, hyperglycaemia and leg oedema within 1 week.

Benefits of Adjuvant Mitotane after Resection of Adrenocortical Carcinoma: A Systematic Review and Meta-Analysis

Background

The adjuvant use of mitotane on adrenocortical carcinoma (ACC) has always been in controversy. We aimed to assess the prognostic benefits of adjuvant mitotane after resection of ACC in patients without distant metastasis.

Methods

The PubMed, WoS, Embase, and Cochrane Library databases were systematically searched. Recurrence-free survival (RFS) and overall survival (OS) were adopted as measurements. A meta-analysis was conducted based on hazard ratio (HR) with 95% confidence interval (CI). A study was included only if the enrolled patients underwent resection of ACC without adjuvant chemotherapy except mitotane.

Results

A total of 5 retrospective studies reporting on 1249 patients were included for this meta-analysis. The meta-analysis showed that adjuvant mitotane was significantly associated with prolonged RFS (HR = 0.62; 95%CI, 0.42-0.94; P < 0.05) and prolonged OS (HR = 0.69; 95%CI, 0.55-0.88, P < 0.05).

Conclusion

After comprehensive review, current evidence suggests that adjuvant mitotane significantly decreases the recurrence rate and mortality after resection of ACC in patients without distant metastasis, but these findings need further demonstration from prospective controlled trials.

The impact of patient-, disease-, and treatment-related factors on survival in patients with adrenocortical carcinoma

INTRODUCTION

Adrenal cortical carcinoma (ACC) is a rare and aggressive endocrine tumour. Most present with advanced disease and have poor prognosis. Optimal treatment includes complete surgical resection. There is limited evidence for the efficacy of chemotherapy and radiation at different stages in this disease. There remain many inconsistencies with respect to diagnosis and workup. There is a lack of uniform guideline recommendations and consensus data.

METHODS

We performed a retrospective chart review of all patients at London Health Sciences Centre between 1990 and 2015 using ICD coding. All paper and electronic charts were reviewed and data was collected. Statistical analysis and survival curves were performed.

RESULTS

A total of 29 patients were included in our study. Median age was 55 years (interquartile range [IQR] 45-63); 14 (48%) were male and 15 (52%) were female. Approximately half (14 or 48%) of our patients presented symptomatically. Almost half (41%) of tumours were metabolically active, producing hormones. Most (88%) underwent surgical intervention. Surgical margin status was available in about half of patients and lymphadenectomy was performed in a third (n=8) of open adrenalectomy patients. A third received mitotane treatment (8 [73%] adjuvant and 3 [27%] palliative) and a third of patients received radiation. Two- and five-year median overall survival was 53% and 27%, respectively.

CONCLUSIONS

ACC is a rare and aggressive tumour. This is the largest Canadian series reported to the best of our knowledge. Limited data for guidelines exists and treatment and workup patterns are inconsistent. Collaborative randomized and prospective studies on a global basis are needed.

Prognostic Factors of Adrenocortical Carcinoma: An Analysis of the Surveillance Epidemiology and End Results (SEER) Database

Objective: To define the prognostic factors associated with overall survival (OS) and cancer-specific survival (CSS) for adrenocortical carcinoma (ACC). Patients and Methods: We used the Surveillance, Epidemiology and End Results (SEER) database (1973-2014) to identify ACC patients. Correlated variables, including age, sex, race, tumor laterality, marital status at diagnosis, treatment of primary site, lymph node dissection, radiation therapy, chemotherapy, tumor size and tumor stage, were extracted. Univariate and multivariate Cox regression were used to define the prognostic factors. Harrell’s concordance index (C index) was calculated to evaluate the discrimination ability for the prognostic predictive models. Results: There were 749 ACC patients identified from the database. The overall median survival time was 22 (95%CI, 18-25) months. In multivariate analysis, age, treatment, chemotherapy and tumor stage were independent risk factors for both overall and cancer-specific survival. Tumor stage had a dominant effect on the cancer prognosis. Additionally, the ENSAT stage had better discrimination than the AJCC stage group in different predictive models. Conclusion: Our study shows that age, treatment of primary site, chemotherapy and tumor stage were prognostic factors for overall and cancer-specific mortality in ACC patients. Among these factors, tumor stage had a dominant effect. The ENSAT stage was more discriminative than the 7th AJCC stage group. Further multi-center prospective validation is still needed to confirm these outcomes.

ATR-101 inhibits cholesterol efflux and cortisol secretion by ATP-binding cassette transporters, causing cytotoxic cholesterol accumulation in adrenocortical carcinoma cells

BACKGROUND AND PURPOSE

To further the development of new agents for the treatment of adrenocortical carcinoma (ACC), we characterized the molecular and cellular mechanisms of cytotoxicity by the adrenalytic compound ATR-101 (PD132301-02).

EXPERIMENTAL APPROACH

We compared the effects of ATR-101, PD129337, and ABC transporter inhibitors on cholesterol accumulation and efflux, on cortisol secretion, on ATP levels, and on caspase activation in ACC-derived cell lines. We examined the effects of these compounds in combination with methyl-β-cyclodextrin or exogenous cholesterol to determine the roles of altered cholesterol levels in the effects of these compounds.

KEY RESULTS

ATR-101 caused cholesterol accumulation, ATP depletion, and caspase activation within 30 minutes after addition to ACC-derived cells, whereas PD129337 did not. Suppression of cholesterol accumulation by methyl-β-cyclodextrin or exogenous cholesterol, prevented ATP depletion and caspase activation by ATR-101. ATR-101 blocked cholesterol efflux and cortisol secretion, suggesting that it inhibited ABCA1, ABCG1, and MDR1 transporters. Combinations of ABCA1, ABCG1, and MDR1 inhibitors were also cytotoxic. Combinations of ATR-101 with inhibitors of ABCG1, MDR1, or mitochondrial functions had increased cytotoxicity. Inhibitors of steroidogenesis reduced ATP depletion by ATR-101, whereas U18666A enhanced cholesterol accumulation and ATP depletion together with ATR-101. ATR-101 repressed ABCA1, ABCG1, and IDOL transcription by mechanisms that were distinct from the mechanisms that caused cholesterol accumulation.

CONCLUSIONS AND IMPLICATIONS

Inhibition of multiple ABC transporters and the consequent accumulation of cholesterol mediated the cytotoxicity of ATR-101. Compounds that replicate these effects in tumours are likely to be useful in the treatment of ACC.

Primary site surgery for metastatic adrenocortical carcinoma improves survival outcomes: an analysis of a population-based database

OBJECTIVE

To define the survival effect of surgery of primary adrenal malignant lesions in metastatic adrenocortical carcinoma (ACC) patients.

PATIENTS AND METHODS

We used the Surveillance, Epidemiology and End Results (SEER) database (1973-2014) to identify metastatic ACC patients (stage IV by using European Network for the Study of Adrenal Tumors stage classification). Correlated variables, including age, sex, race, tumor laterality, treatment modality, lymph node dissection, surgery of metastatic site, tumor size, and tumor stage, were extracted. Univariate and multivariate Cox regression analyses were used to define the efficacy of surgery on survival outcomes, including overall survival and cancer-specific survival of ACC.

RESULTS

There were 290 metastatic ACC patients identified from the database. The overall median survival time was 7 (95% CI, 6-8) months. Among these patients, 118 patients received primary site surgery and 172 patients did not. In both univariate and multivariate analyses, primary site surgery significantly improved both overall (hazard ratio 0.413, 95% CI, 0.299-0.571, P<0.01) and cancer-specific survival (hazard ratio 0.408, 95% CI, 0.290-0.574, P<0.01) for metastatic ACC patients.

CONCLUSION

Our study suggests that primary site surgery in metastatic ACC patients significantly improved overall and cancer-specific survival. Further multicenter prospective studies are still needed to validate these outcomes.