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

International consensus on mitotane treatment in pediatric patients with adrenal cortical tumors: indications, therapy, and management of adverse effects

OBJECTIVE

Mitotane is an important cornerstone in the treatment of pediatric adrenal cortical tumors (pACC), but experience with the drug in the pediatric age group is still limited and current practice is not guided by robust evidence. Therefore, we have compiled international consensus statements from pACC experts on mitotane indications, therapy, and management of adverse effects.

METHODS

A Delphi method with 3 rounds of questionnaires within the pACC expert consortium of the international network groups European Network for the Study of Adrenal Tumors pediatric working group (ENSAT-PACT) and International Consortium of pediatric adrenocortical tumors (ICPACT) was used to create 21 final consensus statements.

RESULTS

We divided the statements into 4 groups: environment, indications, therapy, and adverse effects. We reached a clear consensus for mitotane treatment for advanced pACC with stages III and IV and with incomplete resection/tumor spillage. For stage II patients, mitotane is not generally indicated. The timing of initiating mitotane therapy depends on the clinical condition of the patient and the setting of the planned therapy. We recommend a starting dose of 50 mg/kg/d (1500 mg/m²/d) which can be increased up to 4000 mg/m2/d. Blood levels should range between 14 and 20 mg/L. Duration of mitotane treatment depends on the clinical risk profile and tolerability. Mitotane treatment causes adrenal insufficiency in virtually all patients requiring glucocorticoid replacement shortly after beginning. As the spectrum of adverse effects of mitotane is wide-ranging and can be life-threatening, frequent clinical and neurological examinations (every 2-4 weeks), along with evaluation and assessment of laboratory values, are required.

CONCLUSIONS

The Delphi method enabled us to propose an expert consensus statement, which may guide clinicians, further adapted by local norms and the individual patient setting. In order to generate evidence, well-constructed studies should be the focus of future efforts.

Recovery of adrenal function after stopping mitotane in patients with adrenocortical carcinoma

OBJECTIVE

Mitotane is the standard therapy of adrenocortical carcinoma (ACC) due to its relative selectivity of its cytotoxic effects toward adrenocortical cells. Therefore, it virtually always leads to adrenal insufficiency. Frequency and characteristics of hypothalamic-pituitary-adrenal axis recovery after discontinuation are ill-defined.

METHODS

This was a retrospective study of patients with ACC adjuvantly treated with mitotane for ≥12 months who were disease-free at mitotane stop and had a minimum follow-up ≥1 year. Primary endpoint was adrenal recovery. Cox regression analyses were used to identify predictive factors. Moreover, mitotane plasma elimination rate and hormonal changes after mitotane stop were investigated.

RESULTS

Fifty-six patients (36 women) treated with mitotane for a median time of 25 months and an average daily dose of 2.8 g were included. Median time after discontinuation until mitotane levels dropped below 5 and 2 mg/L, and the detection limit was 152 days (interquartile range: 114-202), 280 days (192-370), and 395 days (227-546), respectively. Full adrenal recovery was documented in 32 (57%) patients after a median time of 26 months (95% confidence interval [CI] = 19.6-32.4). In 4 patients (7.1%), adrenal insufficiency persisted >5 years after discontinuation. Mitotane peak ≥ 27 mg/L significantly correlated with longer time to adrenal recovery (hazard ratio [HR] = 0.2, 95% CI = 0.1-0.8, P = .03). Twenty-seven of 38 patients (71%) followed in reference centers achieved adrenal recovery compared with only 5/18 (28%) followed up in non-reference centers (HR = 4.51, 95% CI = 1.71-11.89, P = .002). Other investigated factors were not associated with adrenal function after discontinuation.

CONCLUSIONS

Our study demonstrates that adrenal recovery occurs in most patients after stopping mitotane, particularly when followed up in specialized centers, but not in all. Elimination time of mitotane after treatment discontinuation is very long but individually quite variable.

Hypogonadism and sexual function in men affected by adrenocortical carcinoma under mitotane therapy

Purpose

Adrenocortical carcinoma (ACC) is a rare and aggressive tumor. ACC male patients under adjuvant mitotane therapy (AMT) frequently develop hypogonadism, however sexual function has never been assessed in this setting. The aim of this retrospective study was to evaluate in AMT treated ACC patients the changes in Luteinizing hormone (LH), Sex Hormone Binding Globulin (SHBG), total testosterone (TT) and calculated free testosterone (cFT), the prevalence and type of hypogonadism and sexual function, the latter before and after androgen replacement therapy (ART).

Methods

LH, SHBG, TT and cFT were assessed in ten ACC patients at baseline (T0) and six (T1), twelve (T2), and eighteen (T3) months after AMT. At T3, ART was initiated in eight hypogonadal patients, and LH, SHBG, TT and cFT levels were evaluated after six months (T4). In six patients, sexual function was evaluated before (T3) and after (T4) ART using the International Index of Erectile Function-15 (IIEF-15) questionnaire.

Results

Under AMT we observed higher SHBG and LH and lower cFT levels at T1-T3 compared to T0 (all p<0.05). At T3, hypergonadotropic hypogonadism and erectile dysfunction (ED) were detected in 80% and 83.3% of cases. At T4, we observed a significant cFT increase in men treated with T gel, and a significant improvement in IIEF-15 total and subdomains scores and ED prevalence (16.7%) in men under ART.

Conclusion

AMT was associated with hypergonatropic hypogonadism and ED, while ART led to a significant improvement of cFT levels and sexual function in the hypogonadal ACC patients. Therefore, we suggest to evaluate LH, SHBG, TT and cFT and sexual function during AMT, and start ART in the hypogonadal ACC patients with sexual dysfunction.

Albumin/Mitotane Interaction Affects Drug Activity in Adrenocortical Carcinoma Cells: Smoke and Mirrors on Mitotane Effect with Possible Implications for Patients' Management

BACKGROUND

Mitotane is the only drug approved for the treatment of adrenocortical carcinoma (ACC). Although it has been used for many years, its mechanism of action remains elusive. H295R cells are, in ACC, an essential tool to evaluate drug mechanisms, although they often lead to conflicting results.

METHODS

Using different in vitro biomolecular technologies and biochemical/biophysical experiments, we evaluated how the presence of "confounding factors" in culture media and patient sera could reduce the pharmacological effect of mitotane and its metabolites.

RESULTS

We discovered that albumin, the most abundant protein in the blood, was able to bind mitotane. This interaction altered the effect of the drug by blocking its biological activity. This blocking effect was independent of the albumin source or methodology used and altered the assessment of drug sensitivity of the cell lines.

CONCLUSIONS

In conclusion, we have for the first time demonstrated that albumin does not only act as an inert drug carrier when mitotane or its metabolites are present. Indeed, our experiments clearly indicated that both albumin and human serum were able to suppress the pharmacological effect of mitotane in vitro. These experiments could represent a first step towards the individualization of mitotane treatment in this rare tumor.

Neurological adverse events of mitotane in adrenocortical carcinoma: results of a pilot study

Introduction

Mitotane, the only drug approved by the Food and Drug Administration (FDA) for the treatment of adrenocortical carcinoma, is associated with several side effects including neurotoxicity. The aim of our study is to investigate the relationship between mitotane plasma levels and neurological toxicity.

Methods

We have considered five patients affected by adrenocortical carcinoma treated with mitotane. The neurological assessment included a neurological examination, an electroencephalogram, event-related potentials (P300), and a neuropsychological assessment. All of the patients were first considered at the onset of symptoms of neurotoxicity or when mitotanemia levels were above 18 mg/L, for the second time at mitotanemia normalization and subsequently at its further increase, or in case of persistent neurological abnormalities, some months after normalization.

Results

At the first neurotoxicity, four patients showed impaired neurological examination, electroencephalogram, and P300; three patients had impaired neuropsychological assessment; one patient, only P300. At mitotanemia normalization, the neurological examination became normal in all patients and electroencephalogram normalized in one patient, improved in another one, continuing to be altered in the other three. P300 latency and neuropsychological assessment normalized in two patients and persisted altered in the patient experiencing long-term mitotane toxicity. At the third evaluation, in the patient with prolonged mitotane toxicity, the normal mitotanemia in the previous 9 months restored P300 and improved the electroencephalogram but not the neuropsychological assessment. In the two patients experiencing a further rise of mitotanemia, neurological examination was normal but P300 and electroencephalogram were altered.

Conclusion

The results of our study highlighted the presence of neurophysiological and neuropsychological abnormalities associated with mitotane values above 18 mg/L.

Long-term partial response in a patient with liver metastasis of primary adrenocortical carcinoma with adjuvant mitotane plus transcatheter arterial chemoembolization and microwave ablation: a case report

Adrenocortical carcinoma (ACC) is a rare, heterogeneous, and aggressive malignancy with a generally poor prognosis. Surgical resection is the optimal treatment plan. After surgery, both mitotane treatment or the etoposide-doxorubicin-cisplatin (EDP) protocol plus mitotane chemotherapy have a certain effect, but there is still an extremely high possibility of recurrence and metastasis. The liver is one of the most common metastatic targets. Therefore, techniques such as transcatheter arterial chemoembolization (TACE) and microwave ablation (MWA) for liver tumors can be attempted in a specific group of patients. We present the case of a 44-year-old female patient with primary ACC, who was diagnosed with liver metastasis 6 years after resection. During mitotane treatment, we performed four courses of TACE and two MWA procedures in accordance with her clinical condition. The patient has maintained the partial response status and has currently returned to normal life to date. This case illustrates the value of the practical application of mitotane plus TACE and MWA treatment.

Adrenocortical Carcinoma: Role of Adjuvant and Neoadjuvant Therapy

Adjuvant and neoadjuvant chemotherapy in the treatment of adrenocortical carcinoma (ACC) is limited by few existing trials, most of which are retrospective. The drug mitotane has been used for the treatment of ACC, although existing guidelines only support its use in high risk of recurrence. The first phase 3 trial involving systemic chemotherapy for ACC supports the use of etoposide, doxorubicin, cisplatin, and mitotane for combination therapy. No significant breakthrough has been discovered thus far in of targeted and immunotherapies. Neoadjuvant chemotherapy is only used to allow for complete surgical resection because complete excision is the definitive treatment of ACC.

The Characteristics of Tumor Microenvironment Predict Survival and Response to Immunotherapy in Adrenocortical Carcinomas

Increasing evidence confirms that tumor microenvironment (TME) can influence tumor progression and treatment, but TME is still understudied in adrenocortical carcinoma (ACC). In this study, we first scored TME using the xCell algorithm, then defined genes associated with TME, and then used consensus unsupervised clustering analysis to construct TME-related subtypes. Meanwhile, weighted gene co-expression network analysis was used to identify modules correlated with TME-related subtypes. Ultimately, the LASSO-Cox approach was used to establish a TME-related signature. The results showed that TME-related scores in ACC may not correlate with clinical features but do promote a better overall survival. Patients were classified into two TME-related subtypes. Subtype 2 had more immune signaling features, higher expression of immune checkpoints and MHC molecules, no CTNNB1 mutations, higher infiltration of macrophages and endothelial cells, lower tumor immune dysfunction and exclusion scores, and higher immunophenoscore, suggesting that subtype 2 may be more sensitive to immunotherapy. 231 modular genes highly relevant to TME-related subtypes were identified, and a 7-gene TME-related signature that independently predicted patient prognosis was established. Our study revealed an integrated role of TME in ACC and helped to identify those patients who really responded to immunotherapy, while providing new strategies on risk management and prognosis prediction.

A Systematic Review of Published Clinical Trials in the Systemic Treatment of Adrenocortical Carcinoma: An Initiative Led on Behalf of the Global Society of Rare Genitourinary Tumors

Adrenocortical carcinoma (ACC) is a very rare endocrine cancer and is associated with a poor prognosis. There is a paucity of randomized clinical trials for this rare disease. We aimed to perform a systematic review of the literature on systemic therapy options in different stages of ACC. A systematic review was performed using Pubmed and Embase databases according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. A total of 24 trials of systemic therapy in the treatment of ACC were identified and included in this review. Only one clinical trial in the adjuvant setting was identified, the negative phase III trial ADIUVO, which tested mitotane in low to intermediate-risk ACC patients. In the treatment of advanced ACC, cisplatin-based chemotherapy was evaluated in small and non-randomized phase II trials, and response rates ranged from 21% to 53.5%. The phase III trial FIRM-ACT compared etoposide, doxorubicin, cisplatin, and mitotane versus treatment with streptozotocin and mitotane and showed no difference in OS, but higher RR and PFS were reported with the multi-drug regimen. Six clinical trials of immunotherapy and seven studies of targeted therapy in advanced ACC were included, with modest activity and no phase 3 trials were identified. Treatment recommendations of ACC are based on retrospective and small studies with limited systemic therapy options. International and multi-center collaboration is essential to expand clinical research and improve outcomes.

The management of postoperative disease recurrence in patients with adrenocortical carcinoma: a retrospective study in 106 patients

OBJECTIVE

The management of adrenocortical carcinoma (ACC) recurrences remains controversial, and we present herein our experience with postoperative ACC recurrences.

DESIGN AND METHODS

Retrospective analysis in a single reference center of 106 patients with ACC recurrence.

RESULTS

The median follow-up was 45 months, the median recurrence-free survival (RFS) 12 months (IQR 6-23), and the median overall survival (OS) 45 months (IQR 29-75). ACC recurrences occurred as a unique lesion (group A) in 35.8%, multiple lesions in a single organ (group B) in 20.8%, and affecting multiple organs (group C) in 43.4% of patients. Baseline characteristics of patients stratified by the type of recurrence did not differ between them, except RFS, which was significantly longer in group A. Locoregional treatments were used in 100% of patients of group A, 68.2% in group B, and 26.1% in group C. After treatment of recurrence, 60.4% of patients became free of disease attaining a second RFS of 15 months (IQR 6-64). Margin status RX and R1, percent increase in Ki67, and recurrence in multiple organs were associated with an increased risk of mortality, while adjuvant mitotane treatment and longer time to first recurrence were associated with reduced risk. Recurrence in multiple organs and systemic treatment of recurrence had a negative impact on survival from the treatment of recurrence.

CONCLUSIONS

This study shows that patients with ACC have a better prognosis when the disease recurs as a single lesion and supports the use of locoregional treatments to treat disease recurrence.

Treatment of adrenocortical carcinoma: oncological and endocrine outcomes

PURPOSE OF REVIEW

Adrenocortical carcinoma (ACC) is a rare, aggressive disease with a paucity of data and great variability between published studies regarding its treatment. This review provides information on current clinical management and oncological and endocrine outcomes.

RECENT FINDINGS

Complete surgical resection is the only potentially curative treatment for adrenocortical carcinoma (ACC). Adjuvant mitotane treatment is recommended in patients with favourable/intermediate prognosis. As part of the endocrine follow-up, steroid hormones and thyroid hormones may be decreased or increased and may need to be substituted or suppressed. Recurrences are common. If the disease-free interval is more than 12 months, surgery is a treatment if complete resection is feasible. In advanced/metastatic ACC patients, the prognosis is poor. Mitotane monotherapy is only appropriate for patients with low tumour burden and indolent disease. Patients with unfavourable prognosis should be treated with aggressive cytotoxic therapy. Patients requiring third-line treatment should be considered for clinical trials. Immunotherapy and targeted therapy are currently being investigated, but have so far yielded only unsatisfactory results.

SUMMARY

There is scarce evidence for the treatment of ACC, which often complicates clinical decision-making. Patients who progress on EDP-M should be treated in clinical trials.

Effects of o,p'-DDE, a Mitotane Metabolite, in an Adrenocortical Carcinoma Cell Line

In South Brazil, the incidence of pediatric adrenocortical carcinoma (ACC) is higher than in other regions and countries worldwide. The ACC treatment includes therapy with mitotane, the only adrenolytic drug approved by the FDA. The mitotane metabolism occurs via two main reactions: the β-hydroxylation, which yields the final product o,p'-DDA, and the α-hydroxylation, which will give the final product o,p'-DDE. It is speculated that o,p'-DDE may be an active metabolite since it has a cytotoxic effect on adrenocortical carcinoma cells (H295R). No further studies have been conducted to confirm this hypothesis; however, it was found that mitotane and its metabolites are present at significantly different concentrations in the plasma of the patients. Our study aimed to assess the in vitro effects of o,p'-DDE and o,p'-DDD in cell death pathways, oxidative parameters, and interaction with adrenal CYP's involved in the steroidogenic process in the H295R cell line. It was found that o,p'-DDE had a different effect than the o,p'-DDD on apoptosis, inhibiting this cell death pathway, but it promotes cell necrosis at higher concentrations. In contrast to o,p'-DDD, the o,p'-DDE did not have effects on the different oxidative parameters evaluated, but exhibited stimulatory interactions with steroidogenic CYP's, at intermediate concentrations. Therefore, we demonstrated important cell effects of o,p'-DDE; its plasma levels during mitotane therapy should be monitored as an important therapeutic parameter.

Low-dose mitotane-induced neurological and endocrinological complication in a 5-year-old girl with adrenocortical carcinoma

Mitotane is an adrenolytic drug that exhibits therapeutic effects within a narrow target range (14-20 μg/dL). Various complications develop if the upper limit is exceeded. We present the case of a 5-year-old girl with breast development, acne, and pubic hair who was diagnosed with an adrenal mass that was subsequently excised. The pathological finding was adrenocortical carcinoma with a high risk of malignancy, and adjuvant therapy (combined mitotane and radiation therapy) was recommended. Mitotane was initiated at a low dose to allow monitoring of the therapeutic drug level, and high-dose hydrocortisone was also administered. However, the patient exhibited elevated adrenocorticotropic hormone levels and vague symptoms such as general weakness and difficulty concentrating. It was important to determine if these symptoms were signs of the neurological complications that develop when mitotane level is elevated. Encephalopathy progression and pubertal signs appeared 6 months after diagnosis, induced by high mitotane level. The mitotane decreased to subtherapeutic level several months after its discontinuation, at which time endocrinopathy (central hypothyroidism, hypercholesterolemia, and secondary central precocious puberty) developed. The case shows that low-dose mitotane can trigger neurological and endocrinological complications in a pediatric patient, indicating that the drug dose should be individualized with frequent monitoring of the therapeutic level.

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.

Massive adrenocortical carcinoma presenting as peripheral edema: a case report

Background

Adrenocortical carcinoma is a rare, but potentially lethal, malignancy that is usually detected as an incidental finding on abdominal imaging studies or owing to hormonal complications. This report recounts an unusual presentation with leg edema due to compression of the inferior vena cava. The dearth of proven effective treatment is also addressed.

Case presentation

A 65-year-old White male physician presented with severe, bilateral pitting edema that extended from the toes to the thighs. It progressed over several months. He also experienced paroxysmal dyspnea. Evaluation of cardiac, hepatic, and renal function failed to determine a cause. Computed tomography revealed a tumor above the right kidney, with compression of the intrahepatic inferior vena cava and upstream distension. Serum cortisol and dehydroepiandrosterone sulfate concentrations were elevated, 24-hour urinary cortisol level was elevated, and serum adrenocorticotropic hormone and testosterone concentrations were suppressed. A 27-cm tumor, the right lobe of the liver, the right kidney, and 26 lymph nodes were resected. Histological study confirmed the diagnosis of adrenocortical carcinoma. Ki67 proliferation index was 26.7% (worse prognosis associated with index > 10%). Lymph nodes were negative for malignancy, but a separate 2.7-cm tumor was found near the renal hilum. Adjuvant mitotane chemotherapy was prescribed. Serum testosterone concentration returned to normal. High-dose hydrocortisone administration was needed because of adrenal suppression and CYP 3A4 induction by mitotane.

Conclusion

Imaging of the abdomen and pelvis should be conducted in cases of unexplained leg edema. In this case, a large adrenal cancer compressed the vena cava. Iron deficiency followed resection of the large tumor. Advanced stages of adrenocortical carcinoma are associated with poor prognosis. Mitotane chemotherapy is a standard but unproven adjuvant treatment that is associated with many complications, and its induction of hepatic CYP 3A4 enzymes necessitates adjustment of other medications.

Mitotane treatment in adrenocortical carcinoma: mechanisms of action and predictive markers of response to therapy

INTRODUCTION

Adrenocortical carcinoma (ACC) is a rare malignancy with a high risk of recurrence even in cases with complete surgical tumor resection. Mitotane represents the cornerstone of the adjuvant therapy as well as the first line of medical treatment in advanced cases. However, evidence on mitotane efficacy is mostly based on retrospective studies and the use of mitotane continues to represent a clinical challenge.

EVIDENCE ACQUISITION

Mitotane causes selective damage to adrenocortical cells, causing an increase of cell apoptosis through a disruption of mitochondria and the induction of the endoplasmic reticulum stress. Different clinical and molecular markers predicting response to mitotane have been proposed with uncertain results. Attainment of mitotane plasma levels within the target range of 14 to 20 mg/L represent the strongest predictor of mitotane effectiveness both in adjuvant and advanced tumor setting. The occurrence of late recurrence after primary ACC diagnosis and changes in metabolic activity on FDG-PET are only weakly associated with mitotane response. Among the proposed molecular markers associated with mitotane efficacy, the investigation of the CYP2W1*6 and CYP2B6*6 single nucleotide polymorphisms appears to be currently the most promising predictive molecular markers of mitotane therapy. However, none of the evaluated markers has been validated for clinical use.

CONCLUSIONS

In the era of precision medicine, a better insight into mitotane molecular mechanisms as well as the potential use in the daily clinical practice of clinical parameters and molecular markers predicting the individual response to mitotane are urgently needed.

High TNFSF13B expression as a predictor of poor prognosis in adrenocortical carcinoma

Background

Adrenocortical carcinoma (ACC) is an extremely rare malignant tumor with poor prognosis. Existing treatment options have limited effects, and new therapeutic targets urgently need to be discovered. TNFSF13B has been reported to be associated with the prognosis of clear cell renal cell carcinoma, but it has not been studied in ACC.

Methods

TNFSF13B expression was analyzed and compared between ACC tumors and normal tissues by using public datasets from TCGA and GTEx. Kaplan-Meier analysis was employed to evaluate survival, and Cox regression was employed to evaluate clinicopathologic features. The upstream and downstream regulatory mechanisms of TNFSF13B were also analyzed. GSEA was performed to explore the mechanisms of TNFSF13B in ACC. Finally, 14 ACC clinical samples were used to verify the relationships between TNFSF13B expression and disease-free survival (DFS) and overall survival (OS).

Results

TNFSF13B expression was significantly higher in ACC tissues than in normal tissues. The prognosis of ACC patients with high TNFSF13B expression was worse than that of patients with low TNFSF13B expression. High TNFSF13B expression was strongly correlated with poor prognosis, and TNFSF13B was a prognostic factor. TNFSF13B expression is modified by upstream miRNAs, methylation and ubiquitination, and downstream, it interacts with other proteins. GSEA showed that regulation of cholesterol biosynthesis by SREBP and SREBF, downstream signaling events of the B cell receptor (BCR) and activation of gene expression by SREBF and SREBP were significantly enriched in the TNFSF13B high-expression phenotype. Clinical samples confirmed that TNFSF13B expression was significantly associated with DFS but not with OS.

Conclusions

TNFSF13B may be a potential prognostic molecular marker of poor survival in ACC patients, offering a new therapeutic target.

Management of adrenocortical carcinoma: are we making progress?

Adrenocortical carcinoma (ACC) is a rare malignancy characterized by aggressive biology and potential endocrine activity. Surgery can offer cure for localized disease but more than half of patients relapse and primary unresectable or metastasized disease is frequent. Prognosis of metastatic ACC is still limited, with less than 15% of patients alive at 5 years. Recent advances in understanding the molecular profile of ACC underline the high complexity of this disease, which is characterized by limited drugable molecular targets as well as by a complex interplay between a yet scarcely understood microenvironment and potential endocrine activity. Particularly steroid-excess further complicates therapeutic concepts such as immunotherapy, which have markedly improved outcome in other disease entities. To date, mitotane remains the only approved drug for adjuvant and palliative care in ACC. Standard chemotherapy-based protocols with cisplatin, doxorubicin and etoposide offer only marginal improvement in long-term outcome and the number of clinical trials conducted is low due to the rarity of the disease. In the current review, we summarize principles of oncological management for ACC from localized to advanced disease and discuss novel therapeutic strategies, including targeted therapies such as tyrosine kinase inhibitors and antibodies, immunotherapy with a focus on checkpoint inhibitors, individualized treatment concepts based on molecular characterization by next generation sequencing methods, the role of theranostics and evolvement of adjuvant therapy.

Impact of postoperative radiotherapy on the outcomes of resected adrenocortical carcinoma-a real-world, population-based study

OBJECTIVE

To assess the impact of postoperative radiotherapy on the outcomes of resected adrenocortical carcinoma in a real-world setting.

METHODS

The Surveillance, Epidemiology, and End Results Research Plus database was accessed, and patients with resected non-metastatic adrenocortical carcinoma diagnosed 2010-2015 were reviewed. Kaplan-Meier estimates and log-rank testing were used to examine the impact of postoperative radiotherapy on overall and cancer-specific survival. Multivariable Cox regression analysis was used to explore factors associated with overall and cancer-specific survival.

RESULTS

A total of 294 patients were included in the final analysis, including 60 patients (20.4%) who received postoperative radiotherapy. Using Kaplan-Meier estimates, individuals who received postoperative radiotherapy have better overall survival (P = 0.002). Multivariable cox regression analysis showed that the following factors were associated with worse overall survival: older age (HR: 1.01; 95% CI: 1.00-1.03), male sex (HR for female sex versus male sex: 0.61; 95% CI: 0.43-0.85), and non-receipt of postoperative radiation therapy (HR: 2.29; 95% CI: 1.38-3.77). Systemic therapy was not associated with differences in overall survival (HR: 0.77; 95% CI: 0.54-1.10). Likewise, the following factors were associated with worse cancer-specific survival: male sex (HR for female sex versus male sex: 0.60; 95% CI: 0.41-0.88), non-receipt of postoperative radiation therapy (HR: 2.17; 95% CI: 1.27-3.70), and receipt of perioperative systemic therapy (HR: 0.67; 95% CI: 0.45-0.99).

CONCLUSION

Postoperative radiotherapy following resection of adrenocortical carcinoma is associated with better overall and cancer-specific survival.

Neuroendocrine and Adrenal Tumors, Version 2.2021, NCCN Clinical Practice Guidelines in Oncology

The NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Neuroendocrine and Adrenal Gland Tumors focus on the diagnosis, treatment, and management of patients with neuroendocrine tumors (NETs), adrenal tumors, pheochromocytomas, paragangliomas, and multiple endocrine neoplasia. NETs are generally subclassified by site of origin, stage, and histologic characteristics. Appropriate diagnosis and treatment of NETs often involves collaboration between specialists in multiple disciplines, using specific biochemical, radiologic, and surgical methods. Specialists include pathologists, endocrinologists, radiologists (including nuclear medicine specialists), and medical, radiation, and surgical oncologists. These guidelines discuss the diagnosis and management of both sporadic and hereditary neuroendocrine and adrenal tumors and are intended to assist with clinical decision-making. This article is focused on the 2021 NCCN Guidelines principles of genetic risk assessment and counseling and recommendations for well-differentiated grade 3 NETs, poorly differentiated neuroendocrine carcinomas, adrenal tumors, pheochromocytomas, and paragangliomas.

What Is the Optimal Duration of Adjuvant Mitotane Therapy in Adrenocortical Carcinoma? An Unanswered Question

A relevant issue on the treatment of adrenocortical carcinoma (ACC) concerns the optimal duration of adjuvant mitotane treatment. We tried to address this question, assessing whether a correlation exists between the duration of adjuvant mitotane treatment and recurrence-free survival (RFS) of patients with ACC. We conducted a multicenter retrospective analysis on 154 ACC patients treated for ≥12 months with adjuvant mitotane after radical surgery and who were free of disease at the mitotane stop. During a median follow-up of 38 months, 19 patients (12.3%) experienced recurrence. We calculated the RFS after mitotane (RFSAM), from the landmark time-point of mitotane discontinuation, to overcome immortal time bias. We found a wide variability in the duration of adjuvant mitotane treatment among different centers and also among patients cared for at the same center, reflecting heterogeneous practice. We did not find any survival advantage in patients treated for longer than 24 months. Moreover, the relationship between treatment duration and the frequency of ACC recurrence was not linear after stratifying our patients in tertiles of length of adjuvant treatment. In conclusion, the present findings do not support the concept that extending adjuvant mitotane treatment over two years is beneficial for ACC patients with low to moderate risk of recurrence.

Pharmacological profile and effects of mitotane in adrenocortical carcinoma

Mitotane is the only adrenolytic drug approved by the Food and Drug Administration for treating adrenocortical carcinoma (ACC). This drug has cytotoxic effects on tumour tissues; it induces cell death and antisecretory effects on adrenal cells by inhibiting the synthesis of adrenocortical steroids, which are involved in the pathogenesis of ACC. However, high doses of mitotane are usually necessary to reach the therapeutic plasma concentration, which may result in several adverse effects. This suggests that important pharmacological processes, such as first pass metabolism, tissue accumulation and extensive time for drug elimination, are associated with mitotane administration. Few studies have reported the pharmacological aspects and therapeutic effects of mitotane. Therefore, the aim of this review was to summarize the chemistry, pharmacokinetics and pharmacodynamics, and therapeutic and toxic effects of mitotane. This review also discusses new perspectives of mitotane formulation that are currently under investigation. Understanding the pharmacological profile of mitotane can improve the monitoring and efficacy of this drug in ACC treatment and can provide useful information for the development of new drugs with specific action against ACC with fewer adverse effects.

Medical Approaches in Adrenocortical Carcinoma

Adrenocortical carcinoma (ACC) represents one of the most aggressive endocrine tumors. In spite of a correct therapeutic strategy based on a multidisciplinary approach between endocrinologist, surgeon and oncologist, the prognosis is often poor. Surgery is the mainstay treatment in ACC. Mitotane, a dichloro-diphenyl-trichloro-ethane derivate, represents the main medical treatment of ACC in consideration of its adrenocytolitic activity and it is mainly employed as adjuvant treatment after complete surgical resection and for the treatment of advanced ACC. However, the use of mitotane as adjuvant therapy is still controversial, also in consideration of the retrospective nature of several studies. The recurrence of disease is frequent, especially in advanced disease at the diagnosis. Therefore, in these contexts, conventional chemotherapy must be considered in association with mitotane, being the combination etoposide, doxorubicin and cisplatin (EDP) the standard of care in this setting. A more modern therapeutic approach, based on the need of a salvage therapy for advanced ACC that progresses through first-line EDP, is focused on molecular-targeted therapies. However, robust clinical trials are necessary to assess the real efficacy of these treatments.

Analysis of adjuvant chemotherapy in patients undergoing curative-intent resection of localized adrenocortical carcinoma

BACKGROUND

Studies evaluating the role of adjuvant chemotherapy (ACT) in Adrenocortical Carcinoma (ACC) are limited due to its rarity. The objective of this study was to evaluate if ACT provides a survival benefit in patients who underwent curative-intent resection of localized ACC and to determine factors associated with receipt of ACT.

METHODS

The National Cancer Data Base was queried to identify patients (2010-2016) with curative-intent resection of localized ACC (T1-T3, N0, M0).

RESULTS

Of 577 patients with adrenalectomy, 389 (67%) had adrenalectomy alone, and 188 (33%) received ACT. Private insurance, lymphovascular invasion, stage II, and radiotherapy were predictors of ACT (P < 0.05). Advanced (T3) stage lymphovascular invasion, and being uninsured were associated with decreased OS (P < 0.05). There was no association between ACT and OS.

CONCLUSIONS

For patient who underwent curative-intent resection of localized ACC, there was no association between ACT and OS. Private insurance, lymphovascular invasion, stage II disease, and radiotherapy were associated with receipt of ACT.

Expression of FSCN1 and FOXM1 are associated with poor prognosis of adrenocortical carcinoma patients

Background

Adrenocortical carcinoma (ACC) is a rare malignant endocrine tumour. Due to a high tumour recurrence rate, the post-operative overall survival (OS) and disease-free survival (DFS) of ACCs is limited. Our research aims to identify the role of the epithelial-mesenchymal transition (EMT) related genes FSCN1 and FOXM1 in the tumour microenvironment and assess their prognostic value in ACCs.

Methods

Clinical and specimen data from 130 adrenocortical carcinoma (ACC) patients was acquired from the Cancer Genome Atlas (TCGA) database (n = 79) and a West China Hospital (WCH) cohort (n = 51). In the WCH cohort, archived formalin-fixed paraffin embedded (FFPE) samples were collected for immunohistochemical analysis. The correlation between the EMT genes and the tumour microenvironment status was estimated based on the Tumour Immune Estimation Resource (TIMER) algorithm. Kaplan-Meier analysis, followed by univariate and multivariate regression analyses, were performed to identify the prognostic association of FSCN1 and FOXM1.

Results

FSCN1 and FOXM1 were over-expressed in ACC tissue when compared with adrenocortical adenoma and normal adrenal tissue. Over-expression of FSCN1 or FOXM1 was associated with the tumour microenvironment and immune signatures in ACCs. Patients with higher expression of FSCN1 or FOXM1 were more likely to have worse prognoses. The prognostic effects were further verified in both early (stage I/II) and advanced (stage III/IV) ACCs. Furthermore, FSCN1 and FOXM1 appeared as independent prognostic factors in ACC.

Conclusions

These results show that FSCN1 and FOXM1 are independent prognostic factors in ACCs and over-expression of FSCN1 or FOXM1 indicates a worse prognosis.

Management of Adrenocortical Carcinoma

PURPOSE OF REVIEW

Adrenocortical carcinoma (ACC) is a rare endocrine malignancy typically with poor prognosis. This review aims to summarize the current knowledge regarding the clinical management of ACC.

RECENT FINDINGS

Surgery remains the cornerstone for localized ACC management. In more advanced cases, debulking surgery when feasible can help with hormonal control and may allow the initiation of systemic therapy. Over the last few years, our understanding of ACC molecular pathogenesis has expanded with no significant change in treatment options. Platinum-based chemotherapy is the gold standard in metastatic ACC despite suboptimal efficacy. Tyrosine kinase inhibitor use did not result in meaningful benefit in ACC patients. Multiple clinical trials are currently exploring the role of immunotherapy in ACC. Despite the remarkable improvement in our understanding of the molecular signature and pathways in ACC, this knowledge did not yield a major breakthrough in management of advanced ACC. Multi-institutional and international collaborations are needed to identify promising treatments and new therapeutic targets to improve the care of ACC patients.