Adjuvant mitotane therapy is beneficial in non-metastatic adrenocortical carcinoma at high risk of recurrence

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.

Adjuvant mitotane versus surveillance in low-grade, localised adrenocortical carcinoma (ADIUVO): an international, multicentre, open-label, randomised, phase 3 trial and observational study

BACKGROUND

Adjuvant treatment with mitotane is commonly used after resection of adrenocortical carcinoma; however, treatment remains controversial, particularly if risk of recurrence is not high. We aimed to assess the efficacy and safety of adjuvant mitotane compared with surveillance alone following complete tumour resection in patients with adrenocortical carcinoma considered to be at low to intermediate risk of recurrence.

METHODS

ADIUVO was a multicentre, open-label, parallel, randomised, phase 3 trial done in 23 centres across seven countries. Patients aged 18 years or older with adrenocortical carcinoma and low to intermediate risk of recurrence (R0, stage I-III, and Ki67 ≤10%) were randomly assigned to adjuvant oral mitotane two or three times daily (the dose was adjusted by the local investigator with the target of reaching and maintaining plasma mitotane concentrations of 14-20 mg/L) for 2 years or surveillance alone. All consecutive patients at 14 study centres fulfilling the eligibility criteria of the ADIUVO trial who refused randomisation and agreed on data collection via the European Network for the Study of Adrenal Tumors adrenocortical carcinoma registry were included prospectively in the ADIUVO Observational study. The primary endpoint was recurrence-free survival, defined as the time from randomisation to the first radiological evidence of recurrence or death from any cause (whichever occurred first), assessed in all randomly assigned patients by intention to treat. Overall survival, defined as time from the date of randomisation to the date of death from any cause, was a secondary endpoint analysed by intention to treat in all randomly assigned patients. Safety was assessed in all patients who adhered to the assigned regimen, which was defined by taking at least one tablet of mitotane in the mitotane group and no mitotane at all in the surveillance group. The ADIUVO trial is registered with ClinicalTrials.gov, NCT00777244, and is now complete.

FINDINGS

Between Oct 23, 2008, and Dec 27, 2018, 45 patients were randomly assigned to mitotane and 46 to surveillance alone. Because the study was discontinued prematurely, 5-year recurrence-free and overall survival are reported instead of recurrence-free and overall survival as defined in the protocol. 5-year recurrence-free survival was 79% (95% CI 67-94) in the mitotane group and 75% (63-90) in the surveillance group (hazard ratio 0·74 [95% CI 0·30-1·85]). Two people in the mitotane group and five people in the surveillance group died, and 5-year overall survival was not significantly different (95% [95% CI 89-100] in the mitotane group and 86% [74-100] in the surveillance group). All 42 patients who received mitotane had adverse events, and eight (19%) discontinued treatment. There were no grade 4 adverse events or treatment-related deaths.

INTERPRETATION

Adjuvant mitotane might not be indicated in patients with low-grade, localised adrenocortical carcinoma considering the relatively good prognosis of these patients, and no significant improvement in recurrence-free survival and treatment-associated toxicity in the mitotane group. However, the study was discontinued prematurely due to slow recruitment and cannot rule out an efficacy of treatment.

FUNDING

AIFA, ENSAT Cancer Health F2-2010-259735 programme, Deutsche Forschungsgemeinschaft, Cancer Research UK, and the French Ministry of Health.

New Findings on Presentation and Outcome of Patients With Adrenocortical Cancer: Results From a National Cohort Study

CONTEXT

Because of the rarity of adrenocortical cancer (ACC), only a few population-based studies are available, and they reported limited details in the characterization of patients and their treatment.

OBJECTIVE

To describe in a nationwide cohort the presentation of patients with ACC, treatment strategies, and potential prognostic factors.

METHODS

Retrospective analysis of 512 patients with ACC, diagnosed in 12 referral centers in Italy from January 1990 to June 2018.

RESULTS

ACC diagnosed as incidentalomas accounted for overall 38.1% of cases, with a frequency that increases with age and with less aggressive pathological features than symptomatic tumors. Women (60.2%) were younger than men and had smaller tumors, which more frequently secreted hormones. Surgery was mainly done with an open approach (72%), and after surgical resection, 62.7% of patients started adjuvant mitotane therapy. Recurrence after tumor resection occurred in 56.2% of patients. In patients with localized disease, cortisol secretion, ENSAT stage III, Ki67%, and Weiss score were associated with an increased risk of recurrence, whereas margin-free resection, open surgery, and adjuvant mitotane treatment were associated with reduced risk. Death occurred in 38.1% of patients and recurrence-free survival (RFS) predicted overall survival (OS). In localized disease, age, cortisol secretion, Ki67%, ENSAT stage III, and recurrence were associated with increased risk of mortality. ACCs presenting as adrenal incidentalomas showed prolonged RFS and OS.

CONCLUSION

Our study shows that ACC is a sex-related disease and demonstrates that an incidental presentation is associated with a better outcome. Given the correlation between RFS and OS, RFS may be used as a surrogate endpoint in clinical studies.

Pregnancy in patients with adrenocortical carcinoma: a case-based discussion

Although adrenocortical carcinoma (ACC) during pregnancy is rare, a retrospective review of a case series at our hospital revealed that almost one third of our patients were women in childbearing age. Given that the age of maternity is increasing, dealing with a tumor diagnosis during pregnancy and the need for fertility planning in cancer survivors is likely to become more frequent.We thus carried out a case-based discussion regarding: i) diagnosing and treating an ACC during pregnancy; ii) patients conceiving while on mitotane; iii) ACC survivors with a maternal desire.In each of these cases, it is important to provide patients with sufficient information, to offer medical advice and psychological support, to personalize treatments in accordance with the wishes of the patient and her relatives, and to collaborate with other specialists since a multidisciplinary expert team is required to manage each case individually.

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.

Sexually dimorphic activation of innate antitumor immunity prevents adrenocortical carcinoma development

Unlike most cancers, adrenocortical carcinomas (ACCs) are more frequent in women than in men, but the underlying mechanisms of this sexual dimorphism remain elusive. Here, we show that inactivation of Znrf3 in the mouse adrenal cortex, recapitulating the most frequent alteration in ACC patients, is associated with sexually dimorphic tumor progression. Although female knockouts develop metastatic carcinomas at 18 months, adrenal hyperplasia regresses in male knockouts. This male-specific phenotype is associated with androgen-dependent induction of senescence, recruitment, and differentiation of highly phagocytic macrophages that clear out senescent cells. In contrast, in females, macrophage recruitment is delayed and dampened, which allows for aggressive tumor progression. Consistently, analysis of TCGA-ACC data shows that phagocytic macrophages are more prominent in men and are associated with better prognosis. Together, these data show that phagocytic macrophages are key players in the sexual dimorphism of ACC that could be previously unidentified allies in the fight against this devastating cancer.

ENDOCRINE TUMOURS: Our experience with the management of patients with non-metastatic adrenocortical carcinoma

Adrenocortical carcinoma (ACC) accounts for a minority of all malignant tumors in adults. Surgery remains the most important therapeutic option for non-metastatic ACC. Whether a subset of patients with small ACC may benefit from minimally invasive surgery remains a debated issue, but we believe that surgeon's expertise is more important than surgical technique to determine outcome. However, even a state-of-the-art surgery cannot prevent disease recurrence that is determined mainly by specific tumor characteristics. We consider that the concomitant presence of the following features characterizes a cohort of patients at low risk of recurrence, (i) R0 resection (microscopically free margin), (ii) localized disease (stage I-II ACC), and (iii) low-grade tumor (ki-67 <10%). After the ADIUVO study, we do not recommend adjuvant mitotane as a routine measure for such patients, who can be managed with active surveillance thus sparing a toxic treatment. Patients at average risk of recurrence should be treated with adjuvant mitotane. For patients at very high risk of recurrence, defined as the presence of at least one of the following: Ki67 >30%, large venous tumor thrombus, R1 resection or stage IV ACC, we increasingly recommend to combine mitotane with four cycles of platinum-based chemotherapy. However, patients at moderate-to-high risk of recurrence should be ideally enrolled in the ongoing ADIUVO2 trial. We do not use adjuvant radiotherapy of the tumor bed frequently at our institutions, and we select patients with incomplete resection, either microscopically or macroscopically, for this treatment. In the long-term, prospective multicenter trials are required to improve patient care.

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.

S-GRAS score performs better than a model from SEER for patients with adrenocortical carcinoma

PURPOSE

To externally validate the performance of the S-GRAS score and a model from the Surveillance, Epidemiology, and End Results (SEER) database in a Chinese cohort of patients with adrenocortical carcinoma (ACC).

METHODS

We first developed a model using data from the SEER database, after which we retrospectively reviewed 51 ACC patients hospitalized between 2013 and 2018, and we finally validated the model and S-GRAS score in this Chinese cohort.

RESULTS

Patient age at diagnosis, tumor size, TNM stage, and radiotherapy were used to construct the model, and the Harrell's C-index of the model in the training set was 0.725 (95% CI: 0.682-0.768). However, the 5-year area under the curve (AUC) of the model in the validation cohort was 0.598 (95% CI: 0.487-0.708). The 5-year AUC of the ENSAT stage was 0.640 (95% CI: 0.543-0.737), but the Kaplan-Meier curves of stages I and II overlapped in the validation cohort. The resection status (P = 0.066), age (P=0.68), Ki67 (P = 0.69), and symptoms (P = 0.66) did not have a significant impact on cancer-specific survival in the validation cohort. In contrast, the S-GRAS score group showed better discrimination (5-year AUC: 0.683, 95% CI: 0.602-0.764) than the SEER model or the ENSAT stage.

CONCLUSION

The SEER model showed favorable discrimination and calibration ability in the training set, but it failed to distinguish patients with various prognoses in our institution. In contrast, the S-GRAS score could effectively stratify patients with different outcomes.

Adjuvant therapy in adrenocortical carcinoma: prognostic factors and treatment options

Adrenocortical carcinoma (ACC) is a rare cancer with high recurrence rates and heterogeneous clinical behavior. The role of adjuvant therapy remains unclear because of the challenges in collecting high-quality data for a rare cancer. The current treatment recommendations and guidelines for adjuvant therapy are mostly derived retrospectively from national databases and the treatment outcomes of patients seen in referral centers. To better select patients for adjuvant therapy, multiple factors need to be considered including staging, markers of cellular proliferation (such as Ki67%), resection margins, hormonal function, and possibly genetic alterations of the tumor as well as patient-related factors such as age and performance status. Adjuvant mitotane remains the most commonly used adjuvant therapy in ACC based on clinical practice guidelines, though emerging data from ADIUVO trial (mitotane vs observation in low-risk ACC) suggest that mitotane use in low-risk patients may not be needed. An ongoing clinical trial (ADIUVO-2) is evaluating the role of mitotane vs mitotane combined with chemotherapy in high-risk ACC. The use of adjuvant therapy has been controversial but can be justified in select patients with positive resection margins or after the resection of localized recurrence. A prospective study is needed to study the role of adjuvant radiation in ACC as radiation is expected to help only with local control without impact on distant microscopic metastases. There are no recommendations or published data about using adjuvant immunotherapy in ACC, but this may be a future study after establishing the efficacy and safety profile of immunotherapy in metastatic ACC.

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.

S-GRAS score for prognostic classification of adrenocortical carcinoma: an international, multicenter ENSAT study

OBJECTIVE

Adrenocortical carcinoma (ACC) has an aggressive but variable clinical course. Prognostic stratification based on the European Network for the Study of Adrenal Tumours stage and Ki67 index is limited. We aimed to demonstrate the prognostic role of a points-based score (S-GRAS) in a large cohort of patients with ACC.

DESIGN

This is a multicentre, retrospective study on ACC patients who underwent adrenalectomy.

METHODS

The S-GRAS score was calculated as a sum of the following points: tumour stage (1-2 = 0; 3 = 1; 4 = 2), grade (Ki67 index 0-9% = 0; 10-19% = 1; ≥20% = 2 points), resection status (R0 = 0; RX = 1; R1 = 2; R2 = 3), age (<50 years = 0; ≥50 years = 1), symptoms (no = 0; yes = 1), and categorised, generating four groups (0-1, 2-3, 4-5, and 6-9). Endpoints were progression-free survival (PFS) and disease-specific survival (DSS). The discriminative performance of S-GRAS and its components was tested by Harrell's Concordance index (C-index) and Royston-Sauerbrei's R2D statistic.

RESULTS

We included 942 ACC patients. The S-GRAS score showed superior prognostic performance for both PFS and DSS, with best discrimination obtained using the individual scores (0-9) (C-index = 0.73, R2D = 0.30, and C-index = 0.79, R2D = 0.45, respectively, all P < 0.01vs each component). The superiority of S-GRAS score remained when comparing patients treated or not with adjuvant mitotane (n = 481 vs 314). In particular, the risk of recurrence was significantly reduced as a result of adjuvant mitotane only in patients with S-GRAS 4-5.

CONCLUSION

The prognostic performance of S-GRAS is superior to tumour stage and Ki67 in operated ACC patients, independently from adjuvant mitotane. S-GRAS score provides a new important guide for personalised management of ACC (i.e. radiological surveillance and adjuvant treatment).

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.

Adjuvant platinum-based chemotherapy in radically resected adrenocortical carcinoma: a cohort study

BACKGROUND

After radical resection, patients with adrenocortical carcinoma (ACC) frequently experience recurrence and, therefore, effective adjuvant treatment is urgently needed. The aim of the study was to investigate the role of adjuvant platinum-based therapy.

METHODS

In this retrospective multicentre cohort study, we identified patients treated with adjuvant platinum-based chemotherapy after radical resection and compared them with patients without adjuvant chemotherapy. Recurrence-free and overall survival (RFS/OS) were investigated in a matched group analysis and by applying a propensity score matching using the full control cohort (n = 268). For both approaches, we accounted for immortal time bias.

RESULTS

Of the 31 patients in the platinum cohort (R0 n = 25, RX n = 4, R1 n = 2; ENSAT Stage II n = 11, III n = 16, IV n = 4, median Ki67 30%, mitotane n = 28), 14 experienced recurrence compared to 29 of 31 matched controls (median RFS after the landmark at 3 months 17.3 vs. 7.3 months; adjusted HR 0.19 (95% CI 0.09-0.42; P < 0.001). Using propensity score matching, the HR for RFS was 0.45 (0.29-0.89, P = 0.021) and for OS 0.25 (0.09-0.69; P = 0.007).

CONCLUSIONS

Our study provides the first evidence that adjuvant platinum-based chemotherapy may be associated with prolonged recurrence-free and overall survival in patients with ACC and a very high risk for recurrence.

Adrenocortical carcinoma: current treatment options

PURPOSE OF REVIEW

In this article, we focus on the current and future treatment options for adrenocortical carcinoma (ACC).

RECENT FINDINGS

Radical surgery remains the only curative treatment for ACC. Recent reports showed a longer overall survival (OS) in patients with high risk of recurrence treated with adjuvant mitotane; the time in target range (14-20 mg/l) is related to low risk of relapse both in adjuvant and in palliative setting. In patients who experience disease progression after etoposide, doxorubicin, cisplatin with mitotane (EDP-M), gemcitabine and metronomic capecitabine, or the less used streptozotocin, represent a second-line chemotherapy option. Temozolomide can be employed as a third-line chemotherapy. To date, unsatisfactory results have been obtained on the efficacy of targeted therapies. Clinical trials are ongoing to evaluate the efficacy of tyrosine kinase and immune checkpoint inhibitors.

SUMMARY

ACC is a rare disease with a poor prognosis. The main therapy is represented by radical surgery conducted by an expert surgeon. Adjuvant mitotane has to be started in patients with high risk of recurrence. In patients with inoperable disease, the scheme EDP-M is the most employed. Few data are available on second-line and third-line chemotherapy in patients with disease progression after EDP-M. Currently, the role of targeted therapies is under evaluation.

Adrenocortical carcinoma: current state of the art, ongoing controversies, and future directions in diagnosis and treatment

Adrenocortical carcinoma (ACC) is a rare, aggressive malignancy with an annual incidence of ~1 case per million population. Differentiating between ACC and benign adrenocortical tumors can be challenging in patients who present with an incidentally discovered adrenal mass, due to the limited specificity of standard diagnostic imaging. Recently, urine steroid metabolite profiling has been prospectively validated as a novel diagnostic tool for the detection of malignancy with improved accuracy over current modalities. Surgery represents the only curative treatment for ACC, although local recurrence and metastases are common, even after a margin-negative resection is performed. Unlike other intra-abdominal cancers, the role of minimally invasive surgery and lymphadenectomy in ACC is controversial. Adjuvant therapy with the adrenolytic drug mitotane is used to reduce the risk of recurrence after surgery, although evidence supporting its efficacy is limited; it is also currently unclear whether all patients or a subset with the highest risk of recurrence should receive this treatment. Large-scale pan-genomic studies have yielded insights into the pathogenesis of ACC and have defined distinct molecular signatures associated with clinical outcomes that may be used to improve prognostication. For patients with advanced ACC, palliative combination chemotherapy with mitotane is the current standard of care; however, this is associated with poor response rates (RR). Knowledge from molecular profiling studies has been used to guide the development of novel targeted therapies; however, these have shown limited efficacy in early phase trials. As a result, there is an urgent unmet need for more effective therapies for patients with this devastating disease.

Approach to patients with European Network for the Study of Adrenal Tumor stages I and II adrenocortical carcinomas

PURPOSE OF REVIEW

Adrenocortical carcinoma (ACC) is a rare tumor with variable prognosis depending mostly on the disease stage and tumor grade. The staging system proposed by the European Network for the Study of Adrenal Tumors has a reliable prognostic potential and defines ACC stages I-IV. Due to the absence of extraadrenal tissue invasion, patients with stage I-II have a lower recurrence rate and better prognosis. This article elaborates on the current understanding of the clinical approach to this group of patients.

RECENT FINDINGS

Concerning the treatment, complete surgical resection of the tumor provides the only chance for cure. However, even after tumor removal, the risk of recurrence remains high and the main predictors of recurrence include tumor stage, grade (measured by Ki-67 proliferative index), and the tumor resection status. Adjuvant mitotane and/or adjuvant radiotherapy should be considered in patients with high risk of recurrence taking into account potential harmful effects of such treatment. Accordingly, careful selection of patients who may benefit from adjuvant treatment is of the utmost importance both for improving disease outcome and for avoiding potential overtreatment in patients who are at low risk of disease recurrence.

SUMMARY

Many aspects of the management of patients with ACC stages I and II are not entirely evidence-based, and treatment decisions rely mostly on expert opinions and data from retrospective studies. Therefore, the treatment of these patients should be restricted to specialized centers with high expertise in ACC.

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.

Sex Differences on Mitotane Concentration and Treatment Outcome in Patients with Adrenocortical Carcinoma

(1) Background: In clinical settings, data regarding sex are rarely investigated. In women, factors such as body size and composition, hormonal variations, metabolism, and access to care systems and therapy could strongly influence the pharmacological management and the outcome of the therapy. To underline this sex-related difference, we retrospectively collected data from adrenocortical carcinoma patients treated with mitotane, and then evaluated sex-related pharmacokinetics parameters. (2) Methods: A fully validated chromatographic method was used to quantify mitotane concentration in plasma collected from adult patients, also considering the active metabolite ortho,para,dichlorodiphenylethene (o,p'-DDE). Statistical analyses were used to evaluate the sex influence on drugs pharmacokinetics. (3) Results: We found that sex resulted as predictive factor of plasma mitotane and o,p'-DDE concentrations and significantly influenced the attainment of the therapeutic target of mitotane, implying that female sex could be a risk factor of treatment failure. (4) Conclusions: These results suggest that mitotane therapy should be modulated according to patient sex. Furthermore, the proposed approach could contribute to facilitating and disseminating sex-specific pharmacology.

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.

Open vs laparoscopic adrenalectomy for localized adrenocortical carcinoma

OBJECTIVE

The purpose of the study was to compare the long-term outcomes of patients with localized adrenocortical carcinoma (ACC) subjected to open vs laparoscopic surgery.

DESIGN

Retrospective study.

PATIENTS

This retrospective study included 46 patients with the ACC ENSAT stage I-stage III of whom 23 underwent open surgery (OA group), whereas 23 were subjected to laparoscopic adrenalectomy (LA group). The main outcomes analysed in the study were differences between the OA and LA groups in recurrence-free survival (RFS) and overall survival (OS).

RESULTS

Patients in OA group had larger tumours (120 [70-250] mm vs 75 [26-110] mm; P < .001), higher Ki-67 index (16 [1-65] % vs 10 [1-25] %; P = .04) and higher disease stage (P = .01) compared with the patients in the LA group. The median duration of follow-up for patients underwent OA and LA was 51 (12-174) and 53 (5-127) months, respectively. Eight patients (5 OA and 3 LA) experienced recurrent disease, whereas six patients (3 OA and 3 LA) died during follow-up. No differences in RFS and OS were found between patients who underwent open or laparoscopic surgery.

CONCLUSION

The study demonstrated that in patients with localized ACC and without invasion of extra-adrenal tissues, LA is a plausible treatment option in terms of RFS and OS. However, our results are limited to referral centres with large experience in the management of patients with ACC and may not necessarily apply to nonspecialized centres.

Unwanted Hormonal and Metabolic Effects of Postoperative Adjuvant Mitotane Treatment for Adrenocortical Cancer

Simple Summary

Mitotane is the only drug approved for treatment of adrenocortical cancer. Although mitotane is a derivative of the pesticide dichlorodiphenyltrichloroethane (DDT), limited data are available on its toxicity. Herein, we reported on the type and frequency of mitotane adverse events and on supportive therapies used to deal with toxicity in 74 mitotane-treated patients. Beyond the expected glucocorticoid insufficiency, a significant number of patients had a deficit of mineralocorticoid hormones, hypothyroid state and impaired testicular function, while fertile women frequently developed ovarian cysts during mitotane treatment. Multiple hormone replacement therapies were needed in >30% of patients. Statins were used in 50% of patients for significant hypercholesterolemia. Supportive therapies were able to revert the biochemical alterations, although higher doses were frequently used due to pharmacokinetic interactions with mitotane. Our study underlines the need of a careful and global approach to manage mitotane toxicity, to make adjuvant therapy safer and easier for patients.

Abstract

Mitotane is widely used for the treatment of adrenocortical cancer (ACC), although the drug-related toxicity complicates its use. The aim of this study is to assess comprehensively the different endocrine and metabolic unwanted effects of the drug, and to provide data on the supportive therapies. We retrospectively analyzed 74 ACC patients adjuvantly treated with mitotane for ≥12 months. During the treatment period (40 months, 12–195), 32.4% of patients needed replacement therapy for mineralocorticoid deficit, 36.2% for hypothyroidism and 34.3% for male hypogonadism. In fertile women, hypogonadism was uncommon, while 65.4% of women developed ovarian cysts. Although no significant change in low-density lipoprotein (LDL) was observed, statins were started in 50% of patients for a significant increase in total cholesterol and triglycerides. Dyslipidemia occurred early, after a median time of 6 months from mitotane start. Conversely, testosterone replacement was usually started after >2 years. In many cases, ranging from 29.4% to 50% according to the side effect, toxicity occurred well before the achievement of the target mitotane concentrations. Supportive therapies were able to revert the biochemical alterations induced by mitotane, although higher doses were needed for a likely pharmacokinetic interaction of exogenous steroids and statins with mitotane. In conclusion, adjuvant mitotane therapy is associated with a spectrum of unwanted effects encompassing the function of different endocrine glands and requires a careful clinical and biochemical assessment associated with the therapeutic drug monitoring.

New perspectives for mitotane treatment of adrenocortical carcinoma

Adrenocortical carcinoma (ACC) is an aggressive cancer characterized by poor survival. Apart from radical surgery, there is a limited range of therapeutic options and mitotane remains the cornerstone of medical treatment of ACC in either adjuvant or palliative settings. The aim of adjuvant mitotane therapy is to reduce the risk of ACC recurrence following surgical removal of the tumor. Use of mitotane in an adjuvant setting is off-label, but the recent guidelines endorsed by the European Society of Endocrinology (ESE) and the European Network for the Study of Adrenal Tumors (ENSAT) recommend it in ACC patients at high risk of recurrence. The palliative use of mitotane for treatment of advanced ACC aims at controlling tumor progression and, when present, hormone secretion. In this clinical setting, mitotane is used in association with chemotherapy to treat the more aggressive forms, while mitotane monotherapy is reserved for less progressive ACC. Many years after its introduction in clinical practice, there are still uncertainties surrounding the use of this old drug and the derived benefits. Moreover, physicians who use mitotane should recognize and manage the systemic effects of the drug that need a complex supporting therapy.

Involvement of 27-Hydroxycholesterol in Mitotane Action on Adrenocortical Carcinoma

Adrenocortical carcinoma (ACC) is a rare cancer with poor prognosis. Mitotane, the standard treatment for ACC, impairs adrenocortical steroid biosynthesis and cholesterol metabolism. In the H295R cell line, a standard ACC in vitro model, mitotane was previously reported to enhance the production of some oxysterols. To verify the possible mechanistic involvement of oxysterols in the anti-ACC effect of mitotane, a gas chromatography mass spectrometry (GC-MS) profiling of oxysterols and the main cholesterol precursors was carried out in H295R cells. Among the oxysterols detected in mitotane-treated cells, 27OHC was markedly produced, as well as lanosterol and lathosterol cholesterol precursors. In this cell model, mitotane was confirmed to affect mitochondrial transmembrane potential and induce apoptosis. Such cytotoxic effects were perfectly matched by H295R cell treatment with a single identical micromolar amount of 27OHC. The mitotane-dependent strong increase in 27OHC was confirmed in vivo, in the plasma of ACC patients under treatment with the drug. Moreover, lanosterol, lathosterol, desmosterol and, to a minor extent, 24-hydroxycholesterol and 25-hydroxycholesterol plasma levels were significantly increased in those patients. The cytotoxic effect of mitotane on ACC cells may be partly related to the increased intracellular level of 27OHC induced by the drug itself.

Adrenal cortical carcinoma: pathology, genomics, prognosis, imaging features, and mimics with impact on management

Adrenocortical carcinoma (ACC) is a rare tumor with a poor prognosis. Most tumors are either metastatic or locally invasive at the time of diagnosis. Differentiation between ACC and other adrenal masses depends on clinical, biochemical, and imaging factors. This review will discuss the genetics, pathological, and imaging feature of ACC.

Adjuvant Therapy in Adrenocortical Carcinoma: Reflections and Future Directions

Adrenocortical carcinoma (ACC) is a rare and aggressive malignancy with high risk of recurrence despite macroscopically complete surgical resection. The main predictors of ACC recurrence include advanced disease stage, incomplete surgical resection, cortisol production, certain genetic alterations, and high proliferation rate (Ki-67 proliferation index). Mitotane has been the mainstay adjuvant therapy of ACC. However, the use of mitotane is based on retrospective and occasionally conflicting evidence. As mitotane levels can take a few months before reaching therapeutic levels, there is an emerging practice of combining platinum-based chemotherapy with mitotane in the adjuvant setting. Retrospective data indicate that radiotherapy is an option for select patients, particularly those with positive resection margins. There are multiple knowledge gaps in selecting patients for adjuvant therapy. It is of great importance to establish risk calculators to predict recurrence and to implement molecular profiling of ACC to guide adjuvant therapy. The role of immunotherapy in metastatic ACC is emerging and if deemed efficacious, then future studies will be needed to ascertain the role of adjuvant immunotherapy in ACC.

The clinical utility of 'GRAS' parameters in stage I-III adrenocortical carcinomas: long-term data from a high-volume institution

BACKGROUND

Adrenocortical carcinoma (ACC) is a rare cancer with poor survival. We sought to identify prognostic factors and assess its clinical utility in postoperative management of nonmetastatic ACC.

METHODS

We included 65 patients who underwent adrenalectomy and clinicopathological diagnosed as European Network for the Study of Adrenal Tumors (ENSAT) stage I-III ACC in our center from 2009 to 2017. Potential clinicopathological parameters were selected. The prognostic correlation, including overall survival (OS) and recurrence-free survival (RFS), was analyzed using Kaplan-Meier method and univariate and multivariate Cox model.

RESULTS

The 2-year and 5-year post-surgery survival rate were 54.6% (95%CI: 42.5-70.1%) and 33.5% (95%CI: 22.3-50.6%), respectively. 46 (70.8%) cases were symptomatic ACC. Tumor-related or hormone-related symptom was identified as independent prognostic factor in OS (HR = 5.5, 95%CI: 1.87-16.16) and RFS (HR = 3.62, 95%CI: 1.28-10.24). Higher tumor grade (Weiss score > 6 or Ki67 index ≥ 20%) was independently associated with poor OS (HR = 4.73, 95%CI: 2.15-10.43). R status (R1/R2/Rx) was independently correlated with worse RFS (HR = 2.56, 95%CI:1.21-5.43). Accordingly, patients with higher GRAS (Grade, R status, age, and symptoms) score were more likely to have poor prognosis (OS: HR = 2.7, 95%CI: 1.43-5.11 and RFS: HR = 3.31, 95%CI: 1.68-6.52, respectively).

CONCLUSIONS

Symptoms, higher tumor grade and positive/unknown R status were independent risk factors in stage I-III ACC. Comprehensive consideration of GRAS parameters may optimize the prognostic assessment for postoperative patients.

Mitotane Concentrations Influence the Risk of Recurrence in Adrenocortical Carcinoma Patients on Adjuvant Treatment

Mitotane is used as a post-operative adjuvant treatment for patients with adrenocortical carcinoma. Monitoring of plasma mitotane concentrations is recommended, but we do not know what impact target concentrations have on patient outcome. To answer this question, we retrospectively analyzed patient records in the Lysosafe Online^® database (HRA Pharma, France) for patients who were treated for ≥6 months and who had ≥3 measurements of plasma mitotane levels during follow-ups at 11 tertiary centers in Italy from 2005 to 2017. We identified 110 patients treated with adjuvant mitotane for a median of 46 months (IQR, interquartile range, 28–62) with a median maintenance dose of 2.0 g/day (IQR 1.5–2.5). Achievement of target mitotane concentrations (≥14 mg/L) required a median of 8 months (IQR 5–19). Female sex was associated inversely with the dose, while body mass index (BMI) was correlated positively. Multivariate analysis showed that the Ki67 index and time to achieve the target range of plasma mitotane were independent predictors of recurrence-free survival (RFS). In a separate multivariate model, considering only the maintenance phase (month 7 to month 36, M7–M36) of treatment, the time in the target range of plasma mitotane was associated with a significantly lower risk of recurrence (Hazard Ratio, HR = 0.93; 0.88–0.98, p < 0.01). The prognostic implications of the time in target range and the time needed to reach target mitotane concentrations support the use of mitotane monitoring and may inform practice.