Practical Considerations in the Evaluation and Management of Adrenocortical Cancer

Activity of the Ubiquitin-activating Enzyme Inhibitor TAK-243 in Adrenocortical Carcinoma Cell Lines, Patient-derived Organoids, and Murine Xenografts

Current treatment options for metastatic adrenocortical carcinoma (ACC) have limited efficacy, despite the common use of mitotane and cytotoxic agents. This study aimed to identify novel therapeutic options for ACC. An extensive drug screen was conducted to identify compounds with potential activity against ACC cell lines. We further investigated the mechanism of action of the identified compound, TAK-243, its synergistic effects with current ACC therapeutics, and its efficacy in ACC models including patient-derived organoids and mouse xenografts. TAK-243, a clinical ubiquitin-activating enzyme (UAE) inhibitor, showed potent activity in ACC cell lines. TAK-243 inhibited protein ubiquitination in ACC cells, leading to the accumulation of free ubiquitin, activation of the unfolded protein response, and induction of apoptosis. TAK-243 was found to be effluxed out of cells by MDR1, a drug efflux pump, and did not require Schlafen 11 (SLFN11) expression for its activity. Combination of TAK-243 with current ACC therapies (e.g., mitotane, etoposide, cisplatin) produced synergistic or additive effects. In addition, TAK-243 was highly synergistic with BCL2 inhibitors (Navitoclax and Venetoclax) in preclinical ACC models including patient-derived organoids. The tumor suppressive effects of TAK-243 and its synergistic effects with Venetoclax were further confirmed in a mouse xenograft model. These findings provide preclinical evidence to support the initiation of a clinical trial of TAK-243 in patients with advanced-stage ACC. TAK-243 is a promising potential treatment option for ACC, either as monotherapy or in combination with existing therapies or BCL2 inhibitors.

SIGNIFICANCE

ACC is a rare endocrine cancer with poor prognosis and limited therapeutic options. We report that TAK-243 is active alone and in combination with currently used therapies and with BCL2 and mTOR inhibitors in ACC preclinical models. Our results suggest implementation of TAK-243 in clinical trials for patients with advanced and metastatic ACC.

Metastatic and recurrent adrenocortical cancer is not defined by its genomic landscape

Background

Adrenocortical carcinoma (ACC) is a rare, often-aggressive neoplasm of the adrenal cortex, with a 14–17 month median overall survival. We asked whether tumors from patients with advanced or metastatic ACC would offer clues as to putative genes that might have critical roles in disease progression or in more aggressive disease biology.

Methods

We conducted comprehensive genomic and expression analyses of ACCs from 43 patients, 30 female, and 42 from metastatic sites, including deep sequencing, copy number analysis, mRNA expression and microRNA arrays.

Results

Copy number gains and losses were similar to that previously reported for ACC. We identified a median mutation rate of 3.38 per megabase (Mb). The mutational signature was characterized by a predominance of C > T, C > A and T > C transitions. Only cancer genes TP53 (26%) and beta-catenin (CTNNB1, 14%) were mutated in more than 10% of samples. The TCGA-identified putative cancer genes MEN1 and PRKAR1A were found in low frequency—4.7 and 2.3%, respectively. The majority of the mutations were in genes not implicated in the etiology or maintenance of cancer. Specifically, amongst the 38 genes that were mutated in more than 9% of samples, only four were represented in Tier 1 of the 576 COSMIC Cancer Gene Census (CCGC). Thus, 82% of genes found to have mutations likely have no role in the etiology or biology of ACC; while the role of the other 18%, if any, remains to be proven. Finally, the transcript length for the 38 most frequently mutated genes in ACC is statistically longer than the average of all coding genes, raising the question of whether transcript length in part determined mutation probability.

Conclusions

We conclude that the mutational and expression profiles of advanced and metastatic tumors are very similar to those from newly diagnosed patients—with very little in the way of genomic aberration to explain differences in biology. With relatively low mutation rates, few major oncogenic drivers, and loss of function mutations in several epigenetic regulators, an epigenetic basis for ACC may be postulated and serve as the basis for future studies.

A rare case of oncocytic adrenocortical carcinoma clinically presented as an incidentaloma

Adrenocortical carcinoma (ACC) is a rare aggressive tumor originating from adrenocortical parenchymal cells and its incidence is approximately 1 per million population per year. An oncocytic ACC is a recently identified entity among the several known histopathological variants of ACC, which is characterized by oncocytic cells, and only a few cases in the available literature have reported this tumor. In contrast to conventional ACCs, oncocytic ACCs usually manifest as solitary lesions presenting in adults without any sex predilection. We report a case of a 70-year-old Japanese man who presented with an incidentally discovered retroperitoneal mass without any evidence of excessive corticosteroid secretion. Laboratory and imaging studies, as well as transgastric endoscopic ultrasound-guided fine needle aspiration failed to establish a definitive diagnosis. Thus, the patient underwent surgical resection of the left-sided peritoneal tumor. Weiss score was positive in 6/9 points and the tumor met two major criteria of the Lin-Weiss-Bisceglia (LWB) system leading to a diagnosis of an oncocytic variant of ACC. Based on our findings in this patient, we conclude that a combination of the Weiss and LWB criteria is required to determine the malignant potential of oncocytic adrenal tumors because ACCs and oncocytomas could be frequently indistinguishable. Careful histopathological examination is pivotal in confirming the oncocytic component in the lesion and hence definitive diagnosis of ACCs.

A novel case of myxoid variant of adrenocortical carcinoma in a patient with multiple endocrine neoplasia type 1

Adrenocortical carcinoma (ACC) is a rare malignancy arising from adrenocortical parenchymal cells. Myxoid ACC is one of the newly identified, rare, but important histological variants of ACC, characterized by the presence of abundant extracellular Alcian Blue-positive myxoid material. Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant cancer predisposition syndrome, and the incidence of ACC in MEN1 patients has been reported to be between 1.4% and 6%. Here, we report the case of a 68-year-old Japanese woman harboring the past history of MEN1 associated with insulinoma, pituitary tumor, and hyperparathyroidism. She presented to our hospital with hypertension and hypokalemia. Imaging studies revealed a right adrenal tumor, and histological examination revealed myxoid ACC. Despite surgical resection of the tumor and mitotane therapy, the patient died 6 months after the surgery. To the best of our knowledge, this is the first reported case of the myxoid variant of ACC in a patient with MEN1. The patient's clinical course was characterized by the development of both multiple endocrine and non-endocrine neoplasm, hyperaldosteronism, and aggressive biological behavior. This case confirmed that myxoid morphology was also associated with aggressive behavior in ACC, but further studies are required to clarify the association between MEN1 and myxoid ACC.

A rare case of ectopic ACTH syndrome originating from malignant renal paraganglioma

Ectopic adrenocorticotropic hormone (ACTH) syndrome is characterized by hypercortisolism due to the hypersecretion of a non-pituitary ACTH-secreting tumor leading to Cushing's syndrome. Only a few cases have been reported previously as causing ectopic ACTH related to paraganglioma. Herein, we present a case of Cushing's syndrome, in who was proved to be attributable to an ACTH-secreting renal malignant paraganglioma. A 40-year-old woman presented with a five-month history of newly diagnosed hypertension and diabetes, weakness, hyperpigmentation, oligomenorrhea, hirsutism, and acneiform lesions. She showed cushingoid features, including moon face, facial hirsutism, facial and truncal acne, hyperpigmentation, and severe muscle weakness of the limbs. She did not have other findings such as striae, supraclavicular fat accumulation, and buffalo hump. Laboratory examination showed the presence of hypopotasemia, hyperglycemia, hyperthyroidism, and leukocytosis. The serum levels of ACTH, cortisol, and urine-free cortisol were markedly elevated. Results of an overnight 2-mg dexamethasone suppression test included a basal serum cortisol of 61.1 mcg/dL (normal range: 4.6-22.8 mcg/dL) and a cortisol value of 46.1 mcg/dL after dexamethasone administration. There was no suppression found after 2-day 8-mg dexamethasone administration. Magnetic resonance imaging (MRI) of the pituitary gland indicated two microadenomas. An abdominal MRI scan revealed horseshoe kidney, bilateral adrenal hyperplasia, and masses with dimensions of 35 x 31 mm in the left kidney. Inferior petrosal sinus sampling showed no evidence of a central-to-peripheral gradient of ACTH. A positron emission tomography/computed tomography scan showed intense increased activity in the lower pole of the left kidney. Left adrenalectomy and left partial nephrectomy were performed. The resected tumor was diagnosed as the ACTH-secreting paraganglioma in the pathological examination, which was confirmed by immunohistochemical studies with chromogranin A, synaptophysin, and ACTH. Only a few cases of paragangliomas as a cause of ectopic ACTH syndrome have been reported. To our knowledge, this is the first case of renal paraganglioma resulting in Cushing's syndrome due to ectopic ACTH hypersecretion.

Proteome analysis of adrenal cortical tumors

INTRODUCTION

Adrenal tumor is a relatively common tumor. The discrimination between adrenal cortical adenoma (ACA) and adrenal cortical carcinoma (ACC) is crucial as these two diseases have distinct prognosis. ACA is a benign tumor curable by surgical excision, while the prognosis of ACC is extremely poor, with a 5-year mortality of 75-90%. Therefore, previous proteomic studies focused on markers allowing the differentiation between ACA and ACC.

AREAS COVERED

Several proteomic approaches based on the analysis of various samples such as human tissues, urine, and cell lines. In this review, we focused on proteomic studies performed to improve adrenal tumor diagnosis and identify ACC therapeutic targets. Expert commentary: The rapid development of cancer genomics provided a lot of information, which affects functional proteomics. In practice, differentially expressed proteins between ACA and ACC have been suggested in several proteomic studies and had a biologic implication in ACC.

Adrenocortical carcinoma: modern management and evolving treatment strategies

Adrenocortical carcinoma (ACC) is a rare cancer with a poor prognosis. Unlike many other cancers, there has been little improvement in patient outcome over the past several decades. However, as scientific advancements are made and our understanding of the molecular genetics involved in ACC improve then progress may be achieved in this devastating disease. This review focuses on recent literature published in the field of ACC from 2010 to 2015 with an emphasis on improving diagnosis, staging and treatment for ACC.

Adrenocortical carcinoma: review of the pathologic features, production of adrenal steroids, and molecular pathogenesis

Adrenocortical carcinoma (ACC) is a malignant neoplasm often associated with an aggressive biological behavior. The histologic differentiation between ACC and adrenocortical adenoma (ACA) is largely determined by employing the Weiss criteria, although this classification may not apply to all the cases. Additionally, various genomic features of ACC could be an auxiliary mode to establish the diagnosis of ACC. Most ACC cases are hormonally functional, and immunohistochemical analysis of steroidogenic enzymes has provided pivotal information as to the analysis of intratumoral production of corticosteroids. This article summarizes the current status of the histopathological diagnosis, molecular pathogenesis, and hormonal features of ACC.

Aldosterone-secreting adrenal cortical carcinoma. A case report and review of the literature

Adrenal cortical carcinomas (ACC) are rare, typically aggressive malignant neoplasms with a reported incidence of 1-2 cases per 1 million population and account for 0.05-0.2 % of all malignancies. The majority of these tumors are functional with approximately 60 % of patients experiencing endocrine symptomatology typically characterized by Cushing's syndrome (40 %) or a mixed hormonal picture of Cushing syndrome seen in association with virilization. Rarely, patients present with a pure hormonal syndrome of feminization or hyperaldosteronism, 6 and 2.5 %, respectively. We report a case of a 76-year-old woman presenting with recently diagnosed hypertension secondary to primary hyperaldosteronism. The patient underwent laparoscopic converted to an open adrenalectomy and a diagnosis of adrenocortical carcinoma (aldosteronoma clinical) was rendered. This case and review of the literature highlight that while rare, aldosterone-secreting adrenal cortical carcinomas may occur. In this case report, we discuss the clinical presentation, pathologic findings, and review the literature for adrenal cortical carcinomas and aldosterone-secreting adrenal cortical carcinomas.

Long-term survival after adrenalectomy for stage I/II adrenocortical carcinoma (ACC): a retrospective comparative cohort study of laparoscopic versus open approach

BACKGROUND

Laparoscopic adrenalectomy (LA) is the standard treatment for benign adrenal lesions. The laparoscopic approach has also been increasingly accepted for adrenal metastases but remains controversial for adrenocortical carcinoma (ACC). In a retrospective cohort study we compared the outcome of LA versus open adrenalectomy (OA) in the treatment of stage I and II ACC.

METHODS

This was a double cohort study comparing the outcome of patients with stage I/II ACC and a tumor size <10 cm submitted to LA or OA at Lille University Hospital referral center from 1985 to 2011. Main outcomes analyzed were: postoperative morbidity, overall survival, and disease-free survival.

RESULTS

Among 111 consecutive patients operated on for ACC, 34 met the inclusion criteria. LA and OA were performed in 13 and 21 patients, respectively. Baseline patient characteristics (gender, age, tumor size, hormonal secretion) were similar between groups. There was no difference in postoperative morbidity, but patients in LA group were discharged earlier (p < 0.02). After a similar follow-up (66 ± 52 for LA and 51 ± 43 months for OA), Kaplan-Meier estimates of disease-specific survival and disease-free survival were identical in both groups (p = 0.65, p = 0.96, respectively).

CONCLUSIONS

LA was associated with a shorter length of stay and did not compromise the long-term oncological outcome of patients operated on for stage I/II ACC ≤ 10 cm ACC. Our results suggest that LA can be safely proposed to patients with potentially malignant adrenal lesions smaller than 10 cm and without evidence of extra-adrenal extension.

Role of radiotherapy in adrenocortical carcinoma

PURPOSE

Adrenocortical carcinoma (ACC) is a rare and highly malignant tumor usually diagnosed in an advanced stage. Radiation therapy has been a poorly studied and underutilized therapeutic option.

METHODS

This retrospective analysis reviewed treatment courses for 14 patients with pathologically confirmed ACC treated between 1997 and 2012. Two patients were treated adjuvantly following surgery, and 12 were treated with palliative intent. Patients presented with stage II (n = 4), stage III (n = 7), and stage IV (n = 3) disease. Patients had a mean age of 51.5 years. Ten patients received chemotherapy before radiotherapy (RT), and 12 patients received surgery before RT, before receiving radiation at a mean of 17.8 months after diagnosis.

RESULTS

In total, 20 sites were treated, 2 of which were in an adjuvant setting, and 18 of which were for palliative indications in 12 patients as follows: (1) pain/neuropathy (n = 10), (2) prophylactic treatment of asymptomatic recurrences (n = 3), and (3) prevention of imminent metastatic complications (n = 2), hemoptysis (n = 1), severe mass effect (n = 1), and brain metastasis (n = 1). Sites were treated to a median dose of 36.3 Gy (range, 17.5-60 Gy) in a median of 2.5 Gy/fraction (range, 1.8-4 Gy). At a mean follow-up of 22.0 months for the 2 patients given adjuvant RT, 1 patient did not have a local recurrence during a 14.3-month period of follow-up, and the other had a local recurrence 14.5 months after RT. At a mean follow-up of 11.3 months for the 12 patients receiving palliative RT, 10 patients had either a clinical or radiographic response. Of the courses of palliative RT that had adequate radiographic follow-up, 4 treatments (27%) resulted in a partial response. Eleven treatments (73%) that were able to be evaluated resulted in clinical improvement. Acute Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer toxicities observed in 7 patients included 3 grade 1, 4 grade 2, and 1 grade 3. No patient had acute toxicity of grade 4 or greater or any Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer late toxicity of grade 1 or greater.

DISCUSSION

This report is one of the largest to date examining the role of modern radiation techniques in the management of ACC. We conclude that radiation can be effective in the management of metastatic ACC, palliating local symptoms, and preventing complications from large metastases. Radiation should be considered as an option in multimodality management of ACC patients.

The next generation of therapies for adrenocortical cancers

Adrenocortical carcinoma (ACC) is a rare cancer for which few treatment options have been available. Currently, the best available treatment involves combination chemotherapy with the adrenolytic drug mitotane, although the response rate remains modest. Over the past 10 years there has been renewed interest in the field owing to the recognition that targeted therapies may provide new avenues for effective treatment of this deadly disease. Molecular analyses have revealed specific signaling alterations in ACC, and advances in drug development have generated the tools to block these pathways. Although convincing evidence for the effectiveness of targeted therapies is not currently available, these studies are in progress and should shift the prognosis of this disease in the years to come.

Molecular imaging of adrenal neoplasms

The adrenal glands are complex structures from which a variety of benign and malignant tumors may arise and are a common site of metastatic disease. Several radiopharmaceuticals are used for imaging the adrenals, including I-123/I-131 metaiodobenzylguanidine (MIBG), norcholesterol derivatives, In-111 pentetreotide and Ga-68 somatostatin analogs, [F-18]fluorodeoxyglucose, [F-18]fluorodopa, [F-18]fluorodopamine, C-11 meta hydroxyephedrine, and C-11/F-18/I-123 Metomidate (MTO) or its analogs. In this review we focus on the role of these reagents in metastatic lesions, cortical neoplasms, pheochromocytoma/paraganglioma, and neuroblastoma (NB).

Ribonucleotide reductase large subunit (RRM1) gene expression may predict efficacy of adjuvant mitotane in adrenocortical cancer

PURPOSE

Mitotane is the most broadly used systemic therapy for adrenocortical carcinoma (ACC), but its mechanism of action and possible predictors of treatment response are currently poorly defined. Our aim was to evaluate the gene expression of ribonucleotide reductase large subunit 1 (RRM1) and excision repair cross-complementation group 1 (ERCC1) in ACC as potential biomarkers for clinical outcome and response to mitotane.

EXPERIMENTAL DESIGN

Forty-five and 47 tissue samples from two cohorts (Orbassano, Italy; Wuerzburg, Germany) of completely resected ACC were centrally analyzed using real-time PCR for RRM1 and ERCC1 expression. Fifty-four patients received surgery alone and 38 received adjuvant mitotane after surgery. Clinical and pathologic features were highly comparable in the two series. H295R and SW-13 ACC cell lines were also used for pharmacologic tests.

RESULTS

ERCC1 gene expression was not associated to clinical outcome. In contrast, high RRM1 gene expression was associated to shorter disease-free survival (DFS) and overall survival at both univariate and multivariate analysis. In patients with low RRM1 gene expression, adjuvant mitotane was associated with improved DFS, whereas this effect was lost in cases with high RMM1 expression. In vitro mitotane induced strong up regulation of RRM1 transcription (up to 25-fold increase) in mitotane-insensitive SW-13 but not in mitotane-sensitive H295R cells. Furthermore, RRM1 silencing in SW-13 cells induced sensitivity to mitotane.

CONCLUSION

Our in vitro and in vivo data indicate that RRM1 gene expression is functionally associated to mitotane sensitivity and support a possible role of RRM1 determination as a novel molecular biomarker predicting response to adjuvant mitotane in ACC.

Adrenocortical carcinoma: past, present, and future

Adrenocortical carcinoma (ACC) is a rare endocrine malignancy. Due to its rarity, heterogeneity, and a lack of a comprehensive understanding of the pathogenesis, little progress has been made in treatment and outcomes. The current review explores the past, present, and future of the understanding and treatment of this disease process.

Hydrophilic coating of mitotane-loaded lipid nanoparticles: preliminary studies for mucosal adhesion

The aim of the present work was to load mitotane, an effective drug for adrenocortical carcinoma treatment, in solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC). The SLN and NLC were successfully prepared by high shear homogenization followed by hot high pressure homogenization. Formulations were composed of cetyl palmitate as the solid lipid for SLN, whereas for NLC PEGylated stearic acid was selected as solid lipid and medium chain triacylglycerols as the liquid lipid. Tween® 80 and Span® 85 were used as surfactants for all formulations. The particle size, zeta potential, polydispersity index (PI), encapsulation efficiency (EE), and loading capacity (LC) were evaluated. The SLN showed a mean particle size of 150 nm, PI of 0.20, and surface charge -10 mV, and the EE and LC could reach up to 92.26% and 0.92%, respectively. The NLC were obtained with a mean particle size of 250 nm, PI of 0.30, zeta potential -15 mV and 84.50% EE, and 0.84% LC, respectively. Hydrophilic coating of SLN with chitosan or benzalkonium chloride was effective in changing zeta potential from negative to positive values. The results suggest that mitotane was efficiently loaded in SLN and in NLC, being potential delivery systems for improving mitotane LC and controlled drug release.

Adrenocortical carcinoma: which surgical approach?

INTRODUCTION

There are no randomised studies comparing open and laparoscopic approaches foradrenalectomy in patients with adrenal cortical carcinoma.

METHODS

There is evidence of postoperative benefit for the patients undergoing laparoscopic adrenalectomy compared to open adrenalectomy (level B).

RESULTS

Results from comparison of oncological outcomes in ACC between open and laparoscopic approaches are equivocal: increasedrisk of local recurrence and peritoneal carcinomatosis by the laparoscopic route (level D), and identical results between the two approaches in terms of survival, recurrence and peritoneal carcinomatosis (level C).

CONCLUSION

An open approach is recommended in case of local invasion, with a view to achieving an R0 resection (level D). Laparoscopic resection of ACC/potentially malignant tumours, which includes removal of surrounding periadrenal fat and results in an R0 resection without tumour capsule rupture, may be performed for preoperative and intraoperative stage 1-2 ACC and tumours with a diameter < 10 cm (level C).

[Bilateral conjunctival oedema as a symptom of adrenal adenocarcinoma]

CLINICAL CASE

We present a case of a 67-year-old female suffering for bilateral conjunctival oedema that did not improve with antibiotic and antiinflammatory treatment. After a complete systemic examination she was diagnosed with an adrenal adenocarcinoma and treated by surgery and chemotherapy. The conjunctival chemosis subsequently improved. Unfortunately the patient died of respiratory failure due to metastasis.

CONCLUSION

We emphasise the need of an exhaustive and complete examination by the ophthalmologist in cases of non-responders to topical antibiotic and antiinflammatory treatment in patients with bilateral conjunctival oedema, in order to make a correct diagnosis of systemic potentially lethal diseases.