CT-guided versus MR-guided radiotherapy: Impact on gastrointestinal sparing in adrenal stereotactic body radiotherapy

BACKGROUND AND PURPOSE

To quantify the indication for adaptive, gated breath-hold (BH) MR-guided radiotherapy (MRgRT_BH) versus BH or free-breathing (FB) CT-based image-guided radiotherapy (CT-IGRT) for the ablative treatment of adrenal malignancies.

MATERIALS AND METHODS

Twenty adrenal patients underwent adaptive IMRT MRgRT_BH to a median dose of 50 Gy/5 fractions. Each patient was replanned for VMAT CT-IGRT_BH and CT-IGRT_FB on a c-arm linac. Only CT-IGRT_FB used an ITV, summed from GTVs of all phases of the 4DCT respiratory evaluation. All used the same 5 mm GTV/ITV to PTV expansion. Metrics evaluated included: target volume and coverage, conformality, mean ipsilateral kidney and 0.5 cc gastrointestinal organ-at-risk (OAR) doses (D_0.5cc). Adaptive dose for MRgRT_BH and predicted dose (i.e., initial plan re-calculated on anatomy of the day) was performed for CT-IGRT_BH and MRgRT_BH to assess frequency of OAR violations and coverage reductions for each fraction.

RESULTS

The more common VMAT CT-IGRT_FB, with its significantly larger target volumes, proved inferior to MRgRT_BH in mean PTV and ITV/GTV coverage, as well as small bowel D_0.5cc. Conversely, VMAT CT-IGRT_BH delivered a dosimetrically superior initial plan in terms of statistically significant (p ≤ 0.02) improvements in target coverage, conformality and D_0.5cc to the large bowel, duodenum and mean ipsilateral kidney compared to IMRT MRgRT_BH. However, non-adaptive CT-IGRT_BH had a 71.8% frequency of predicted indications for adaptation and was 2.8 times more likely to experience a coverage reduction in PTV D_95% than predicted for MRgRT_BH.

CONCLUSION

Breath-hold VMAT radiotherapy provides superior target coverage and conformality over MRgRT_BH, but the ability of MRgRT_BH to safely provide ablative doses to adrenal lesions near mobile luminal OAR through adaptation and direct, real-time motion tracking is unmatched.

Live birth after in-vitro maturation of oocytes in a patient with specific ovarian insufficiency caused by long-term mitotane treatment for adrenocortical carcinoma

RESEARCH QUESTION

How should the fertility of a woman with persistent specific ovarian dysfunction after long-term mitotane exposure be managed?

DESIGN

Case report. A 33-year-old woman who underwent surgery for adrenocortical carcinoma and treated with mitotane was referred for infertility. She rapidly became amenorrhoeic while taking mitotane, a condition that persisted for 5 years after cessation. Repeated serum hormone evaluation showed collapsed androgen levels, low oestradiol, high gonadotrophins (LH 69 and 63; FSH 23 and 43 IU/l), relatively high inhibin B level and slightly decreased anti-Müllerian hormone levels (1.4 and 0.7 ng/ml). An ultrasound scan revealed an antral follicle count of 13, contrasting with high serum gonadotrophin levels. After failure to obtain follicular growth after ovarian stimulation, in-vitro maturation (IVM) of immature oocytes aspirated from the antral follicles was carried out for microinjection with the spermatozoa of the patient's partner.

RESULTS

Two cycles of unstimulated egg retrieval were carried out, producing seven IVM oocytes, which were microinjected. A total of three cleavage-stage embryos were vitrified and unsuccessfully transferred after endometrial preparation using hormone replacement therapy (HRT). After a 20-month break, two new attempts were carried out under HRT with the aim of achieving a fresh embryo transfer. The last attempt succeeded after transfer of a single day-2 embryo, and the patient delivered a healthy baby.

CONCLUSION

Persistent specific impaired ovarian function 5 years after withdrawal of mitotane, and the first live birth after IVM in this situation, are reported. The question of fertility preservation before long-term mitotane treatment is raised.

A 25 year perspective on advances in the pathologic assessment and diagnosis of urologic cancers

Over the past 25 years, diagnostic categories in genitourinary pathology have changed dramatically. Prostate cancer reporting incorporated numerous new variant categories, recognized the importance of intraductal carcinoma, and introduced the concept of Grade Groups. Pathologic diagnosis of bladder cancer not only added new variant categories, but also modified the grading of non-invasive urothelial neoplasms and refined staging definitions. Kidney cancer classification expanded from a handful of diagnostic categories to a broad array of additional cancer types defined by unique immunohistochemical and molecular findings. Segregation of penile carcinoma by human papillomavirus status more accurately reflected pathogenesis and helped improve prediction of cancer behavior. Testicular pathology research advanced understanding of germ cell tumor subtypes and their impact on patient outcomes. Finally, adrenal gland pathology has evolved to incorporate a broader recognition of morphological variation and risk factors associated with tumor progression. Taken together, changes in pathology over the past quarter century have revolutionized our approach to genitourinary cancers. This review seeks to highlight some of the many significant changes in genitourinary pathology that have occurred during the past 25 years and emphasize impacts on clinical outcomes or therapy, as relevant.

β-catenin in adrenal zonation and disease

The Wnt signaling pathway is a critical mediator of the development and maintenance of several tissues. The adrenal cortex is highly dependent upon Wnt/β-catenin signaling for proper zonation and endocrine function. Adrenocortical cells emerge in the peripheral capsule and subcapsular cortex of the gland as progenitor cells that centripetally differentiate into steroid hormone-producing cells of three functionally distinct concentric zones that respond robustly to various endocrine stimuli. Wnt/β-catenin signaling mediates adrenocortical progenitor cell fate and tissue renewal to maintain the gland throughout life. Aberrant Wnt/β-catenin signaling contributes to various adrenal disorders of steroid production and growth that range from hypofunction and hypoplasia to hyperfunction, hyperplasia, benign adrenocortical adenomas, and malignant adrenocortical carcinomas. Great strides have been made in defining the molecular underpinnings of adrenocortical homeostasis and disease, including the interplay between the capsule and cortex, critical components involved in maintaining the adrenocortical Wnt/β-catenin signaling gradient, and new targets in adrenal cancer. This review seeks to examine these and other recent advancements in understanding adrenocortical Wnt/β-catenin signaling and how this knowledge can inform therapeutic options for adrenal disease.

Prolonged Adrenal Insufficiency After the Discontinuation of Mitotane Therapy

INTRODUCTION

Adrenocortical carcinoma (ACC) is a rare neoplasm characterized by a high risk of recurrence after radical resection. The role of adjuvant systemic therapy in radically resected patients is unclear. Mitotane, a steroidogenesis inhibitor, is the only drug approved for the systemic treatment of advanced ACC. In 2007, a retrospective case-control study provided the evidence that mitotane, administered for two years after successful surgery, could prolong recurrence-free survival. Adrenal insufficiency (AI), which occurs in almost all patients during the first 12 months of treatment, is an expected side effect of mitotane and requires steroid replacement therapy. Due to its long halflife, mitotane-induced AI persists several months after treatment discontinuation and is managed by cautious tapering of glucocorticoid replacement therapy.

RESULTS

We report a case of symptomatic AI diagnosed after a severe allergic reaction occurring three years after the discontinuation of adjuvant mitotane therapy.

CONCLUSION

The case suggests that mitotane-induced AI should be monitored for a long time to asses full recovery of adrenal function, in order to prevent adrenal crises.

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.

An update on adrenal endocrinology: significant discoveries in the last 10 years and where the field is heading in the next decade

The last 10 years have produced an amazing number of significant discoveries in the field of adrenal endocrinology. The development of the adrenal gland was linked to specific molecules. Cortisol-producing lesions were associated mostly with defects of the cyclic AMP (cAMP) signaling pathway, whereas aldosterone-producing lesions were found to be the result of defects in aldosterone biosynthesis or the potassium channel KCNJ5 and related molecules. Macronodular adrenal hyperplasia was linked to ARMC5 defects and new genes were found to be involved in adrenocortical cancer (ACC). The succinate dehydrogenase (SDH) enzyme was proven to be the most important molecular pathway involved in pheochromocytomas, along with several other genes. Adrenomedullary tumors are now largely molecularly elucidated. Unfortunately, most of these important discoveries have yet to produce new therapeutic tools for our patients with adrenal diseases: ACC in its advanced stages remains largely an untreatable disorder and malignant pheochromocytomas are equally hard to treat. Thus, the challenge for the next 10 years is to translate the important discoveries of the previous decade into substantial advances in the treatment of adrenal disorders and tumors.

Cushing's Syndrome in Pediatrics: An Update

Cushing syndrome (CS) is a multisystem disorder resulting from the prolonged exposure to excess glucocorticoids. In children, CS most commonly results from the exogenous administration of steroids and the typical presentation is height deceleration concomitant with weight gain. Endogenous and ectopic causes are rare. CS in children may be associated with distinct germline and somatic mutations. Clinical practice guidelines are available assist clinicians. Patients should be referred to multidisciplinary centers of excellence with experience in endocrinology and surgery. Early detection and treatment is essential to reduce associated acute and long-term morbidity and potential death.

Adrenocortical carcinoma: the dawn of a new era of genomic and molecular biology analysis

Over the last decade, the development of novel and high penetrance genomic approaches to analyze biological samples has provided very new insights in the comprehension of the molecular biology and genetics of tumors. The use of these techniques, consisting of exome sequencing, transcriptome, miRNome, chromosome alteration, genome, and epigenome analysis, has also been successfully applied to adrenocortical carcinoma (ACC). In fact, the analysis of large cohorts of patients allowed the stratification of ACC with different patterns of molecular alterations, associated with different outcomes, thus providing a novel molecular classification of the malignancy to be associated with the classical pathological analysis. Improving our knowledge about ACC molecular features will result not only in a better diagnostic and prognostic accuracy, but also in the identification of more specific therapeutic targets for the development of more effective pharmacological anti-cancer approaches. In particular, the specific molecular alteration profiles identified in ACC may represent targetable events by the use of already developed or newly designed drugs enabling a better and more efficacious management of the ACC patient in the context of new frontiers of personalized precision medicine.

Management of Adrenal Masses

An adrenal mass can be either symptomatic or asymptomatic in the form of adrenal incidentalomas (AIs) in up to 8 % in autopsy and 4 % in imaging series. Once a diagnosis of adrenal mass is made, we need to differentiate whether it is functioning or nonfunctioning, benign, or malignant. In this article, we provide a literature review of the diagnostic workup including biochemical evaluation and imaging characteristics of the different pathologies. We also discuss the surgical strategies with laparoscopy as the mainstay with partial adrenalectomy in select cases and adrenalectomy in large masses. Follow-up protocol of AIs and adrenocortical carcinoma is also discussed.

The ER-mitochondria couple: In life and death from steroidogenesis to tumorigenesis

Steroidogenesis is a multistep process where interorganelle communications between the endoplasmic reticulum and mitochondria are critical. These intimate interactions physically occur through the Mitochondria-Associated ER membranes called MAMs. MAMs play important roles in mitochondrial morphology and in many cellular functions ranging from lipid metabolism, to calcium signaling and apoptosis together with a critical effect on steroidogenesis. Moreover, our recent characterization of new MAM resident proteins in adrenocortical cells extends the function of MAM in the mechanism of resistance of cancer cells to apoptotic stimuli and offers new perspectives in targeted therapeutic approaches for adrenocortical tumorigenesis.

Angiosarcoma of the Adrenal Gland Treated Using a Multimodal Approach

Angiosarcoma of the adrenal gland is an extremely rare malignancy. We report a case of a 59-year-old female who presented with abdominal pain and profound anemia. A 7 cm enhancing, lipid-poor adrenal mass with calcifications that extended posterior to the vena cava was identified on imaging. Patient underwent right adrenalectomy with retroperitoneal lymph node dissection. Pathology demonstrated angiosarcoma of the adrenal gland. Consolidative treatment included adjuvant radiation and chemotherapy. Patient remains disease free 1.5 years following treatment. Prior reported literature on the diagnosis and management of adrenal angiosarcoma is reviewed.

Biology is Destiny: A Case of Adrenocortical Carcinoma Diagnosed and Resected at Inception in a Patient Under Close Surveillance for Lung Cancer

Adrenocortical carcinoma (ACC) is a rare malignancy that is generally associated with a poor prognosis whose existence dictates the management of incidental renal masses. We report a case of ACC diagnosed and treated at its apparent inception in a patient undergoing close surveillance imaging of a prior malignancy. Despite timely detection and resection of a localized ACC this patient rapidly progressed to systemic disease. This case highlights the rapid growth kinetics of ACC and puts into perspective the challenges associated with the established treatment paradigm for patients diagnosed with an adrenal mass.

Drug Synergism of Proteasome Inhibitors and Mitotane by Complementary Activation of ER Stress in Adrenocortical Carcinoma Cells

Mitotane is the only drug approved for treatment of the orphan disease adrenocortical carcinoma (ACC) and was recently shown to be the first clinically used drug acting through endoplasmic reticulum (ER)-stress induced by toxic lipids. Since mitotane has limited clinical activity as monotherapy, we here study the potential of activating ER-stress through alternative pathways. The single reliable NCI-H295 cell culture model for ACC was used to study the impact MG132, bortezomib (BTZ) and carfilzomib (CFZ) on mRNA and protein expression of ER-stress markers, cell viability and steroid hormone secretion. We found all proteasome inhibitors alone to trigger expression of mRNA (spliced X-box protein 1, XBP1) and protein markers indicative of the inositol-requiring enzyme 1 (IRE1) dependent pathway of ER-stress but not phosphorylation of eukaryotic initiation factor 2α (eIF2α), a marker of the PRKR-like endoplasmic reticulum kinase (PERK)-dependent pathway. Whereas mitotane alone activated both pathways, combination of BTZ and CFZ with low-dose mitotane blocked mitotane-induced eIF2α phosphorylation but increased XBP1-mRNA splicing indicating that proteasome inhibitors can commit signalling towards a single ER-stress pathway in ACC cells. By applying the median effect model of drug combinations using cell viability as a read out, we determined significant drug synergism between mitotane and both BTZ and CFZ. In conclusion, combination of mitotane with activators of ER-stress through the unfolded protein response is synergistic in an ACC cell culture model. Since proteasome inhibitors are readily available clinically, they are attractive candidates to study for ACC treatment in clinical trials in combination with mitotane.

Adrenal oncoctyoma of uncertain malignant potential: a rare etiology of adrenal incidentaloma

A rare cause for rapid adrenal enlargement is adrenal oncocytoma of uncertain malignant potential. A full biochemical evaluation is warranted to screen secreting adrenal adenomas as well as to evaluate adrenal cortical carcinoma. Careful pathologic evaluation is required as the diagnosis of AOC cannot be made by imaging.

Applicability of laparoscopic approach to the resection of large adrenal tumours: a retrospective cohort study on 200 patients

BACKGROUND

Controversies exist in the best surgical approach (open vs. laparoscopy) to large adrenal tumours without peri-operative evidence of primary carcinoma, mainly due to possible capsular disruption of an unsuspected malignancy. In addition, intra-operative blood loss, conversion rate, operative time, and hospital stay may be increased with laparoscopy.

THE AIMS OF OUR STUDY WERE

(1) to compare clinical outcomes of laparoscopic adrenalectomy for large versus small adrenal tumours and (2) to identify risk factors associated with increased operative time and hospital stay in laparoscopic adrenalectomy.

METHODS

This is a multicentre retrospective cohort study in a large patient population (N = 200) who underwent laparoscopic adrenalectomy in 2004-2014 at three Italian academic hospitals. Patients were divided into two cohorts according to tumour size: "large" tumours were defined as ≥5 cm (N = 50) and "small" tumours as <5 cm (N = 150). Further analysis adopting a ≥8 cm (N = 15) cut-off size was performed.

RESULTS

The study groups were comparable in age and gender distribution as well as their tumour characteristics. The operative time (p = 0.671), conversion rate (p = 0.488), intra- (p = 0.876) and post-operative (p = 0.639) complications, and hospital stay (p = 0.229) were similar between groups. With a cut-off size ≥5 cm, the early study period (2004-2009), which included operators' learning curve, was associated with increased risk of longer operative time (HR 0.57; 95 % CI 0.40-0.82), while American Society of Anaesthesiology score ≥3 was associated with prolonged hospital stay (HR 0.67; 95 % CI 0.47-0.97). Tumour size ≥8 cm was associated with prolonged operative time (HR 0.47; 95 % CI 0.24-0.94).

CONCLUSIONS

Surgeons skilled in advanced laparoscopy and adrenal surgery can perform laparoscopic adrenalectomy safely in patients with ≥5-cm tumours with no increase in hospital stay, or conversion rate, although operative time may be increased for ≥8-cm tumours. Surgeon' experience, size ≥8 cm, and patient comorbidities have the largest impact on operative time and length of hospital stay in laparoscopic large adrenal tumour resection.

Adrenocortical carcinoma: what the surgeon needs to know. Case report and literature review

Adrenocortical carcinoma is a rare and aggressive cancer and its prognosis is frequently unsatisfactory. Due to its rarity there's a lack of prospective randomized studies. Without experience in the approach of this kind of tumor, managing becomes challenging and, moreover, we have only few recommendations, based on weak evidence. We report a case that has some peculiarities and is an excellent food for thought. Then we deal with a literature review to highlight and summarize most significant aspects of epidemiology, clinic, diagnosis, therapy and prognosis in an exquisitely surgical point of view.

Imaging of adrenal incidentaloma: our experience

PURPOSE

To investigate clinical, biochemical and radiological features in 35 patients with adrenal incidentaloma found on CT and/or MRI and to define the management of patients with adrenal masses.

MATHERIAL AND METHODS

From January 2011 and May 2013, 35 patients (19F, 16M) with an adrenal mass incidentally discovered on CT and/or MRI were enrolled in a retrospective study. Thirthy-two patients underwent MDCT and eight 1.5 MRI.

RESULTS

Patients consisted in 16 males and 19 females, aged between 25 and 89 yo. Adrenal lesions were most commonly found in the sixth decade; in relation to the side of the mass, 20 were found on left side, 15 on the right. Of all the mass analyzed, 3 were <1 cm diameter, 29 between 1 and 4 cm, 3 > 4 cm. The most common finding on CT was adenoma-like appearance (19 cases in relation to size, 14 in relation to attenuation values). Hormonal analysis showed 32 cases of nonfunctional masses and 3 cases of hormone activity. Adrenalectomy was performed in ten patients having adenoma (5 cases), malignant lesions (2 cases), pheocromocitoma, cyst and myelolipoma (1 case).

CONCLUSION

Diagnostic approach to adrenal incidentaloma is focused on the definition of malignancy and hormonal activity; the characterization is needs hormonal and radiological (CT and/or MRI) evaluation, even if a fine needle aspiration is needed in selected cases. Benign and/or non-hypersecreting hormone lesion with <4 cm diameter could be sent to follow-up; active adrenal tumors or >4 cm diameter lesions with malignancy suspicious or growth during follow-up could be treated with surgical adrenalectomy.

Normal delivery following resection of an androgen-secreting adrenal carcinoma

A 31-year-old female presented to a gynecological clinic complaining of amenorrhea and virilism over a 2-month period. Blood tests revealed high serum total testosterone and free testosterone levels. A left adrenal tumor was identified following computed tomography and she was referred to our clinic where a laparoscopic left adrenalectomy was performed. The tumor weighed 98 g and the pathological diagnosis according to Weiss' criteria was adrenocortical carcinoma. The post-operative course was uneventful; her serum free testosterone level normalized and regular menstruation was observed 1 month post-operatively. The patient became pregnant 1 year later, resulting in the normal delivery of a girl.