Mortality rate of adrenocortical tumors in children under 15 years of age in Curitiba, Brazil

Pubertal, Auxological, and Adult Height Outcomes in Children Treated for Adrenocortical Tumors: Half a Century Experience

INTRODUCTION

Most children with adrenocortical tumors (ACTs) present with accelerated growth and skeletal maturation at diagnosis, which potentially compromises their adult heights (AHs). Knowledge about growth and pubertal patterns after ACT resection is scarce. This study presents the pubertal and auxological development of patients treated for ACT and followed up at a single pediatric endocrinology service in Brazil.

METHODS

Retrospective cohort study including 63 patients (47 girls) followed up between 1966 and 2021. Pubertal and auxological data from ACT diagnosis to AH were analyzed.

RESULTS

At diagnosis, the patients had median values of bone age (BA) more advanced than chronological age (CA), height standard deviation score greater than target height (TH-SDS), and predicted adult height (PAH-SDS) lower than TH-SDS. The difference between BA and CA decreased gradually during follow-up and the PAH-SDS moved closer to the TH-SDS 7 years after tumor resection. Puberty started at a median CA of 9.3 (8.3-11.3) years in girls and 9.9 (9.2-13.6) years in boys. Nine patients (6 girls) developed central precocious puberty (CPP), which was influenced by a CA >4 years at diagnosis. The difference between AH-SDS and TH-SDS was not significant (p = 0.3). The factors independently associated with AH below TH were CA >4 years at diagnosis, time between clinical manifestation and diagnosis >1 year, and development of CPP.

CONCLUSION

Most patients treated for ACT during childhood attained AH within the TH despite presenting with advanced skeletal maturation at diagnosis. Development of CPP was not infrequent.

Two-dimensional chromatography for enantiomeric analysis of mitotane and its metabolite o,p'-DDA in patients with adrenocortical carcinoma indicates enantioselective metabolism

Mitotane is a chiral drug used to treat adrenocortical carcinoma, being metabolized to the o,p'-dichlorodiphenyl acetic acid (o,p'-DDA), also a chiral compound. Despite of its therapeutic significance, the overall ratios and enantiomers have not been known. In this study, we analyzed the enantiomers of mitotane and o,p'-DDA in the plasma of patients by a newly developed chiral-phase method employed in two-dimensional chromatography. Important differences were observed in the ratio of (S)/(R)-mitotane, which varied substantially from 1:1.2 to 1:10 whereas the (S)/(R)-o,p'-DDA ratio was relatively conserved, at approximately 2:1. These findings provide evidence for the enantioselective metabolism and provide a method for further analyses of mitotane and metabolites, which can explain the variation in the therapeutic response.

Retrospective Analysis of Prognostic Factors in Pediatric Patients with Adrenocortical Tumor from Unique Tertiary Center with Long-Term Follow-Up

Pediatric adrenocortical tumors (PACTs) represent rare causes of malignancies. However, the south/southeast regions of Brazil are known to have a high incidence of PACTs because of the founder effect associated with a germline pathogenic variant of tumor suppressor gene TP53. We aimed to retrospectively analyze the types of variables among hormone production, radiological imaging, tumor staging, histological and genetic features that were associated with the occurrence of malignancy in 95 patients (71% females) with PACTs from a unique center. The worst prognosis was associated with those aged > 3 years (p < 0.05), high serum levels of 11-desoxicortisol (p < 0.001), tumor weight ≥ 200 g (p < 0.001), tumor size ≥ 5 cm (p < 0.05), Weiss score ≥ 5 (p < 0.05), Wieneke index ≥ 3 (p < 0.001) and Ki67 ≥ 15% (p < 0.05). Furthermore, patients with MacFarlane stage IV had an overall survival rate almost two times shorter than patients with other stages (p < 0.001). Additionally, the subtractions of BUB1B-PINK1 (<6.95) expression (p < 0.05) and IGF-IR overexpression (p = 0.0001) were associated with malignant behavior. These results helped identify patients who are likely to have an aggressive course; further multicenter prospective studies are required to confirm our results. In conclusion, PACTs with these patterns of prognostic factors could be treated using an adjuvant approach that may improve the overall survival in such patients.

Biological response of adrenal carcinoma and melanoma cells to mitotane treatment

A previous case report described an adrenal incidentaloma initially misdiagnosed as adrenocortical carcinoma (ACC), which was treated with mitotane. The final diagnosis was metastatic melanoma of unknown primary origin. However, the patient developed rapid disease progression after mitotane withdrawal, suggesting a protective role for mitotane in a non-adrenal-derived tumor. The aim of the present study was to determine the biological response of primary melanoma cells obtained from that patient, and that of other established melanoma and ACC cell lines, to mitotane treatment using a proliferation assay, flow cytometry, quantitative PCR and microarrays. Although mitotane inhibited the proliferation of both ACC and melanoma cells, its role in melanoma treatment appears to be limited. Flow cytometry analysis and transcriptomic studies indicated that the ACC cell line was highly responsive to mitotane treatment, while the primary melanoma cells showed a moderate response in vitro. Mitotane modified the activity of several key biological processes, including ‘mitotic nuclear division’, ‘DNA repair’, ‘angiogenesis’ and ‘negative regulation of ERK1 and ERK2 cascade’. Mitotane administration led to elevated levels of DNA double-strand breaks, necrosis and apoptosis. The present study provides a comprehensive insight into the biological response of mitotane-treated cells at the molecular level. Notably, the present findings offer new knowledge on the effects of mitotane on ACC and melanoma cells.

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.

The Prognostic Role of CD8+ T Lymphocytes in Childhood Adrenocortical Carcinomas Compared to Ki-67, PD-1, PD-L1, and the Weiss Score

Adrenocortical carcinoma (ACC) is a rare disease among children. Our goal was to identify prognostic biomarkers in 48 primary ACCs from children (2.83 ± 2.3 y; mean age ± SD) by evaluating the tumor stage and outcome for an age of diagnosis before or after 3 years, and association with ACC cluster of differentiation 8 positive (CD8+) cytotoxic T lymphocytes (CD8+-CTL) and Ki-67 immunohistochemical expression (IHC). Programmed death 1(PD-1)/Programmed death-ligand 1 (PD-L1) immunohistochemistry (IHC) in ACC was analyzed in a second, partially overlapping cohort (N = 19) with a similar mean age. All patients and control children were carriers of the germline TP53 R337H mutation. Survival without recurrence for less than 3 years and death unrelated to disease were excluded. Higher counts of CD8+-CTL were associated with patients diagnosed with ACC at a younger age and stage I, whereas a higher percentage of the Ki-67 labeling index (LI) and Weiss scores did not differentiate disease free survival (DFS) in children younger than 3 years old. No PD-1 staining was observed, whereas weakly PD-L1-positive immune cells were found in 4/19 (21%) of the ACC samples studied. A high CD8+-CTL count in ACC of surviving children is compelling evidence of an immune response against the disease. A better understanding of the options for enhancement of targets for CD8+ T cell recognition may provide insights for future pre-clinical studies.

Adrenocortical tumors associated with the TP53 p.R337H germline mutation can be identified during child-care consultations

OBJECTIVE

To evaluate the clinical features associated with adrenocortical hormone overexpression and familial cancer profiling as potential markers for early detection of adrenocortical tumors in children from South and Southeast Brazil.

METHODS

The clinical manifestations and anthropometric measurements of 103 children diagnosed with adrenocortical tumors were analyzed.

RESULTS

Between 1982 and 2011, 69 girls and 34 boys diagnosed with adrenocortical tumors were followed-up for a median time of 9.0 years (0-34 years). Signs of androgen overproduction alone (n=75) or associated with cortisol (n=18) were present in 90.3%. TP53 p.R337H mutation was found in 90.5% of patients. Stages I, II, III, and IV were observed in 45.6%, 27.2%, 19.4%, and 7.8% of patients, respectively. At diagnosis, there were no significant differences in height (p=0.92) and weight (p=0.22) among children with adrenocortical tumors, but children with virilization alone had significantly higher height-for-age Z-scores (0.92±1.4) than children with hypercortisolism alone or combined (-0.32±1,8; p=0.03). The five-year overall survival was 76.7% (SD±4.2). Patients with advanced-stage disease had a significantly worse prognosis than those with limited disease (p<0.001). During follow-up, ten of 55 p.R337H carrier parents developed cancer, whereas none of the 55 non-carriers did.

CONCLUSIONS

Signs of adrenocortical hormone overproduction appear early, even in cases with early-stage. These signs can be identified at the physical examination and anthropometric measurements. In southern Brazil, pediatric adrenocortical tumor is a sentinel cancer for detecting families with germline p.R337H mutation in TP53 gene.

Management and prognosis of adrenocortical tumors in children: can we find out an appropriate points-scoring system to predict prognosis?

BACKGROUND/PURPOSE

Adrenocortical tumors (ACTs) are rare in childhood. There are no recognized criteria to exactly distinguish between benign and malignant forms, or predict prognosis. The incidence of tumor varies across geographic regions or ethnicities, as well as malignant proportion. The aim of this study is to examine a single institution's experience with pediatric ACTs and to validate the prognostic value of the biologic/pathologic criteria of Wienecke.

METHODS

Records of 26 pediatric ACTs between 1994 and 2016 in our center were reviewed retrospectively. The data recorded of each patient included clinical characteristics, treatment, pathologic findings, disease stating, and outcome. Tumors were categorized according to the Wienecke criteria.

RESULTS

All patients underwent primary surgical excision, including negative margins in 20 cases. Stage distribution at diagnosis was: ST I 12, ST II 8, ST III 5, and ST IV 1. According to Wienecke scoring system, 13 cases were <3 criteria, 6 cases were =3 criteria, and 7 cases were >3 criteria. At median follow-up of 34.5 months, 18 patients survived without evidence of disease and 8 patients had lethal outcome. There was a strong association between high Wienecke score and both high stage and adverse outcome.

CONCLUSIONS

Wienecke criteria can be an appropriate points-scoring system to predict prognosis for adrenocortical tumors in children. Complete surgical resection with negative margins is optimal for survival.

Recurrence and mortality prognostic factors in childhood adrenocortical tumors: Analysis from the Brazilian National Institute of Cancer experience

Prognostic markers that can help identifying precocious risk of unfavorable outcomes in patients with childhood adrenocortical tumors (ACTs) are still unclear. This observational and retrospective study aimed to identify clinical and pathology prognostic factors of recurrence and death in a tertiary cancer center population. Clinical, pathology, demographic, staging, and therapy data from patients with childhood ACT (median age: 3.6 years) treated at the Brazilian National Institute of Cancer between 1997 and 2015 were assessed. Univariate and bivariate analyses were used to study the association of clinical and pathology characteristics with recurrence and mortality. Recurrence and disease-related mortality were the main outcomes. Twenty-seven patients were included. Complete tumor resection was performed in 21 cases. The median tumor size was 8.2 cm. Mitotane was the most common adjuvant/palliative therapy (n = 13). Recurrence occurred in 6 patients, after a median time of 7.2 months, and was more common among those with larger tumors (P =.008), higher Weiss score (P =.001), and microscopic tumoral necrosis (P =.002). Ten patients died from the disease. Older age (P =.04), larger tumor size (P =.002), metastatic disease (P =.003), previous recurrence (P =.003), incomplete resection (P =.002), intraoperative tumor spillage (P =.005), higher Weiss score (P =.03), microscopic necrosis (P =.005), and capsular invasion (P =.02) were all associated with increased death risk. Even though complete tumor resection was performed in most cases, a considerable number of cases of childhood ACT resulted in recurrence and death. Early identification of unfavorable outcomes is essential to determine ideal therapy and appropriate surveillance.

Adrenocortical carcinoma: the management of metastatic disease

Adrenocortical cancer is a rare malignancy. While surgery is the cornerstone of the management of localized disease, metastatic disease is hard to treat. Cytotoxic chemotherapy and mitotane have been utilized with a variable degree of benefit and few long-term responses. A growing understanding of the molecular pathogenesis of this malignancy as well as multidisciplinary and multi-institutional collaborative efforts will result in better defined targets and subsequently, effective novel therapies.

Adrenocortical carcinoma

Adrenocortical carcinoma (ACC) is a rare endocrine malignancy, often with an unfavorable prognosis. Here we summarize the knowledge about diagnosis, epidemiology, pathophysiology, and therapy of ACC. Over recent years, multidisciplinary clinics have formed and the first international treatment trials have been conducted. This review focuses on evidence gained from recent basic science and clinical research and provides perspectives from the experience of a large multidisciplinary clinic dedicated to the care of patients with ACC.

Impact of neonatal screening and surveillance for the TP53 R337H mutation on early detection of childhood adrenocortical tumors

PURPOSE

The incidence of pediatric adrenocortical tumors (ACTs) is remarkably high in southern Brazil, where more than 90% of patients carry the germline TP53 mutation R337H. We assessed the impact of early detection of this mutation and of surveillance of carriers.

PATIENTS AND METHODS

Free newborn screening was offered at all hospitals in the state of Paraná. Parents of positive newborns were tested, and relatives in the carrier line were offered screening. Positive newborns and their relatives age < 15 years were offered surveillance (periodic clinical, laboratory, and ultrasound evaluations). ACTs detected by imaging were surgically resected.

RESULTS

Of 180,000 newborns offered screening, 171,649 were screened, and 461 (0.27%) were carriers. As of April 2012, ACTs had been diagnosed in 11 of these carriers but in only two neonatally screened noncarriers (P < .001); six patient cases were identified among 228 carrier relatives age < 15 years (total, 19 ACTs). Surveillance participants included 347 (49.6%) of 699 carriers. Tumors were smaller in surveillance participants (P < .001) and more advanced in nonparticipants (four with stage III disease; two deaths). Neonatally screened carriers also had neuroblastoma (n = 1), glioblastoma multiforme (n = 1), choroid plexus carcinoma (n = 2), and Burkitt lymphoma (n = 1). Cancer histories and pedigrees were obtained for 353 families that included 1,704 identified carriers. ACTs were the most frequent cancer among carrier children (n = 48).

CONCLUSION

These findings establish the prevalence of the TP53 R337H mutation in Paraná state and the penetrance of ACTs among carriers. Importantly, screening and surveillance of heterozygous carriers are effective in detecting ACTs when readily curable.

Impact of early postnatal androgen exposure on voice development

Background

The impact of early postnatal androgen exposure on female laryngeal tissue may depend on certain characteristics of this exposure. We assessed the impact of the dose, duration, and timing of early androgen exposure on the vocal development of female subjects who had been treated for adrenocortical tumor (ACT) in childhood.

Methods

The long-term effects of androgen exposure on the fundamental vocal frequency (F0), vocal pitch, and final height and the presence of virilizing signs were examined in 9 adult (age, 18.4 to 33.5 years) and 10 adolescent (13.6 to 17.8 years) female ACT patients. We also compared the current values with values obtained 0.9 years to 7.4 years after these subjects had undergone ACT surgery, a period during which they had shown normal androgen levels.

Results

Of the 19 subjects, 17 (89%) had been diagnosed with ACT before 4 years of age, 1 (5%) at 8.16 years, and 1 (5%) at 10.75 years. Androgen exposure (2 to 30 months) was sufficiently strong to cause pubic hair growth in all subjects and clitoromegaly in 74% (14/19) of the subjects, but did not reduce their height from the target value. Although androgen exposure induced a remarkable reduction in F0 (132 Hz) and moderate pitch virilization in 1 subject and partial F0 virilization, resulting in F0 of 165 and 169 Hz, in 2 subjects, the majority had normal F0 ranging from 189 to 245 Hz.

Conclusions

Female laryngeal tissue is less sensitive to androgen exposure between birth and adrenarche than during other periods. Differential larynx sensitivity to androgen exposure in childhood and F0 irreversibility in adulthood are age-, concentration-, duration-, and timing-dependent events that may also be affected by exposure to inhibitory or stimulatory hormones. Further studies are required to better characterize each of these factors.

Identity by descent mapping of founder mutations in cancer using high-resolution tumor SNP data

Dense genotype data can be used to detect chromosome fragments inherited from a common ancestor in apparently unrelated individuals. A disease-causing mutation inherited from a common founder may thus be detected by searching for a common haplotype signature in a sample population of patients. We present here FounderTracker, a computational method for the genome-wide detection of founder mutations in cancer using dense tumor SNP profiles. Our method is based on two assumptions. First, the wild-type allele frequently undergoes loss of heterozygosity (LOH) in the tumors of germline mutation carriers. Second, the overlap between the ancestral chromosome fragments inherited from a common founder will define a minimal haplotype conserved in each patient carrying the founder mutation. Our approach thus relies on the detection of haplotypes with significant identity by descent (IBD) sharing within recurrent regions of LOH to highlight genomic loci likely to harbor a founder mutation. We validated this approach by analyzing two real cancer data sets in which we successfully identified founder mutations of well-characterized tumor suppressor genes. We then used simulated data to evaluate the ability of our method to detect IBD tracts as a function of their size and frequency. We show that FounderTracker can detect haplotypes of low prevalence with high power and specificity, significantly outperforming existing methods. FounderTracker is thus a powerful tool for discovering unknown founder mutations that may explain part of the "missing" heritability in cancer. This method is freely available and can be used online at the FounderTracker website.

Molecular epidemiology of adrenocortical tumors in southern Brazil

The high frequency of TP53 R337H carriers in southern Brazil is responsible for the highest known incidence of childhood adrenocortical tumor (ACT). Our aims were to examine other contributing mutations, age-related risk factors, epidemiological differences in ACT and to shed light on a method for increasing the survival rate of children. The fetal zone of the adrenal cortex is believed to be one of the tissues most susceptible to adenoma or carcinoma formation due to loss of p53 function. The founder germline R337H mutation is found in 95% of ACTs of young children, a much greater proportion than in adults. Despite intense educational campaigns about the high incidence of ACT in Paraná State, advanced cases remain common. Four advanced ACT cases (4/5) were admitted to a single institution in the first 6months of 2011 in Paraná State, none of the families knew about ACT, and 2 reported no familial cancer syndrome. Curative resection is possible when a small ACT is detected early.

The International Pediatric Adrenocortical Tumor Registry initiative: contributions to clinical, biological, and treatment advances in pediatric adrenocortical tumors

Adrenocortical tumor (ACT), a rare tumor with a heterogeneous presentation, incompletely understood pathogenesis, and generally poor prognosis, occurs in 1-2 people per million and is even more uncommon in the pediatric population. Such rare cancers are a challenge to clinical practice. Exchange of experience, information, and data on rare cancers is lacking, and outcomes for these rare cancers could be improved through the establishment of an international registry. The establishment of the International Pediatric Adrenocortical Tumor Registry (IPACTR) in 1990 by the St. Jude Children's Research Hospital International Outreach Program offered a new opportunity to collect clinical and laboratory features, treatment practices, and outcome data for children with ACT, research this disease, and systematically investigate how to improve patient outcomes. These efforts will improve the availability of information for both patients and the medical community.

TP53-Associated Pediatric Malignancies

Although the majority of pediatric malignancies express wild-type p53, it is well established that germline TP53 mutations or functional inactivation of this pathway by other means contribute to childhood cancer. Epidemiology studies have revealed the existence of diverse inherited mutant TP53 alleles that display different levels of tumor suppressor activity, which correlate with cancer risk in terms of penetrance, age of onset, and tumor types. In this monograph, the authors describe those childhood cancers associated with functional inactivation of TP53 focusing on adrenocortical carcinoma as a model for tissues that are highly sensitive to loss of p53 activity.

Pediatric adrenocortical tumors: morphological diagnostic criteria and immunohistochemical expression of matrix metalloproteinase type 2 and human leucocyte-associated antigen (HLA) class II antigens. Results from the Italian Pediatric Rare Tumor (TREP) Study project

Pediatric adrenocortical tumors are neoplasms that only rarely occur in pediatric patients. Their clinical behavior is often unpredictable, and the histologic criteria of malignancy used in adults are not always useful in children. The aim of this study was to validate the prognostic value of the pathologic criteria of Wieneke et al and to evaluate the potential prognostic expression of matrix metalloproteinase 2 and human leucocyte-associated antigen (HLA) class II antigens in a series of 20 pediatric patients affected by adrenocortical tumors, who were enrolled in the Italian Pediatric Rare Tumor (TREP) Study between 2000 and 2007. The age range was 0 to 17.5 years (mean, 7.28 years) with a male-female ratio of 1:2. The mean follow-up was 64.4 months. The histologic diagnoses were reviewed, and the cases were classified using the criteria for malignancy proposed by Wieneke et al. The immunohistochemical expression of matrix metalloproteinase 2 and HLA class II antigens was scored by semiquantitative analysis and compared with the clinicopathologic parameters and outcome. Based on the scoring system of Wieneke et al, 7 tumors were classified as malignant; 12 tumors, as benign; and only 1 tumor, with "unpredictable behavior." In all cases, the clinical behavior was consistent with the pathologic criteria of Wieneke et al. Notably, areas of regressive myxoid changes, not included among the criteria of Wieneke et al, were observed in all but 1 case of malignant tumors and only in 2 cases of benign tumors. Matrix metalloproteinase 2 was focally to diffusely expressed in all malignant and in most benign tumors. HLA class II antigens immunoreactivity was absent in all benign tumors and restricted to rare isolated cells in most malignant tumors. Our findings confirm that the pathologic scoring system of Wieneke et al is a simple and reproducible diagnostic tool to predict prognosis in pediatric adrenocortical tumors. Unlike in their adult counterpart, the expression of matrix metalloproteinase 2 or the loss of HLA class II antigens does not discriminate between benign and malignant tumors in children. Although pediatric adrenocortical tumors seem to be similar histologically to their adult counterparts, it is likely that they have distinctive molecular features.

Adrenocortical carcinoma: a clinician's update

Adrenocortical carcinoma is a rare heterogeneous neoplasm with an incompletely understood pathogenesis and a poor prognosis. Previous studies have identified overexpression of insulin-like growth factor 2 (IGF-2) and constitutive activation of β-catenin as key factors involved in the development of adrenocortical carcinoma. Most patients present with steroid hormone excess, for example Cushing syndrome or virilization, or abdominal mass effects, but a growing proportion of patients with adrenocortical carcinoma (currently >15%) is initially diagnosed incidentally. No general consensus on the diagnostic and therapeutic measures for adrenocortical carcinoma exists, but collaborative efforts, such as international conferences and networks, including the European Network for the Study of Adrenal Tumors (ENSAT), have substantially advanced the field. In patients with suspected adrenocortical carcinoma, a thorough endocrine and imaging work-up is recommended to guide the surgical approach aimed at complete resection of the tumor. To establish an adequate basis for treatment decisions, pathology reports include the Weiss score to assess malignancy, the resection status and the Ki67 index. As recurrence is frequent, close follow-up initially every 3 months is mandatory. Most patients benefit from adjuvant mitotane treatment. In metastatic disease, mitotane is the cornerstone of initial treatment, and cytotoxic drugs should be added in case of progression. Results of a large phase III trial in advanced adrenocortical carcinoma are anticipated for 2011 and will hopefully establish a benchmark therapy. New targeted therapies, for example, IGF-1 receptor inhibitors, are under investigation and may soon improve current treatment options.

Genetics and genomics of childhood adrenocortical tumors

Adrenocortical tumors in children are usually diagnosed because of signs of virilization and their prognosis is poor. They possess several distinct pathological features compared to adrenocortical tumors in adults and have an exceptional prevalence in southern Brazil, where they are nearly invariably linked to the presence of a germline specific TP53 (R337H) mutation. Other important factors in childhood adrenocortical tumor pathogenesis are overexpression of the Steroidogenic Factor-1 transcription factor and imprinting defects in the 11p15 genomic region, causing overexpression of Insulin-like Growth Factor-2. Genomic studies have revealed the prognostic relevance of the expression of some Major Histocompatibility Complex genes and the deregulation of the Insulin-like Growth Factor/mammalian Target Of Rapamycin pathway by microRNAs in these tumors. Our hope is that these findings will constitute the basis for the development of novel therapies that will be more active against these tumors and less toxic for the patients.

Increased incidence of choroid plexus carcinoma due to the germline TP53 R337H mutation in southern Brazil

Background

Choroid plexus carcinomas (CPC) are rare tumors predominantly found in children. Given the high frequency of the germline R337H mutation in the TP53 gene in southern Brazil, we have evaluated the frequency of the R337H mutation in families with CPC in children.

Methodology/Principal Findings

The present series included 29 patients that were admitted to the same institution from 1992 to 2010, including 22 children with CPC (0.08–13.6 years of age at diagnosis) and 7 children with papilloma of the choroid plexus (Pp; 0.5–9.8 years of age). Surgical resection was possible in 28 children. Blood and/or tumor DNA was extracted and analyzed using PCR-RFLP and results were confirmed by sequencing 240 bp of the TP53 exon 10. The patients, all parents, and some relatives submitted samples for blood DNA analysis. In addition, we have also examined the presence of the mutation in DNA from paraffin-embedded tumor samples to evaluate loss of heterozygosity. We found 63.3% (14/22) of the CPC patients positive for the germline R337H mutation; CPC samples were either heterozygous (n = 7), lost only the wild-type (n = 4), or only the R337H copy (n = 2). One CPC sample was not available. All Pp cases (7/7, 100%) were negative for R337H. Cure (>5 years survival free of disease) was observed in 18.1% of the CPC cases with the R337H mutation (2/11), 71.4% of the Pp (5/7), and 25% of CPC cases negative for the R337H mutation (2/8). Family history of cancer (with 2 or more cancer cases) was exclusively identified on the parental side segregating the R337H mutation, and 50% (7/14) of them were compatible with Li-Fraumeni-like syndrome.

Significance

Our results show for the first time that the R337H TP53 mutation is responsible for 63% of the CPC cases in children, suggesting a higher incidence of CPC in southern Brazil.

Cancer incidence among children and adolescents in Brazil: first report of 14 population-based cancer registries

The Brazilian Population-Based Cancer Registry (PBCR) was started in 1967; today there are 20 PBCRs in Brazil. We report the first descriptive analysis of the incidence of childhood cancer based on data from 14 PBCRs, corresponding to 15% of the child and adolescent population in Brazil. Data were obtained from registry databases, including information on population coverage and data quality indicators. The International Classification of Childhood Cancer was used. Age-adjusted rates were calculated by world population. Incidence by cancer registry, age, sex, and cancer type were calculated per 1,000,000 children. Age-adjusted rates per 1,000,000 children/adolescents ranged from 92 to 220 among the 14 PBCRs. The principal groups of cancers were leukemia, lymphoma and central nervous tumors. The median incidence rate of childhood cancer in the 14 PBCRs was 154.3 per million; children 1-4 years of age had the highest incidence rates. The Brazilian PBCRs provide important information about pediatric cancer incidence in an emerging country. The observed incidence rates of childhood leukemia were similar to previous reported rates, and the age-specific incidence rates of retinoblastoma (0-4 years of age) were higher than those for developed countries. These data can be used as baseline incidence rates of childhood and adolescent cancer in Brazil in future epidemiological studies.

Outcome of adrenocortical tumors in children

PURPOSE

This study reviews adrenocortical tumors in children to determine factors that significantly affect outcome.

METHODS

An institutional review board-approved retrospective review from 1976 to 2005 identified 23 patients younger than 19 years old with histologic confirmation of adrenocortical carcinoma (ACC) and adenomas.

RESULTS

The mean age of the 23 children was 9.0 +/- 1.6 years; girls predominated (female-to-male ratio = 1.9:1) as did cancers (ACC 16, adenoma 7); tumor hormone production (74%); and advanced stage for disease (66%). All malignancies were more than 2.5 cm. Adrenalectomy, including en bloc resection of adjacent structures (35%) achieved grossly negative margins in 70% of patients. Three patients received chemotherapy or chemoradiation as primary treatment without surgery. There was no perioperative mortality; morbidity was 10% (pneumothorax, acute renal failure, chylous ascites, and thrombocytosis). Surgical cure without adjuvant therapy was achieved for all adenomas and ACC stages I and II. For ACC stage III and IV, median survival was 21 months, 5-year survival was 0%. All advanced-staged ACC received adjuvant therapy. Surgically negative margins conferred a survival advantage.

CONCLUSIONS

Children, especially females with ACC present with large advanced-staged tumors. Surgically negative margins with or without en bloc resection improves survival. The high percentage of children with functioning tumors suggests earlier detection is possible.

Increased steroidogenic factor-1 dosage triggers adrenocortical cell proliferation and cancer

Steroidogenic factor-1 (SF-1/Ad4BP; NR5A1), a nuclear receptor transcription factor, has a pivotal role in adrenal and gonadal development in humans and mice. A frequent feature of childhood adrenocortical tumors is SF-1 amplification and overexpression. Here we show that an increased SF-1 dosage can by itself augment human adrenocortical cell proliferation through concerted actions on the cell cycle and apoptosis. This effect is dependent on an intact SF-1 transcriptional activity. Gene expression profiling showed that an increased SF-1 dosage regulates transcripts involved in steroid metabolism, the cell cycle, apoptosis, and cell adhesion to the extracellular matrix. Consistent with these results, increased SF-1 levels selectively modulate the steroid secretion profile of adrenocortical cells, reducing cortisol and aldosterone production and maintaining dehydroepiandrosterone sulfate secretion. As a model to understand the mechanisms of transcriptional regulation by increased SF-1 dosage, we studied FATE1, coding for a cancer-testis antigen implicated in the control of cell proliferation. Increased SF-1 levels increase its binding to a consensus site in FATE1 promoter and stimulate its activity through modulation of the recruitment of specific cofactors. On the other hand, sphingosine, which can compete with phospholipids for binding to SF-1, had no effect on the SF-1 dosage-dependent increase of adrenocortical cell proliferation and expression of the FATE1 promoter. In mice, increased Sf-1 dosage produces adrenocortical hyperplasia and formation of tumors expressing gonadal markers (Amh, Gata-4), which originate from the subcapsular region of the adrenal cortex. Gene expression profiling revealed that genes involved in cell adhesion and the immune response and transcription factor signal transducer and activator of transcription-3 (Stat3) are differentially expressed in Sf-1 transgenic mouse adrenals compared with wild-type adrenals. Our studies reveal a critical role for SF-1 dosage in adrenocortical tumorigenesis and constitute a rationale for the development of drugs targeting SF-1 transcriptional activity for adrenocortical tumor therapy.

Mitotane associated with cisplatin, etoposide, and doxorubicin in advanced childhood adrenocortical carcinoma: mitotane monitoring and tumor regression

PURPOSE

To define a mitotane dose for pediatric patients with adrenocortical cancer (ACC) that maintains therapeutic plasma levels (TL) between 14 and 20 microg/mL and to verify its antitumor efficacy in association with 8 cycles of cisplatin, etoposide, and doxorubicin (CED).

METHODS

Powdered mitotane was dissolved in a medium chain triglyceride oil and administered to 11 children with ACC (2.4 to 15.4 y of age); an initial low dose was increased to 4 g/m2/d. Ten of the 11 children had a germline TP53 R337H mutation. Mitotane plasma levels were determined using high-performance liquid chromatography.

RESULTS

The mitotane dose to maintain TL in 7 patients ranged from 1.0 to 5.3 g/m2/d. Six children reached mitotane levels of 10 microg/mL in 3.6 months (1.5 to 5.0 mo), whereas 5 children took 8 months (6.5 to 12.5 mo). Minor to partial tumor remission was found in 5 patients (<1 y) and complete remission was found in 2 patients. Of the 3 patients who are alive at the time of report, 1 patient has been without disease for 16 months, and 2 patients have progressive disease. All patients had recurrent metastatic disease (2 to 9 times). Mitotane toxic effects were nausea, diarrhea, vomiting, neurologic alterations, gynecomastia, a rare case of hypertensive encephalopathy, and CED-related hematologic toxic effects.

CONCLUSIONS

Mitotane daily dose to maintain TL is variable and monitoring should start 1.5 months after the beginning of treatment. CED combined with mitotane is the best available pharmacologic treatment for ACC, but further studies are required to characterize different profiles of therapeutic response.