The activating TERT promoter mutation C228T is recurrent in subsets of adrenal tumors

The telomerase reverse transcriptase gene (TERT) encodes the reverse transcriptase component of the telomerase complex, which is essential for telomere stabilization and cell immortalization. Recent studies have demonstrated a transcriptional activation role for the TERT promoter mutations C228T and C250T in many human cancers, as well as a role in aggressive disease with potential clinical applications. Although telomerase activation is known in adrenal tumors, the underlying mechanisms are not established. We assessed C228T and C250T TERT mutations by direct Sanger sequencing in tumors of the adrenal gland, and further evaluated potential associations with clinical parameters and telomerase activation. A total of 199 tumors were evaluated, including 34 adrenocortical carcinomas (ACC), 47 adrenocortical adenomas (ACA), 105 pheochromocytomas (PCC; ten malignant and 95 benign), and 13 abdominal paragangliomas (PGL; nine malignant and four benign). TERT expression levels were determined by quantitative RT-PCR. The C228T mutation was detected in 4/34 ACCs (12%), but not in any ACA (P=0.028). C228T was also observed in one benign PCC and in one metastatic PGL. The C250T mutation was not observed in any case. In the ACC and PGL groups, TERT mutation-positive cases exhibited TERT expression, indicating telomerase activation; however, since expression was also revealed in TERT WT cases, this could denote additional mechanisms of TERT activation. To conclude, the TERT promoter mutation C228T is a recurrent event associated with TERT expression in ACCs, but rarely occurs in PGL and PCC. The involvement of the TERT gene in ACC represents a novel mutated gene in this entity.

Identification of a CpG island methylator phenotype in adrenocortical carcinomas

PURPOSE

DNA methylation is a mechanism for gene expression silencing in cancer. Limited information is available for adrenocortical tumors. Abnormal methylation at the IGF2/H19 locus is common in adrenocortical carcinomas. Our aim was to characterize the methylation in adrenocortical carcinomas at a whole-genome scale and to assess its clinical significance and its impact on gene expression.

EXPERIMENTAL DESIGN

Methylation patterns of CpG islands in promoter regions of 51 adrenocortical carcinomas and 84 adenomas were studied by the Infinium HumanMethylation27 Beadchip (Illumina, San Diego, CA). Methylation of 33 genes was studied by methylation-specific multiplex ligation-dependent probe amplification (MRC-Holland, Amsterdam, The Netherlands) in 15 carcinomas. Gene expression data were available for 87 tumors from a previous study (HG-U133Plus2.0 AffymetrixGeneChip; Affymetrix, Santa Clara, CA). Clinical information, including patient features and survival, were available for all tumors.

RESULTS

Methylation was higher in carcinomas than in adenomas (t test P = 3.1 × 10(-9)). Unsupervised clustering of DNA methylation profiles identified two groups of carcinomas, one with an elevated methylation level, evoking a CpG island methylator phenotype (CIMP). The subgroup of hypermethylated carcinomas was further divided in two subgroups, with different levels of methylation (CIMP-high and CIMP-low). This classification could be confirmed by methylation-specific multiplex ligation-dependent probe amplification. Hypermethylation was associated with a poor survival (Cox model P = 0.02). The transcriptome/methylation correlation showed 1741 genes (of 12,250) negatively correlated; among the top genes were H19 and other tumor suppressors (PLAGL-1, G0S2, and NDRG2).

CONCLUSIONS

This genome-wide methylation analysis reveals the existence of hypermethylated adrenocortical carcinomas, with a poorer prognosis. Hypermethylation in these tumors is important for silencing specific tumor suppressor genes.

Retroperitoneal adrenal-sparing surgery for the treatment of Cushing's syndrome caused by adrenocortical adenoma: 8-year experience with 87 patients

BACKGROUND

The objective of this study was to present our 8-year experience with partial adrenalectomy via the retroperitoneal approach for the treatment of Cushing's adenoma.

METHODS

A total of 93 patients who underwent adrenal surgery for Cushing's adenoma from March 2003 to December 2010 were enrolled in this study. Preoperative, intraoperative, and postoperative variables were reviewed from the database. Student's t test was used to analyze the continuous data, and the χ(2) test was used to analyze the categoric data. A value of p < 0.05 was considered statistically significant.

RESULTS

Adrenal-sparing surgery was performed in 87 cases (31 by open surgery, 56 by retroperitoneal laparoscopy). Six patients underwent open/laparoscopic total adrenalectomy because of recurrent disease or a large size. The cure rate in our series was 97.8%. Hypertension resolved in 34 of 64 patients (53.1%), diabetes in 7 of 27 patients (25.9%) and obesity in 28 of 48 patients (58.3%). One patient died during the postoperative period. The intraoperative complication rate for the open surgery group was significantly higher than that for the retroperitoneal laparoscopy group (9.1 vs. 1.7%).

CONCLUSIONS

The retroperitoneal approach is reliable and safe for treating Cushing's syndrome. The laparoscopic technique can decrease the prevalence of intraoperative complications. Retroperitoneal laparoscopic partial adrenalectomy can be performed with extremely low morbidity and achieves an excellent outcome, although death may occur during the postoperative period in high-risk patients. Postoperative management plays an important role in the surgical treatment of Cushing's syndrome.

Dysregulation of microRNAs in adrenocortical tumors

MicroRNAs (miRNAs) are short non-coding RNAs that are involved in the epigenetic regulation of cellular processes. Different malignancies are often associated with the deregulation of specific sets of miRNAs. The prognosis of adrenocortical cancers (ACCs) is very poor as compared to adrenocortical adenomas (ACAs), and even within ACCs there are cases with better disease specific survival. An improved understanding of the pathobiology of this disease will therefore be useful in facilitating better management of ACCs as well as distinguishing high risk versus low risk subgroups. One third of coding genes are regulated by miRNAs and therefore changes in miRNA expression may be associated with cancer development and progression. In this review we summarize the current understanding of miRNAs in adrenocortical tumors, and highlight their potential in differentiating between ACCs and ACAs, risk stratification and prognosis.

Laparoscopic adrenalectomy for large solid cortical tumours--is it appropriate?

BACKGROUND

Laparoscopic adrenalectomy, the procedure of choice for small benign adrenal tumours, is also used for large tumours. Our study aims to assess the outcome of large adrenal tumours laparoscopically resected.

METHODS

All patients with laparoscopic adrenalectomy performed in between 2002 and 2009, without preoperative or intraoperative malignant characteristics, were reviewed. Clinical, biochemical and CT follow-up data were reviewed for evidence of recurrent disease.

RESULTS

Fifty patients underwent laparoscopic adrenalectomies in our unit, 18 of them having solid cortical tumours > or = 7 cm without preoperative or intraoperative malignant features: 6 Cushing's syndrome tumours, 8 non-secreting tumours, 4 aldosteronomas. The mean age of the patients was 46.89 years (range 22-64 years), and the mean tumour size 7.57 cm (range 7-9.1 cm). Histology identified 10 cortical adenomas, 4 malignant tumours, and 4 indeterminate tumours. The mean - follow-up was 28.94 months (range 4-58 months). Three patients died of systemic recurrent disease (liver and lung metastases) at 12, 19 and 21 month, respectively, after operation. One patient underwent a left hepatectomy for liver metastases, 33 months postoperatively. Fourteen patients have no evidence of recurrence.

CONCLUSIONS

Adrenal tumours > or = 7 cm without pre- or intraoperative evidence of malignancy are resectable laparoscopically. This approach is unlikely to worsen the long-term outcome. The mortality is related to the malignancy.

Results of adrenal surgery. Data of a Spanish National Survey

PURPOSE

Given the availability of laparoscopy and the rising detection of incidentalomas, indications for adrenalectomy may be changing. The Endocrine Surgery Section of the Spanish Association of Surgeons designed a survey to assess its indications, techniques, and results in Spanish Surgical Departments.

METHODS

Collected data included hospital and department type, yearly hospital volume of procedures; location studies and preoperative preparation performed, indications, surgical approach and instruments used, and results in terms of morbidity and overall hospital stay. The analysis included a comparison between results of high- or low-volume centers and surgeons, using the Student's t test for quantitative and chi-square test for qualitative variables. Level of significance was set at 0.05.

RESULTS

Nineteen centers returned the questionnaire, including 155 adrenalectomies performed in 2008. Most frequent indications were pheochromocytoma (23.2%), aldosteronoma (16.7%), incidentaloma (12.2%), metastasis (10.3%), Cushing adenoma (9.6%), and carcinoma (3.8%). Laparoscopy was performed in 83.9% of cases (9.4% required conversion to laparotomy). Four patients required urgent reoperation. Average hospital stay: 4.6 days (3.3 days after laparoscopy, 7 days after laparotomy). High-volume centers had a greater proportion of laparoscopically treated cases (p = 0.008), more malignant lesions treated (p = 0.03), a shorter overall stay (p < 0.0001), and a shorter stay after laparotomic adrenalectomy (p = 0.01). High-volume surgeons had similar results, and less in-hospital morbidity (p = 0.02).

CONCLUSIONS

In Spain, adrenalectomy is performed in hospitals of varying complexity. Laparoscopic approach is the rule, with good results in terms of morbidity and stay. High-volume centers and surgeons had best results in terms of use of minimally invasive surgery and hospital stay.

[The long-term results of the dynamic observation of patients with adrenal gland adenomas]

The authors demonstrate the results of many years of observing patients with hormone-inactive adrenal gland adenomas. The subjects were 80 patients observed during 8 months to 12 years. The study shows that slow growth is generally typical of these adenomas. In 15% of patients an average growth of 1 mm/year was noted; this growth did not exceed 10 mm throughout the whole period of observation. The researchers also observed changes in the clinical symptoms and hormonal parameters over time. The study demonstrates that long existence of adenomas do not aggravate the clinical course of arterial hypertension and diabetes mellitus, and do not express any hormonal activity. The study established more precise indications to dynamic observation and its algorithm.

Adrenocortical Tumors in Brazilian Children: Immunohistochemical Markers and Prognostic Factors

Context.—The behavior of adrenocortical tumors (ACTs) is usually difficult to establish in childhood, and the role of immunomarkers in predicting outcome has not yet been elucidated.

Objective.—To investigate the relationship between clinical, pathologic, and immunohistochemical findings and prognosis in a series of children with ACTs.

Patients and Methods.—Clinical data were evaluated retrospectively in 33 children with ACTs, including age at diagnosis, sex, time between first symptoms and diagnosis, clinical signs and symptoms, tumor position, and follow-up. Histologic sections were reviewed, each tumor was classified, and staging was performed according to previously published criteria. Immunohistochemical analysis of p53, Ki-67, c-Erb-B2, and Bcl-2 was performed according to previously published techniques.

Results.—Sixty-four percent (n = 21) of the patients were female, and the age at diagnosis in the cohort ranged from 2 to 96 months. Virilization alone affected 70% (n = 23) of the patients, and 18 patients had stage 1 disease, 9 had stage 2 disease, and 3 each had stage 3 and stage 4 disease. Female sex and stage 1 and stage 2 disease were associated with good outcome. None of the histopathologic criteria evaluated correctly predicted outcome. Only tumors with a volume exceeding 200 mL were associated with malignant behavior. Because only a small number of tumors expressed the antigens, results of these immunohistochemical tests were considered inconclusive.

Conclusion.—In this sample of pediatric ACTs, the clinical and surgical parameters are the most important prognostic factors, while the immunohistochemical markers evaluated were not predictive of outcome.

Surgical management of adrenal gland tumors with and without associated tumor thrombi in dogs: 40 cases (1994-2001)

OBJECTIVE

To compare pathologic findings and results of adrenalectomy for adrenal gland tumors in dogs with and without vena caval tumor thrombi.

DESIGN

Retrospective study.

ANIMALS

40 dogs with adrenal gland tumors.

PROCEDURE

Medical records were examined. An exact logistic regression analysis was used to evaluate associations between tumor type or right-sided versus left-sided tumor involvement and development of caval tumor thrombi and associations between tumor thrombi, tumor type, or right- versus left-sided location and perioperative complications and mortality rate. Survival was compared between dogs with and without tumor thrombi.

RESULTS

Caval thrombi were detected in 25% of dogs, including 3 of 28 (11%) dogs with an adrenocortical tumor and 6 of 11 dogs with a pheochromocytoma. A caval tumor thrombus was detected in 6 of 17 right-sided and 4 of 20 left-sided tumors. Sensitivity and specificity of abdominal ultrasonography for detection of caval thrombi were 80 and 90%, respectively. Intraoperative and postoperative complications developed in 15 and 51% of dogs, respectively. The mortality rate was 22%. There were no significant differences in perioperative morbidity and mortality rates between dogs with and without tumor thrombi.

CONCLUSIONS AND CLINICAL RELEVANCE

Caval thrombi associated with adrenal gland tumors are amenable to adrenalectomy and thrombectomy without significantly increased perioperative morbidity and mortality rates, assuming the surgeon is experienced in appropriate techniques.

Pathologic features and expression of insulin-like growth factor-2 in adrenocortical neoplasms

We analyzed a series of adrenocortical neoplasms to compare the clinicopathologic features and the expression of insulin-like growth factor-2 (IGF-2) in adrenocortical adenomas and carcinomas. IGF-2 is a growth factor commonly expressed in many tumors including adrenal cortical and medullary neoplasms. Formalin-fixed paraffin-embedded tissues from 64 adrenocortical adenomas and 67 adrenocortical carcinomas were analyzed. The carcinomas were histologically graded from 1 to 4 based on mitotic activity and necrosis. Tumor weight, size, and follow-up information were obtained by chart review. Expression of IGF-2 was detected by immunohistochemistry with the avidin-biotin-peroxidase complex method and a monoclonal antibody against IGF-2. Adrenocortical carcinomas were larger (mean: 13.1 cm, 787 g) than adenomas (mean: 4.2 cm, 52 g) (p < 0.001). Inpatients with adrenocortical carcinomas, high tumor grade (3 or 4) (p = 0.01) was associated with decreased survival. Expression of IGF-2 was higher in adrenocortical carcinomas than in adenomas (p < 0.001). These results show that tumor size and weight along with expression of IGF-2 protein are useful features to assist in distinguishing between adrenocortical adenomas and carcinomas, and that high tumor grade is a predictor of survival in adrenocortical carcinomas. However, single immunohistochemical markers such as IGF-2 or single histopathologic features cannot by themselves separate adrenocortical adenomas from carcinomas, and a combination of clinical, gross, and microscopic features are needed to establish the diagnosis in difficult cases.

Surgical treatment of adrenocortical tumors: 21 cases (1990-1996)

Twenty-four adrenocortical tumors were surgically removed from 21 dogs. Histopathological examination confirmed 18 carcinomas and six adenomas. Four dogs died in the perioperative period. Fifteen of the 17 dogs that survived the perioperative period had long-term resolution of their clinical signs. Two dogs with incompletely resected tumors were treated with mitotane to control their clinical signs. Overall median Kaplan-Meier life-table survival for dogs with carcinomas was 778 days (range, one to 1,593 days). Median survival for dogs with adenomas was not reached (range, 11 to 730 days). Histopathological diagnosis, histopathological cellular features, age of the dog, and tumor size were not prognostic of outcome.

[Conventional operation for therapy of incidentaloma]

AIM

The increasing detection rate of incidentalomas imposes not only the question about the necessity of treatment but also with introduction of laparoscopic adrenalectomy the question about operative strategy. Own patients and literature are analysed and discussed.

PATIENTS

Between 1985 and 1996 203 patients have been operated on for adrenal disease including 21 patients with incidentaloma.

RESULTS

Biochemical analysis revealed latent hormonal activity in 9 patients. All patients were operated conventionally. Pathohistology demonstrated 1 adrenal carcinoma, 9 adrenocortical adenomas, 2 myelolipomas, 2 adrenal cysts, 2 nodular hyperplasias and 5 pheochromocytomas. Postoperative morbidity was 5% and mortality 0%.

CONCLUSION

Small and hormonally latent active tumors can be operated laparoscopically or conventionally via dorsal approach. In case of suspected malignancy conventional operation is the more reliable procedure.

Adrenal cortical neoplasms. A study of 56 cases

Fifty-six cases of adrenal cortical neoplasm with a minimum of 5 years follow-up are presented: 48 carcinomas and 8 adenomas. Adenomas typically had a maximal mitotic rate of fewer than 2 mitotic figures per 10 high-power fields (all cases), a prominent small nest growth pattern (7 cases), predominantly clear or foamy cytoplasm (6 cases), and no tumor necrosis (all cases), whereas carcinomas were characterized by at least 4 mitotic figures (often many more) per 10 high-power fields in the most active area (all cases), lack of a significant small nest growth pattern component (45 cases--solid or trabecular growth most common), at least a considerable proportion of cells with eosinophilic cytoplasm (all cases), and tumor necrosis (45 cases). Carcinomas were almost always larger than adenomas, but two adenomas (5.9 cm and 7 cm) overlapped in size with the four smallest carcinomas (5.5 cm, 6 cm, 7 cm, and 7 cm, respectively). The patients with adenomas were older on the average than those with carcinomas (median 58 years, range 31-71 years versus median 41 years, range 5 months-66 years). Two adenomas and 19 carcinomas were functional. No patient with adenoma had recurrence of tumor after excision, whereas all but nine carcinoma patients died of tumor, after 1 to 183 months. Among carcinoma patients, survival was significantly shorter when distant metastases were manifest at diagnosis (P = .0003). There was a trend toward shorter survival with higher mitotic rates and functional tumors, but neither these nor any other parameter had a statistically significant relationship to survival or tumor behavior when presence/absence of metastases at diagnosis was taken into account.