Florbela Ferreira

Molecular characterization of parathyroid tumors from two patients with hereditary colorectal cancer syndromes

The tumor suppressor adenomatous polyposis coli (APC) has recently been implicated in parathyroid development. We here report clinical, histopathological and molecular investigations in parathyroid tumors arising in two patients; one familial adenomatous polyposis (FAP) syndrome patient carrying a constitutional APC mutation, and one Lynch syndrome patient demonstrating a germline MLH1 mutation as well as a non-classified, missense alteration of the APC gene. We sequenced the entire APC gene in tumor and constitutional DNA from both cases, assessed the levels of APC promoter 1A and 1B methylation by bisulfite Pyrosequencing analysis and performed immunohistochemistry for APC and parafibromin. In addition, copy number analysis regarding the APC gene on chromosome 5q21-22 was performed using qRT-PCR. Histopathological workup confirmed both tumors as parathyroid adenomas without signs of malignancy or atypia. No somatic mutations or copy number changes for the APC gene were discovered in the tumors; however, in both cases, the APC promoter 1A was hypermethylated while the APC promoter 1B was unmethylated. APC promoter 1B-specific mRNA and total APC mRNA levels were higher than in normal parathyroid samples. Immunohistochemical analyses revealed strong APC protein immunoreactivity and positive parafibromin expression in both parathyroid tumors. Absence of additional somatic APC mutations and copy number changes in addition to the positive APC immunoreactivity obtained suggest that the tumors arose without biallelic inactivation of the APC tumor suppressor gene. The finding of an unmethylated APC promoter 1B and high APC 1B mRNA levels could explain the maintained APC protein expression. Moreover, the findings of positive parafibromin and APC immunoreactivity as well as a low MIB-1 proliferation index and absence of histopathological features of malignancy/atypical adenoma indicate that the parathyroid adenomas arising in these patients did not harbor malignant potential.

Rare and severe complications of congenital adrenal hyperplasia due to 21-hydroxylase deficiency: a case report

IntroductionWe report the case of a patient with classical congenital adrenal hyperplasia due to 21-hydroxylase deficiency who presented with unusual anatomical and biochemical features, namely massively enlarged adrenal glands, adrenogenital rest tissue and an unexpected endocrine profile. The contribution of the adrenocortical cells in the adrenals and testicles was determined by a cosyntropin stimulation test before and after adrenalectomy. To the best of our knowledge this is the first report of such a case in the literature.Case presentationA 35-year-old Caucasian man was admitted to the emergency room with an Addisonian crisis. He had been diagnosed with congenital adrenal hyperplasia in the neonatal period. He acknowledged poor adherence to treatment and irregular medical assistance. Physical examination revealed marked cutaneous and gingival hyperpigmentation, hypotension, and hard nodules in the upper pole of both testicles. Blood analysis showed mild anemia and hyponatremia and no evidence of acute infection. Endocrine evaluation showed very low cortisol levels, low dehydroepiandrosterone-sulfate and elevated corticotropin, 11-deoxycortisol and delta-4-androstenedione. The concentration of 17-hydroxyprogesterone was 20,400ng/dL. After the cosyntropin stimulation test the pattern was similar and there was no significant increase in cortisol or 17-hydroxyprogesterone. The abdominal computed tomography scan revealed grossly enlarged and heterogeneous adrenal glands (left, 12cm; and right, six cm). A bilateral adrenalectomy was performed and pathologic examination revealed adrenal myelolipomas with nodular cortical hyperplasia. The sonogram showed bilateral heterogeneous masses on the upper pole of both testes which corresponded to the nodular hyperplasia of adrenal rest tissues. The genetic study revealed compound heterozigoty (mutations R124H and R356W), suggestive of a phenotypically moderate disease. We performed a cosyntropin stimulation test after adrenalectomy. The steroidogenic profile displayed the same unusual features, indicating an important contribution from the adrenogenital cells.ConclusionThis case illustrates that congenital adrenal hyperplasia due to 21-hydroxylase deficiency can progress to severe acute and chronic complications. The masses in the patient’s adrenal glands and testicles resulted from chronically elevated adrenocorticotropic hormone and growth of adrenocortical cells. The basal and stimulated steroid profile, before and after adrenalectomy, revealed an unexpected pattern, suggesting significant contribution of the testicular adrenal cells to the steroidogenesis.