An evidence-based, multidisciplinary approach to the clinical considerations, management, and surveillance of adrenal lesions in familial adenomatous polyposis: report of three cases

Adrenal Lesions in Patients With (Attenuated) Familial Adenomatous Polyposis and MUTYH-Associated Polyposis

BACKGROUND

The reported proportion of patients with familial adenomatous polyposis who have adrenal lesions varies between 7% and 13% compared with 4% in the general population; the prevalence of adrenal lesions in patients with attenuated familial adenomatous polyposis and MUTYH-associated polyposis is unknown. Data on the clinical relevance and clinical course are limited.

OBJECTIVE

We aimed to report on the frequency, characteristics, and progression of adrenal lesions in polyposis patients.

DESIGN

This was a historical cohort study.

SETTINGS

The study was performed at the Academic Medical Center, Amsterdam.

PATIENTS

All of the patients with familial adenomatous polyposis, attenuated familial adenomatous polyposis, and MUTYH-associated polyposis were included. Medical charts and imaging reports were analyzed for data on adrenal lesions. A radiologist reassessed all of the images. Patients had not routinely been screened for adrenal lesions.

MAIN OUTCOME MEASURES

The frequency, characteristics, and progression of adrenal lesions in patients with polyposis who underwent abdominal imaging were assessed. Findings were compared with a reference.

RESULTS

A total of 39 adrenal lesions were identified in 23 (26%) of 90 patients with familial adenomatous polyposis, 2 (18%) of 11 with attenuated familial adenomatous polyposis, and 5 (24%) of 21 with MUTYH-associated polyposis. Mean age at time of detection was 50.7 years (range, 17.1-83.3 y). Median lesion size at baseline was 1.4 cm (range, 1.0-5.0 cm) versus 1.7 cm (range, 1.0-5.7 cm) after a median of 3.5 years (range, 1.0-11.4 y). Two patients were diagnosed with a hyperfunctioning lesion, and 4 underwent adrenalectomy: 3 lesions appeared benign, and 1 was oncocytic of uncertain malignant potential. The OR for detecting at least 1 lesion in a patient with polyposis versus reference was 6.2 (95% CI, 3.2-12.3), with no significant differences in ORs among the 3 syndromes.

LIMITATIONS

The study was limited by its retrospective design.

CONCLUSIONS

Adrenal lesions are frequent in patients with polyposis who undergo abdominal imaging. They appear to follow a benign and slowly progressive course and are mostly nonhyperfunctioning. See Abstract Video at http://links.lww.com/DCR/A323.

Rare and unusual endocrine cancer syndromes with mutated genes

The study of a number of rare familial syndromes associated with endocrine tumor development has led to the identification of genes involved in the development of these tumors. Major advances have expanded our understanding of the pathophysiology of these rare endocrine tumors, resulting in the elucidation of causative genes in rare familial diseases and a better understanding of the signaling pathways implicated in endocrine cancers. Recognition of the familial syndrome associated with a particular patient's endocrine tumor has important implications in terms of prognosis, screening of family members, and screening for associated conditions.

Quantitative evaluation of CpG island methylation in hyperplastic polyps

Microsatellite unstable cancers account for up to 15% of sporadic colon cancers and are predominantly located in the proximal colon. These cancers commonly show MLH1 promoter methylation and the CpG island methylator phenotype (CIMP). A potential precursor of sporadic unstable cancers, the proximal hyperplastic polyp, is also reported to have CIMP and MLH1 methylation. However, this latter finding is not supported by MLH1 protein expression studies. To help resolve this apparent discrepancy, we determined MLH1 promoter methylation and CIMP by quantitative real-time PCR for 29 proximal hyperplastic polyps, 23 distal hyperplastic polyps, and 11 sporadic microsatellite unstable colon cancers. BRAF V600E mutation status was also determined. Positive methylation was defined as the percentage of methylated reference (PMR) >10. Only 1 of 29 proximal hyperplastic polyps showed positive MLH1 methylation (PMR of 13.0). Neither this polyp nor seven other proximal polyps with PMR values between 0 and 10 showed loss of MLH1 protein expression by immunohistochemistry. In contrast, all 11 microsatellite unstable cancers showed high degrees of MLH1 methylation, with PMR values >30. Fourteen of twenty-nine (48%) of the proximal hyperplastic polyps and 1 of 23 (4%) of the distal hyperplastic polyps showed CIMP (P<0.001). Of the unstable cancers, 10 of 11 showed CIMP. The PMR values in the CIMP-positive proximal hyperplastic polyps were significantly lower than those of the unstable cancers for 4 of the 5 CIMP markers (P<0.05). BRAF V600E mutations were seen in 83% of proximal and 74% of distal hyperplastic polyps. Quantitative analysis of MLH1 methylation does not support earlier reports of MLH1 methylation in proximal hyperplastic polyps. However, these lesions do harbor promoter methylation at other CIMP loci, although at a lower level than that seen in unstable cancers. If these polyps are the precursor for sporadic microsatellite unstable cancers, then MLH1 methylation and higher degrees of promoter methylation in general occur at a later stage of carcinogenesis.

Adrenal incidentaloma in familial adenomatous polyposis: a long-term follow-up study and schema for management

PURPOSE

Adrenal incidentaloma is often diagnosed in patients with familial adenomatous polyposis, because they frequently undergo abdominal imaging and have a raised incidence of adrenal incidentaloma. This study investigates the natural history of adrenal incidentaloma in familial adenomatous polyposis, and suggests a schema for management.

METHODS

An original cohort of 14 familial adenomatous polyposis patients with adrenal incidentaloma, identified prospectively 12 years ago, was followed up clinically and radiologically. A further group of 16 patients was also identified. All had lesions >1 cm. For both cohorts, characteristics of patients (genotype, age at diagnosis, concomitant diagnoses) and incidentaloma (size, laterality, rate of growth, outcome) are described.

RESULTS

Overall, 3 of 30 patients underwent adrenalectomy; one patient had pheochromocytoma and another had an adenoma of borderline malignancy. A further three lesions were radiologically suspicious for malignancy at the time of diagnosis; one was in a patient who was unfit for surgery but died of nonadrenal causes after nine years. None of the lesions radiologically benign at diagnosis showed an aggressive course, but one patient required referral for surgery after 12 years because of a slow increase in size of the lesion. There were no associations with genotype.

CONCLUSIONS

Familial adenomatous polyposis-associated adrenal incidentaloma may warrant long-term follow-up. Although the natural history is similar to lesions occurring sporadically, these patients have concomitant familial adenomatous polyposis-associated manifestations under radiologic surveillance. In this rare condition, development of a robust protocol will require evidence from worldwide patient cohorts. However, a tailored schema is suggested as a consistent basis for future modification.

Biallelic APC inactivation was responsible for functional adrenocortical adenoma in familial adenomatous polyposis with novel germline mutation of the APC gene: report of a case

Familial adenomatous polyposis (FAP) patients develop various extracolonic lesions, among which functional adrenocortical neoplasms are infrequent. A 44-year-old woman was hospitalized because of pseudo-Meigs' syndrome, caused by bilateral ovarian metastases from an advanced ascending colon cancer due to FAP of intermediate type. Furthermore, bilateral adrenocortical adenomas were detected, and functional analyses showed a hormonal secretion pattern consistent with Cushing's syndrome. She underwent a right hemicolectomy with extirpation of bilateral ovaries. At 10 months post-operative with no detectable metastatic lesions, the residual colorectum and the larger, left adrenal gland were resected, and the hormonal hypersecretion was normalized. Direct sequencing of the adenomatous polyposis coli (APC) gene revealed a nonsense germline mutation at codon 1577 and an additional nonsense somatic mutation at codon 554 in cancer tissues. Biallelic APC inactivation due to loss of the normal allele was evident in the adrenocortical adenoma. There were no hypermethylated CpG islands detected in APC promoter regions. Immunostaining for beta-catenin revealed diffuse cytoplasmic expression in resected tissues including adrenocortical adenoma. Biallelic APC inactivation may play a role in developing cortisol-secreting adrenocortical adenoma in FAP patients. It is noteworthy that biallelic APC inactivation was caused in different ways in different tumors from the same individual.