Adrenal Cortical Carcinoma and Additional Rare Pathologic Findings in Multi-Organs in a Birt-Hogg-Dubé Syndrome Patient: With an Emphasis on the Molecular Characteristics of Adrenal Cortical Carcinoma
International Journal of Surgical Pathology 2023, Vol. 31(5) 689-694 @ The Author(s) 2022 Article reuse guidelines: sagepub.com/journals-permissions DOI: 10.1177/10668969221117246
S Sage
David Kim, MD’, Natia Murvelashvili, MD2, Oksana Hamidi, MD2, and Liwei Jia, MD, PhD’ iD
Abstract
Birt-Hogg-Dubé (BHD) syndrome is a rare autosomal dominant disorder caused by germline alterations in the FLCN gene. We report a 38-year-old man with BHD syndrome presenting with multiple rare pathologic findings involving various organs, including adrenal cortical carcinoma (ACC). Initially, he presented with severe cholestatic jaundice and was found to have a 25 cm left adrenal mass with radiologic evidence of lung metastases, which was diagnosed as ACC on resection. Concurrently, pigmented, bile-stained granular casts were present within the kidney and diffuse cholestasis of the liver con- sistent with Stauffer syndrome was identified. Subsequent staging workup detected a 1.2 cm tubulovillous adenoma in the dis- tal ascending colon and an incidental 1.2 cm thyroid nodule. Germline genetic testing revealed a pathogenic FLCN c. 1285dup. Targeted DNA next generation sequencing of ACC revealed FLCN c.1285dup, IDH2 c.5332C>T, PRKAR1A c.1074del, and PDGFRB c.3282C>A and concurrent transcriptomic analysis demonstrated VEGFA overexpression. Fourteen months after resection, follow-up computerized tomography (CT) identified the progression of lung metastases and chemotherapy with etoposide doxorubicin and cisplatin was initiated. Here, we report the first ACC with the molecular characteristics in a BHD syndrome patient, although 5 adrenal lesions, including ACC, adenomas or neoplasm with malignant potential due to higher Ki67 labelling index, have been reported in the literature and no somatic analysis in these tumors were performed. Despite the rarity, our case potentially expands the tumor spectrum of BHD patients, helps to solidify possible association with adrenal cortical tumors and reiterates the value of genetic counseling in patients with ACC.
Keywords
adrenal cortical carcinoma, Birt-Hogg-Dubé syndrome, FLCN gene, tubulovillous adenoma, thyroid nodule
Introduction
Birt-Hogg-Dubé (BHD) syndrome is a rare autosomal domi- nant genodermatosis caused by germline alterations in the FLCN gene and predisposes patients to develop multiple fibro- folliculomas, pulmonary cysts, often leading to spontaneous pneumothoraxes, and varying histotypes of renal neoplasms. The FLCN gene encodes a tumor suppressor protein, folliculin (FLCN), mapped to chromosome 17p11.2.1 Although the function of the FLCN protein is largely unknown, it has been linked to the mTOR pathway and is expressed in a wide variety of tissues, including skin, type-1 pneumocytes of the lungs, and the distal nephron of the kidneys.2 In addi- tion, reduced expression of the FLCN gene has been seen in renal tumors of patients with BHD syndrome.
Adrenal cortical carcinoma (ACC) is a rare and aggres- sive endocrine malignancy, with an incidence of 0.5-2/
million per year,3,4 and a 5-year survival rate of 16-44%.4 Most ACCs occur sporadically,3 but it is rarely associated with multiple familial syndromes, including Li-Fraumeni syndrome, Beckwith-Wiedemann syndrome, multiple endocrine neoplasia 1, familial adenomatous pol- yposis, and Carney complex.5 A literature search yielded 5 adrenal cortical lesions seen in BHD syndrome patients, including ACC, adenomas and neoplasm with malignant
‘Department of Pathology, UT Southwestern Medical Center, Dallas, TX, USA
2Division of Endocrinology and Metabolism, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, TX, USA
Corresponding Author:
Liwei Jia, Department of Pathology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX, 75390, USA. Email: Liwei.Jia@UTSouthwestern.edu
potentially due to a higher Ki67 labelling index.6 To the best of our knowledge, we report a case of ACC occurring in a patient with BHD syndrome with emphasis on its molecular alterations. Despite the rarity, our case poten- tially expands the tumor spectrum of BHD syndrome patients and helps to solidify possible association with adrenal cortical tumors. It also reiterates the value of genetic counseling in patients with ACC.
In addition to ACC, other uncommon pathologic find- ings involving various organs were also seen in this patient, including a 1.2 cm tubulovillous adenoma in the distal ascending colon, an incidental 1.2 cm thyroid nodule, and diffuse cholestasis of the liver consistent with Stauffer syndrome, a paraneoplastic syndrome characterized by reversible cholestasis in the absence of direct hepatobiliary obstruction, jaundice, or metasta- ses. The patient was also found to have pigmented, bile-stained granular casts in the ipsilateral kidney, likely related to hyperbilirubinemia in the setting of Stauffer syndrome.
Case Report
A previously healthy 38-year-old man initially presented with severe cholestatic jaundice and was found to have a large, well-demarcated adrenal mass on computerized tomography (CT) scan during diagnostic workup. Three months later, he developed altered mental status and disori- entation. Physical exam revealed dry mucus membranes, scleral icterus, and jaundiced skin. Laboratory testing dem- onstrated elevated ammonia, anemia, coagulopathy, ele- vated dehydroepiandrosterone sulfate (DHEA-S) at 1764.2 ug/dL (reference range: 57-522 mcg/dL), and ele- vated 11-deoxycortisol at 750 ng/dL (reference range: 10- 79 ng/dL). Magnetic resonance imaging (MRI) of the abdomen showed a large 25 cm heterogeneous mass in the expected region of the left adrenal gland that abutted and displaced the left kidney inferiorly, and the pancreatic tail anteriorly. Hepatosplenomegaly was also noted with enlargement of the splenic vein, portal vein, and portosplenic confluence. No liver masses or tumor thrombi were identified on the imaging studies. Additional series of chest CT detected bilateral sub- centimeter pulmonary nodules, which were increasing in size, and a few scattered cysts with very thin, barely perceptible walls in the lung fields that were stable. Core needle liver biopsy showed a predominant pattern of cholestatic liver injury.
En bloc left adrenalectomy with resection of the mass and left kidney showed a 25 cm well-circumscribed mass significantly displacing the left adrenal gland and encasing the left kidney without invasion into the renal parenchyma. The cut surface of the tumor was pale to golden yellow with central hemorrhage (Figure 1A). There were no gross lesions within the kidney. Microscopic examination
of the mass demonstrated an encapsulated tumor composed of sheets of tumor cells with less than 25% of tumor volume showing clear cytoplasm (Figure 1B), brisk mitotic activities (16 mitoses per 50 high power fields from hot spots), and fre- quent atypical mitoses (Figure 1C). Geographic necrosis (Figure 1D) was evident throughout the tumor, and capsular invasion into perinephric adipose tissue (Figure 1E) was also prominent. A modified Wiess score of 7 was given. Further immunohistochemical workup revealed the positivity for ster- oidogenic factor 1 (SF-1) and inhibin and lack of reactivity for AE1/AE3. Ki67 proliferation index of the tumor was 30% by manually counting 500 tumor cells from hot spots on the print- out images. The morphologic and immunophenotypic findings supported a diagnosis of ACC.
Representative sections of the kidney showed mild acute tubular injury and pigmented granular casts (Figure 1F). The casts were negative for iron special stain, which best represented bile-stained granular casts. At this time, a liver wedge resection was also attempted to assess the progression of his cholestatic disease. Microscopic examination showed diffuse cholestasis of the liver (Figure 1G), which was clinically consistent with Stauffer syndrome, a paraneoplastic syndrome char- acterized by reversible cholestasis in the absence of direct hepatobiliary obstruction or metastases.
His liver enzymes improved during the post-operative course and repeat DHEA-S and 11-deoxycortisol decreased to 39 ug/dL and 11 ng/dL, respectively. Ten months after surgery, he presented with hematochezia, and his colonoscopy revealed a 1.2 cm sessile polyp in the distal ascending colon. Subsequent polypectomy was per- formed and showed a tubulovillous adenoma (Figure 1H). A 1.2 cm thyroid nodule was incidentally discovered, with almost completely solid hypoechoic component, smooth margins and no suspicious echogenic foci detected. Based on imaging characteristics, it was classified as American College of Radiology Thyroid Imaging Reporting and Data System (ACR TI-RADS) 4 and the patient was recommended to undergo a follow-up ultrasound in 1 year.
Given the patient’s age, clinical findings of facial fibro- folliculomas, radiologic evidence of pulmonary cysts, and the diagnosis of ACC, germline genetic testing was recom- mended, which revealed a pathogenic FLCN c.1285dup in exon 11 (p.His429Profs*27). Taken together, this was con- sistent with BHD syndrome. Subsequent targeted DNA next generation sequencing using Tempus xT assay consisting of 648 genes revealed FLCN c.1285dup, IDH2 c.5332C>T, PRKAR1A c.1074del, PDGFRB c.3282C>A and concurrent transcriptomic analysis demonstrated VEGFA overexpres- sion. No alterations of TP53, CTNNB1, MLH1, MSH2, MSH6 or PMS2 genes were detected. Microsatellite instabil- ity status was stable. The patient was treated with mitotane for ACC. However, the treatment was discontinued due to the elevation of his liver enzymes. Fourteen months after resec- tion, follow-up CT scan of the chest, abdomen and pelvis
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revealed interval increase in size of innumerable pulmonary nodules with the largest being 2.2 cm, consistent with pro- gression of metastatic disease. There was no adenopathy or
evidence of recurrence or metastatic disease in the abdomen or pelvis. Therefore, chemotherapy with etoposide doxorubi- cin and cisplatin was initiated.
Discussion
Birt-Hogg-Dubé (BHD) syndrome is a rare autosomal dominant syndrome caused by germline mutations of the FLCN gene1 and characterized by a constellation of cuta- neous fibrofolliculomas, pulmonary cysts and renal cell tumors.7 A study of 10 French families affected by BHD syndrome8 demonstrated five or more facial fibrofolliculo- mas in 18 of 22 individuals (82%), pulmonary cystic lesions detected in 14 of 20 patients (70%), mainly in a subpleural and basal location, spontaneous pneumothora- ces reported in seven affected patients (32%), benign renal cysts in 10 patients (45%), and thyroid nodules and/or cysts without underlying malignancy disclosed by ultrasound examination in 13 of 20 cases (65%). Patients affected with BHD syndrome have an increased risk for developing several different histotypes of renal cell neo- plasms, including clear cell, papillary, or chromophobe renal cell carcinoma, renal oncocytoma, and hybrid onco- cytic/chromophobe tumors. Hybrid oncocytic/chromophobe renal tumors are the most common renal neoplasms found in BHD syndrome patients. A wide spectrum of neoplastic and non-neoplastic processes has been described in BHD syn- drome patients. Other neoplasms reported in BHD syndrome patients include melanoma,9 leiomyosarcoma,10 vestibular schwannoma,11 and even lymphoplasmacytic lymphoma.12 Here, we described rare pathologic findings involving multi- ple organs in a 38-year-old man with BHD syndrome, includ- ing ACC, tubulovillous adenoma in the distal ascending colon, an incidental thyroid nodule, diffuse cholestasis of the liver consistent with Stauffer syndrome, and pigmented, bile-stained granular casts in the kidney.
ACC is a rare endocrine malignancy and is most associ- ated with Li-Fraumeni syndrome, although most cases are sporadic. A retrospective review of the literature yielded five cases of adrenal tumors in BHD patients. A 4 cm ACC was reported in a 30-year-old woman and genetic screening demonstrated a heterozygous 2-base-pair dele- tion in exon 9 (c.941_942del; pP314fs) of FLCN gene.13 However, no somatic analysis was done in her ACC. No metastasis or recurrence was observed three years after resection. Raymond et al reported a 62-year-old female with a 6.2 cm right adrenal mass, diagnosed as an oncocytic adrenal cortical neoplasm with uncertain malignant potential on resection.6 They then searched the University of Michigan Cancer Genetics Registry for patients with confirmed FLCN mutations. Of the fourteen patients, one patient was found to have an adrenal lesion, which was stable at 1.2 cm, but no tissue diagnosis was made. A retrospective review of 359 patients diagnosed with ACC in the Michigan Endocrine Oncology Repository found no patients who fulfilled clinical criteria for BHD, had undergone germline genetic testing for FLCN mutations or had a reported family history of BHD. They concluded that adrenal tumors may be more common in BHD syndrome patients, although no cases of ACC
were present in their cohort. Conversely, they concluded that BHD may not be common among ACC patients. Kunogi et al looked at the clinical and genetic spectrum of BHD syndrome in 30 patients, of which only one patient pre- sented with a non-functioning adrenal adenoma.14 Juszczak et al reported a case of a 36-year-old female who had an inci- dental 11 cm left adrenal cortical tumor without malignant features on microscopic examination.15 A 3.7 cm oncocy- toma of the adrenal gland was reported in a 32-year-old BHD syndrome man with c.1285 dupC confirmed by genetic test.16 Our case is an ACC occurring in a BHD syn- drome patient with suspicious radiologic evidence of bilateral pulmonary metastases, which harbored IDH2 c.5332C>T, PRKAR1A c.1074del, PDGFRB c.3282C>A, in addition to FLCN c.1285dup and had VEGFA overexpression by tran- scriptomic analysis. A comprehensive genomic characteriza- tion of ACC lead by The Cancer Genome Atlas (TCGA) using a dataset of 91 ACCs expanded ACC driver genes including TP53, ZNFR3, CTNNB1, PRKARIA, CCNEI, and TERF2.17 Two patients in this cohort were detected to harbor FLCN alterations: one 65-year-old man with FLCN deep deletion, in addition to CTNNB1 p.S45F and TP53 p.C275S, who had no available clinical information regarding BHD syndrome and deceased 16 month later, and one 67-year-old woman with FLCN p.S62R missense mutation of unknown biologic significance, in addition to CTNNB1 p.S45P, who was cancer free after 152 months. IDH2 alter- ations were not detected in any of the ACCs in the study (https://www.cbioportal.org/).
Additionally, the patient underwent a colonoscopy sec- ondary to a complaint of hematochezia, which found a 1.2 cm sessile polyp in the distal ascending. A subsequent biopsy revealed a tubulovillous adenoma. Colorectal ade- nomas and carcinomas have been reported in BHD patients.9 However, the association between colorectal adenomas and carcinomas with BHD patients remains con- troversial. Colorectal polyps were identified in 9 of 18 (50%) of BHD syndrome patients analyzed in Kluger et al’s study of 10 French families with BHD syndrome.8 In the study, one of nine (11%) was found to have a tubu- lovillous adenoma with high-grade dysplasia, and one of nine (11%) was found to have a benign gastric polyp. No gastric or colorectal carcinoma was diagnosed in the study. Similarly, van de Beek et al found no evidence of increased prevalence of colorectal carcinoma in BHD patients.18 In contrast, Sattler et al stated that the rate of colorectal carcinoma was moderately but significantly increased and argued for preventative screening.19 A higher incidence of colorectal polyps and carcinomas in patients with confirmed FLCN germline mutations was observed by Khoo et al.20 Their further evaluations of the role of the FLCN gene in 47 unselected colorectal tumors (10 polyps and 37 carcinomas) suggested its involvement in the tumorigenesis in a subset of microsatel- lite stable (MSS) sporadic colorectal carcinomas and that
allelic loss in the region close to the BHD gene may play a role in colorectal tumor progression.21 Nahorski et al did not find any FLCN germline mutations among 50 patients with familial non-syndromic colorectal cancer.22 In the same study involving 51 families with BHD syndrome, the authors found that those with the 1285dupC mutation (within the exon 11 C8 mononucleotide tract) had a higher risk of colo- rectal neoplasia compared to those with the 610delGCinsTA mutation (P =. 016). Furthermore, somatic frameshift muta- tions in the exon 11 C8 mononucleotide tract of FLCN were detected in 7 of 30 (23%) sporadic colorectal cancers with microsatellite instability. The frequency of these somatic mutations was more common in tumors that also showed loss of MLH1 or MSH2 protein expression. The find- ings suggested that FLCN inactivation may contribute to colorectal tumorigenesis. Nevertheless, a diagnosis of a tubu- lovillous adenoma in our patient at a young age warrants colonoscopy screening every 3 years.23
A spectrum of FLCN mutations has been described in BHD syndrome. A total of 23 different mutations in the FLCN gene was identified by Toro et al from 51 of 58 (88%) BHD syndrome families, with 1285insC and 1285delC mutations being most common.24 There were no apparent genotype/phenotype correlations. Germline insertion or deletion of a cytosine in the hypermutable pol- ycytosine tract in exon 11 of the FLCN gene has been detected in 53% of BHD syndrome families,25 and is, therefore, suggested as a mutation “hot spot.” Most FLCN germline mutations are frameshift, or nonsense mutations predicted to truncate FLCN protein. FLCN c.1285dup in exon 11 (p.His429Profs*27) found in our patient is a pathogenic germline alteration, which causes a frameshift variant.26 Using small interfering RNAs with several human cell lines, Hartman et al found down- regulation of BHD reduced phosphorylation of ribosomal protein S6 (RPS6), a key mediator of mTOR function,27 suggesting that BHD upregulates the activity of the TORC1 complex.28 Using mouse xenograft assays of two human renal cell carcinoma cell lines, Hudon et al con- firmed the tumor suppressor activity of FLCN in the kidney and that loss of FLCN expression resulted in improperly elevated or diminished activation of RPS6, depending on cellular context.29 Heterozygous loss of FLCN in mice caused kidney tumor development with activation of TORC1 and TORC2.30 Human BHD-associated kidney tumors showed similar activation of TORC1 and TORC2.31 There is no reported study on the pathogenesis of FLCN in adrenal cortical tumors.
ACC is a rare malignant endocrine tumor, and our case demonstrated the molecular characteristics of ACC occur- ring in a patient with BHD syndrome in addition to other rare pathologic findings, including a tubulovillous adenoma and a thyroid nodule. Despite the rarity, our case potentially expands the tumor spectrum of BHD syn- drome patients, solidifies possible association with adrenal
cortical tumors, and reiterates the value of genetic counsel- ing in patients with ACC. The additional histologic find- ings found in his kidney and liver also add to the uniqueness of this case.
Declaration of Conflicting Interests
The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding
The author(s) received no financial support for the research, authorship, and/or publication of this article.
Ethical Approval
Not applicable, because this article does not contain any studies with human or animal subjects.
Informed Consent
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ORCID iD
Liwei Jia ID https://orcid.org/0000-0002-2118-6428
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