Gardner's syndrome associated fibromas

Nuchal-type Fibroma: Single-Center Experience and Systematic Literature Review

BACKGROUND

Nuchal-type fibroma is a rare benign tumor arising from the connective tissue. Our aim was to present our experience via two cases of this tumor and a comprehensive review of the literature.

PATIENTS AND METHODS

We report a case of a 23-year-old female with a mass located in the posterior neck and the upper back and a case of a 50-year-old male with a mass located in the posterior neck, which were proved to be nuchal-type fibromas in the histopathological examination. We also searched the PubMed/Medline database for published cases of nuchal-type fibromas.

RESULTS AND DISCUSSION

Nuchal-type fibroma is a rare benign tumor arising from the connective tissue, usually in the posterior neck, which affects different ages, with most patients being male. It is a poorly circumscribed tumor consisting of hypocellular, thick, dense and haphazardly arranged collagen bundles with entrapped adipocytes, nerve fibers and muscle fascicles and a few scattered spindle cells, which are CD34 positive. Its excision is curative, and the recurrence risk is generally low. However, patients with Gardner's syndrome may experience recurrence more frequently.

CONCLUSION

Nuchal-type fibroma should be included in the differential diagnosis of subcutaneous, soft-tissue masses, especially when these involve the posterior neck.

From Gardner fibroma diagnosis to constitutional APC mutation detection: a one-way street

We report a young child without a family history of FAP, who promptly underwent APC testing after the histological confirmation of a paraspinal GAF that was not isolated. Our case report reinforces the suggestion advanced by previous authors for an APC analysis in all patients with GAF.

Gardner Fibroma: Clinical and Histopathologic Implications of Germline APC Mutation Association

The proportion and clinical characteristics of Gardner fibromas (GAFs) that are sporadic versus familial adenomatous polyposis (FAP)-associated have not been clearly established. We report on 7 patients diagnosed with GAF who underwent APC sequencing and duplication/deletion testing. Three (43%) were found to have underlying APC germline perturbations consistent with FAP; these patients had multifocal (1) or large; unresectable (2) GAFs. The 4 patients with negative APC testing each had a single resectable GAF. β-catenin reactivity was noted in all FAP-associated GAFs and in 1/4 APC wild-type cases. FAP-associated GAFs may be less common than sporadic GAFs and can demonstrate clinically distinct features.

Pediatric fibroblastic and myofibroblastic lesions

Fibrous lesions of infancy and childhood are a heterogeneous group of entities composed predominantly of fibroblasts and myofibroblasts, ranging from reactive lesions to neoplasms with a range of malignant potential. Although rare, their correct recognition by histopathology is important clinically as they exhibit a wide range of behaviors and may be associated with distinct underlying syndromes. Contributions from molecular diagnostics have enabled more accurate diagnosis, and have changed our concepts of some tumor types. In this review, we discuss the clinicopathologic spectrum of fibroblastic and myofibroblastic lesions of childhood and adolescence.

Extra nuchal-type fibroma associated with elastosis, traumatic neuroma, a rare APC gene missense mutation, and a very rare MUTYH gene polymorphism: a case report and review of the literature*

We report a case of an extra nuchal-type fibroma in a 51-year-old male suspected to have attenuated familial adenomatous polyposis (Gardner's syndrome), who presented with a longstanding buttock mass excised due to enlargement and pain. Histopathologically, lobules of haphazard, hypocellular, hyalinized collagen bundles replaced the dermis and subcutis and entrapped nerve bundles, mimicking Morton neuroma. Ramifying nerve twigs found around larger nerve fascicles showed the co-existence of traumatic neuroma. Elastic tissue stain revealed elastosis characterized by large, arborizing fibers lying between and within the hyalinized collagen bundles. Modified Masson's trichrome stain showed light blue staining of collagen bundles producing the hyalinized nodules with irregular, light red staining of collagen bundles at their periphery and within tumor collagen. Compression and/or degeneration of collagen and secondary elastosis with later entrapment by tumor collagen could explain this microscopic phenotype. By immunohistochemistry, tumor spindle cells expressed nuclear β-catenin and cyclin D1, mostly within regions of fibrosis implicating activation of the adenomatous polyposis coli (APC)-Wnt pathway. Genetic analysis showed a missense mutation in APC gene (c.7504G>A, p.G2502S in exon 15) and a functional homozygous polymorphism in the MUTYH gene (c.36+325G>C, (IVS1+5G/C)). Nuchal-type fibroma has been associated with Gardner's syndrome and trauma. In this patient, genetic predisposition coupled with repetitive, localized trauma and collagen degeneration may have provided the stimulus for the development of extra nuchal-type fibroma.

Neonatal Gardner fibroma: a sentinel presentation of severe familial adenomatous polyposis

Familial adenomatous polyposis (FAP) is a rare cause of colorectal cancer and rarely presents in early childhood. Various extracolonic manifestations, however, may be present before the development of overt polyposis. One of the rarest manifestations is the Gardner fibroma (GAF), which has particular histologic features. Here we report the case of a child who presented in the neonatal period with a paraspinal mass. Although the initial diagnosis was unclear, biopsy of a second lesion at 32 months of age, and a review of the first lesion, resulted in the diagnosis of GAF. After rectal bleeding at 47 months, colonoscopy revealed 75 to 100 colonic polyps. Adenomas were identified in multiple biopsies throughout the colon and from several polyps located in the duodenum. Polyps were visualized in the jejunum by wireless-capsule endoscopy. A total proctocolectomy was performed, and no malignant transformation was observed in the colon on pathologic inspection. A truncating mutation in APC (c.4479_4480delGG p.Glu1494LysfsX19) was identified in the child. Her parents and sister do not carry this mutation in lymphocyte DNA. To our knowledge, this is the first report of neonatal GAF as the presenting feature of a molecularly confirmed case of sporadic FAP and the earliest colonic and small bowel involvement reported of FAP. It illustrates the need to exclude FAP in a child who harbors fibromas suggestive of GAF, even in the absence of supportive evidence of FAP in the patient or relatives.

Nuchal-type fibroma of the ankle: a case report

Nuchal-type fibroma is rare benign fibrous tumor that has the potential to recur. It is typically located in the subcutaneous tissues of the posterior aspect of the neck, although it can affect other anatomical sites. Extranuchal involvement occurs most commonly in the back, shoulder, and face, as well as other sites specified in single case reports. In this report, we describe the case of a patient presenting with a nuchal-type fibroma arising in the ankle. The lesion infiltrated the superior extensor retinaculum. Marginal resection was performed, and there was no evidence of recurrence after 12 months of follow-up. To our knowledge, this is the first report of a nuchal-type fibroma localized to the ankle.

Gardner Fibroma: A Clinicopathologic and Immunohistochemical Analysis of 45 Patients With 57 Fibromas

Gardner fibroma (GAF) is a benign soft tissue lesion with a predilection for childhood and adolescence and an association with familial adenomatous polyposis (FAP) and desmoid type fibromatosis (desmoid). We report 45 patients with GAF with clinicopathologic correlation and immunohistochemical analysis for beta-catenin and related proteins. Forty-five patients with 57 GAFs were identified from surgical pathology and consultation files. Immunohistochemistry for beta-catenin, cyclin-D1, and C-myc was performed on formalin-fixed, paraffin-embedded tissues using standard techniques in 25 GAFs from 24 patients. Information about family history, intestinal polyps, colon cancer, and soft tissue tumors was available in 23 patients. Sixty-nine percent had known FAP or adenomatous polyposis coli (APC), 22% had no history of familial polyps or soft tissue tumors, and 13% had an individual or family history of soft tissue masses and/or desmoids, with follow-up periods of 6 months to 26 years (median 3 y, mean 5 y). The age range at initial diagnosis was 2 months to 36 years. Seventy-eight percent were diagnosed in the first decade, 15% in the second decade, and 7% in the third decade. Eight patients (18%) had documented desmoids concurrently or later; 4 of these had FAP and 1 had familial desmoids. Sites of GAF included the back and paraspinal region in 61%, the head and neck in 14%, the extremities in 14%, and the chest and abdomen in 11%. All displayed a bland hypocellular proliferation of haphazardly arranged coarse collagen fibers with a bland hypocellular proliferation of inconspicuous spindle cells, small blood vessels, and a sparse mast cell infiltrate. Immunohistochemically, 64% showed nuclear reactivity for beta-catenin (9 patients with known APC, 5 without definite information about FAP). One hundred percent showed nuclear reactivity for both cyclin-D1 and C-myc. beta-catenin reactivity had no correlation with age, site, or recurrence. Two beta-catenin-negative GAFs were from FAP patients. In conclusion, GAF has a predilection for childhood and early adulthood, a strong association with FAP/APC, an association with concurrent or subsequent development of desmoids, and overexpression of beta-catenin and other proteins in the APC and Wnt pathways. The proportion of sporadic GAFs that have APC mutation remains to be determined.