Folliculo-sebaceous cystic hamartoma

Giant Folliculosebaceous Cystic Hamartoma of the Face

Folliculosebaceous cystic hamartoma (FSCH) is a rare and benign form of cutaneous hamartomas. These skin lesions often lead to clinical and histopathological misdiagnosis due to their similarities to cutaneous lesions with overproduction of clustered sebaceous glands. Clinically, the lesions often present as solitary, skin-colored, pedunculated warts to cauliflower-like, exophytic papules and nodules, usually with a diameter ranging 0.5-1.5 cm that rarely exceed 2 cm in size. Only a small number of giant variants are reported in the literature with a diameter in the range of 5-23 cm. The vast majority of the lesions appear in the central face and show a striking predilection for the nose, ears, and scalp, but also emerge on the nipples, extremities, and genitals. Histologically, the epithelial components of folliculosebaceous cystic hamartoma comprise dilated infundibular cystic proliferation with surrounding mesenchymal components, which commonly include fibroplasia and vascular and adipose tissue proliferation. These histological characteristics were coined by Kimura and colleagues (1991). To the best of our knowledge, our case represents the biggest variant of giant folliculosebaceous cystic hamartoma.

Folliculosebaceous Cystic Hamartoma Mimicking Preauricular Sinus Cyst

Folliculosebaceous cystic hamartoma (FSCH) is a rare cutaneous hamartoma that consists of follicular, sebaceous, and mesenchymal elements. These lesions are mostly seen on the central face and scalp of adults and mostly present as single 0.5-1.5 cm papules or exophytic nodules. A 17-year-old female patient presented at our clinic with the complaint of swelling, pain and discharge in front of the left ear, which had been recurrent since childhood. The lesion was clinically suspected to be an infected preauriculer sinus cyst. After the medical treatment, the patient was operated on with a pre-diagnosis of preauricular sinus cyst. Histopathological findings revealed FSCH. To the best of our knowledge, this is the first reported case of FSCH originating from the preauricular region, located subcutaneously.

Hamartomas of skin and soft tissue

Hamartomas are benign lesions composed of aberrant disorganized growth of mature tissues. Choristomas are similar, except that they are composed of tissues not normally found at the anatomic site in which the lesion is arising. A wide range of hamartomas and choristomas can arise in the skin and soft tissue. Some of these may cause diagnostic difficulty and potentially be mistaken for neoplasms. Some neoplasms may resemble hamaratomas. Here we review the current clinical and pathologic features of these lesions, both common and rare, and discuss how to distinguish them from other entities in the differential diagnosis.

Collision Tumor between Trichofolliculoma and Melanocytic Nevus

Trichofolliculoma (TF) is a hamartomatous hair follicle-related tumor, clinically described as a dome-shaped papule with a central pore crossed by one or more silky white hairs. Histologically, it described as a cystic cavity containing keratinous debris, hair shaft fragments, and numerous hair follicles arising from its linings. Collision or compound tumors are a coexistence of two or more identifiable tumors in the same lesion. We present a case of a 47-year-old man with a lesion on his left cheek clinically characterized as a TF. However, the histopathological study reveals a collision tumor involving a TF and a melanocytic nevus. Collision tumors involving melanocytic nevi and hair follicle-related tumors have been previously reported, such as desmoplastic trichoepithelioma, epidermoid cyst, folliculosebaceous cystic hamartoma, and trichoadenoma.

Chronological changes in trichofolliculoma: Folliculosebaceous cystic hamartoma is not a very-late-stage trichofolliculoma

Some authors have reported that the secondary hair follicles in trichofolliculomas (TF) undergo regressive changes and are subsequently replaced by the developed sebaceous elements, and that folliculosebaceous cystic hamartoma (FSCH) is a TF at a very late stage. In the present study, we revaluated the histopathological features of 40 TF lesions, focusing on their chronological changes. The results of the present study indicate that while the secondary follicles in the TF exhibited the hair cycle, the normal hair cycle was out of control, and tertiary hair follicles randomly developed from the involuting secondary follicles. The repeated development of hair follicles in this disordered hair cycle caused the development of chains of several continuous hair follicles in late-stage TF. In the TF lesions, no features indicating the replacement of the regressing secondary hair follicles by any sebaceous elements were observed, thereby suggesting that FSCH is not a very-late-stage TF.

Genital folliculo-sebaceous cystic hamartoma: A claim of the stroma as a clue in the diagnosis of proliferations with follicular differentiation

Folliculo-sebaceous hamartomas comprise a series of entities whose boundaries are imprecise. We present the clinical case of a folliculo-sebaceous cystic hamartoma of genital localization where the diagnosis was established based on the epithelial proliferation, but mostly, on the characteristic stroma. Because this lesion lacked of the cystic component, we mention the most frequent differential diagnoses and review the literature of the few cases published on this infrequent localization.

Folliculosebaceous cystic hamartoma of the ear and periauricular skin

Folliculosebaceous cystic hamartoma (FSCH) is a rare, recently recognized cutaneous hamartoma comprised of follicular, sebaceous and mesenchymal elements. Fewer than 30 cases have been reported to date. The authors present two additional cases of FSCH.

Folliculosebaceous cystic hamartoma in a patient with neurofibromatosis type I

Folliculosebaceous cystic hamartoma (FSCH) is a rare cutaneous hamartoma composed of dilated folliculosebaceous units and mesenchymal elements. It presents as a papule or nodule usually on the face and scalp, rarely on the genital or trunk area. Histologically, FSCH shares several similar features to sebaceous trichofolliculoma. We report one case of FSCH misdiagnosed as a neurofibroma. He was a 38-year-old man with a neurofibromatosis type I and a nodule on his left earlobe was excised under the impression of neurofibroma. Pathological examination revealed FSCH. Although FSCH is clinically not distinctive, awareness of the lesion is important to differentiate papulonodular or cyst-like cutaneous lesions.

A case of giant folliculosebaceous cystic hamartoma

Clinically, folliculosebaceous cystic hamartoma (FSCH) lacks distinct features, but it has been reported as an asymptomatic, 1- to 3-cm, dome-shaped nodule on the face. Histopathologically, FSCH is characterized by adnexal and folliculosebaceous cystic proliferation with various mesenchymal changes. This case presented an unusually large, small-fist-sized mass in the right mandibular area that was accompanied by intermittent itching. Histopathologic findings demonstrated appropriate features of FSCH. We present an interesting case of giant FSCH in a 48-year-old female.

Clinicopathological and immnuohistochemical findings in a series of folliculosebaceous cystic hamartoma

BACKGROUND

Folliculo-sebaceous cystic hamartoma (FSCH) is an uncommon skin condition presenting as a slow-growing papulo-nodular lesion, in or around the nose. Most cases are not clinically suspected and only histopathological examination allows the diagnosis. Pathological features include a dermal-located infundibulo-cystic structure with sebaceous glands radiating around, a stromal component encircling the epithelial structures, with clefts between the lesional epithelial and stromal parts, as well as between this and the adjacent dermis.

RESULTS

We report eight patients with the diagnosis of FSCH (5 females and 3 males), with ages ranging from 35 to 77 years. Most cases (5 out of 8) were located in or around the nose and sizes were comprised between 0.6 and 1.2 cm. Lesions had grown for long periods of time, up to ten years in one case. Immunohistochemistry showed staining for p63 in the epithelial component of all lesions, while CD10 was only present in some sebocytes. CD34 and Factor XIIIa positive cells were present in the lesional stroma. Staining for androgen and alpha-estrogen receptors was also usually noticed.

CONCLUSIONS

FCSH is a hamartomatous skin lesion, clinically indistinct but with well-defined histopathological features. Immunohistochemistry shows a profile very close to normal sebaceous glands.

Two cases of folliculosebaceous cystic hamartoma

Folliculosebaceous cystic hamartoma (FSCH) is a rare cutaneous hamartoma composed of dilated folliculosebaceous units associated with mesenchymal elements. Two cases of FSCH with typical histopathological features are reported. Patient 1 was a 60-year-old man presented with a normal skin-coloured asymptomatic nodule on his scalp. Patient 2 was a 70-year-old man with an asymptomatic nodule on his right auricle that had persisted for the previous 15 years. In all, 34 cases of FSCH have been reported in the English literature. Clinically, the lesions are asymptomatic, usually rubbery to firm in consistency, and usually occur on or above the neck (> 90%). Most lesions do not exceed 25 mm in diameter (> 90%). Histopathologically, FSCH shares several similar features to sebaceous trichofolliculoma, but it is usually possible to differentiate these two tumours.

A case of genital folliculosebaceous cystic hamartoma with an unique aggregated manifestation

Folliculosebaceous cystic hamartoma (FCH) is a recently recognized cutaneous hamartoma composed of follicular, sebaceous and mesenchymal components, and usually occurring on the head and neck. We describe herein a case of FCH with an unique aggregated manifestation in a genital lesion. The patient was a 40-year-old woman with a genital lesion composed of a pedunculated nodule, a dome-shaped nodule and a subcutaneous nodule, measuring 5 cm in the greatest dimension. The largest, pedunculated nodule was histologically composed of an infundibulo-cystic structure with follicular, sebaceous and mesenchymal elements accompanied by cystic structures of various sizes lined by stratified squamous epithelium and follicular germinative cells suggesting follicular cysts. The dome-shaped nodule consisted of anastomosing strands of epithelial cells with follicular components. The subcutaneous nodule had two components, an infundibulo-cystic structure and a cyst lined by squamous epithelium. In our case, the unusual clinical feature of large and multiple nodules was due to the presence of several prominent hamartomatous cystic structures with FCH. This is the third case of giant FCH. The clinical presentation and location of giant FCH is unusual.

[Facial folliculo-sebaceous cystic hamartoma. Treatment with CO2 and Er:YAG lasers]

Folliculo-sebaceous cystic hamartoma (FCH) is defined as an adnexal hamartoma. The histopathological findings of FCH are equivalent to a very late stage of trichofolliculoma. The clinical appearance of FCH is unspecific. For this reason in the majority of cases it is only the histopathological examination that leads to the diagnosis of FCH. Up to now FCH has been treated with surgical procedures. We combined the use of both CO2 and Er:YAG lasers to treat a facial FCH.