A Case of Trichoblastoma, Tumor of the Follicular Infundibulum, Sebaceoma, and Sebaceous Hyperplasia Arising from Nevus Sebaceus / 대한피부과학회지

Nevus sebaceus is a congenital hamartoma with epidermal, follicular, and apocrine elements. Several skin appendage tumors can evolve secondarily from nevus sebaceus. Two different tumors often develop simultaneously on a nevus sebaceus lesion, but the growth of more than two tumors is rare. Herein, we report a case of four appendage tumors including trichoblastoma, tumor of the follicular infundibulum, sebaceoma, and sebaceous hyperplasia within a single nevus sebaceus lesion on the face of a 76-year-old female.

A Case of Cowden Syndrome Associated with Tumor of the Follicular Infundibulum / 대한피부과학회지

Cowden Syndrome (CS) is a rare genodermatosis of autosomal-dominant inheritance, with variable expressivity and multiple types of hamartomas. The most consistent features of CS are small wart-like papillomatous papules on the face, hands, and mouth. A 31-year-old woman presented with a history of pearly papules on the face, hand, and foot for several years. The lesions were initially diagnosed as warts, and treated accordingly, but they did not subside. There was a history of endometrial cancer, breast cancer, and thyroid nodule, and her father had a history of thyroid cancer. A biopsy specimen from the facial papule showed plate-like growth of anastomosing epithelial cords, extending parallel to the epidermis. It was diagnosed as a tumor of the follicular infundibulum (TFI). The patient refused further treatment. Here, we report a rare case of CS presenting with TFI.

Tumor of follicular infundibulum: An unsuspected cause of macular hypopigmentation.

We present three cases of a rare eruptive variant of tumor of follicular infundibulum. Two patients presented with hypopigmented macules. The clinical differential diagnoses considered in these two cases were vitiligo, lichen sclerosus et atrophicus, and idiopathic guttate hypomelanosis. In the third case, the lesions were hypopigmented fl at topped maculo-papules diagnosed clinically as verruca plana. In all three cases, the histopathological features of plate like growth of pale keratinocytes connected to the epidermis and peritumoral condensation of elastic fi bers were diagnostic. Although no satisfactory treatment is available, the exclusion of other clinical differential diagnosis particularly vitiligo with its psychosocial implications underscores the importance of skin biopsy.

A Case of Tumor of the Follicular Infundibulum with Sebaceous Differentiation

Tumor of the follicular infundibulum (TFI) is an uncommon benign adnexal tumor that usually presents as a solitary keratotic papule on the face or scalp of elderly patients. Histopathologically, it typically manifests as a plate-like fenestrated proliferation of monomorphic pale-staining cells. A 76-year-old male presented with about a 2 cm, well-defined, yellowish to brownish, slightly elevated, twisted and bent, interrupted, cord-like plaque on his left lower abdomen. Microscopic examination revealed a sharply demarcated plate-like proliferation of pale cells localized in the papillary dermis with multiple connections to the overlying epidermis. The histopathological features were compatible with TFI, except for foci of sebaceous differentiation. There has been one previous case report of TFI with sebaceous differentiation in the English medical literature. Herein, we report on a singular case of TFI with sebaceous differentiation.

Queratosis folicular invertida pigmentada: a propósito de un caso: [revisión] / Inverted follicular keratosis: a case report: [review]

La queratosis folicular invertida (QFI) es una lesión benigna del infundíbulo folicular. Es poco frecuente y habitualmente el diagnostico es histopatológico. Clínicamente no presenta características propias ni patognomónicas, por lo que generalmente semeja otras lesiones proliferativas de la piel, como las verrugas, el carcinoma basocelular, las queratosis seborreicas y otros tumores benignos. La forma pigmentada es infrecuente y suele confundirse con melanoma. La queratosis folicular invertida es una entidad de histogénesis controvertida, proponiéndose como alternativas que sea una neoplasia benigna con diferenciación folicular, una variante de verruga vulgar o una queratosis seborreica irritada. El tratamiento de la queratosis folicular invertida es la extirpación completa de la lesión, con un excelente pronóstico, casi sin recurrencias.

Inverted follicular keratosis (IFK) is a benign lesion of follicular infundibulum. It is rare, and diagnosis is usually histopathological. Clinically, it is unique, with no pathognomonic characteristics and therefore often resembles other skin proliferative lesions such as warts, basal cell carcinoma, seborrheic keratoses and other benign tumors. The pigmented form is rare and often confused with melanoma. Inverted follicular keratosis is an entity of controversial histogenesis, alternatively considered as a benign neoplasm with follicular differentiation, a variant of vulgaris warts or irritated seborrheic keratoses. Treatment for inverted follicular keratosis is the complete removal of the lesion, with excellent prognosis, almost without recurrence.

A Case of Nevus Sebaceus, Accompanied by Syringocystadenoma Papilliferum, a Basal Cell Carcinoma-like Tumor, Sebaceous Epithelioma, Apocrine Adenoma and Tumor of Follicular Infundibulum, with Repair by Subgaleal-periosteal Fixation / 대한피부과학회지

Nevus sebaceus is well-known for its potential to develop both benign and malignant neoplasms of epidermal and adnexal origin. We found 5 tumors including syringocystadenoma papilliferum, a basal cell carcinoma-like tumor, sebaceous epithelioma, a tumor of follicular infundibulum and apocrine adenoma within a single nevus sebaceus lesion in a 37-year-old man. This is a rarely reported case of a nevus sebaceus lesion containing a basal carcinoma-like, trichoblastoma-like skin tumor and tumors of follicular infundibulum. The lesion was treated by wide excision and repaired with subgaleal-periosteal fixation which resulted in good wound healing.

Two Cases of Tumor of Follicular Infundibulum / 대한피부과학회지

Tumor of the follicular infundibulum(TFI) is a rare benign adnexal tumor originating from the infundibular portion of hair follicle. Majority of the lesions have been solitary and not recognized clinically before biopsy. TFI can be classified as follows according to the clinical presentation of the tumor (1) solitary tumor, (2) eruptive tumors, (3) TFI associated with other lesions of Cowden's disease, (4) TFI arising in nevus sebaceus, and (5) TFI-like changes in various tumors. We present clinicopathologic features of 2 cases of TFI. One was a solitary form and the other was associated with nevus sebaceus.

Tumor of Follicular Infundibulum / 대한피부과학회지

Tumor of follicular infundibulum is the term coined by Mehregan and Butler in 1961 for a benign hyperplastic lesion that extends from the follicular infundibulum as an epithelial plate with underlying elastic fiber network. This tumor appears as a slightly elevated keratotic lesion and is characterized histologically by proliferation of follicular sheath epithelium in the form of a thin subepidermal plate. We present a typical case of tumor of follicular infundibulum in the left shoulder area of 74 year-old-man. To the best of our knowledge, this is the first reported case of a solitary tumor of follicular infundibulum in Korea.

A Case of Tumor of Follicular Infundibulum Associated with Nevus Sebaceus / 대한피부과학회지

Tumor of the follicular infundibulum is a rare benign adnexal tumor originating from the infundibular portion of hair follicle and the majority of lesions have been solitary and not recognized clinically before biopsy. A 28-year-old female presented with a bean-sized hairless yellowish plaque on the right upper eyebrow, clinically diagnosed as nevus sebaceus. After complete excision, histopathologic examination of the specimen revealed a focal circumscribed subepidermal tumor roughly parallel to the epidermis, composed of proliferation of pale-staining cells containing diastase-labile PAS(+) glycogen, enclosed by a palisaded basal layer with underlying lesion of nevus sebaceus. Upper dermis directly beneath the tumor had accentuated elastic fiber network outlining the tumor base in the elastic stain.

A Case of a Tumor of the Follicular Infundibulum-like Change in Nevus Sebaceus / 대한피부과학회지

Cribier and Grosshans(1995) reported two cases of tumor of the follicular infundibulum(TFI) arising in nevus sebaceus for the first time. In 1961 Mehregan and Butler described a new benign adnexal neoplasm, which they called tumor of the follicular infundi4ulurn." Since then few observations have been published. The majority of the lesions are solitary. They appeared in adults, predominantly in wornen, on the face, arm, and neck. Histopathologically, the unique feature is a benign hyperplastic lesion that extends from the follicular infundibuluni. as an epithelial plate either with underlying elastic fiber network in TFI or without underlying elastic fiber network in TFI like change. A 52-year-old man has haf a solitary, well-defined, hairless, verrucous plaque on his right supra auricular area for about 10 years. It has seerned to increase gradually in size over the last year. The histologic findings shwed a plate-like growth of epithelial cells in the upper dermis extending parallel to the epidermis with multiple connections at the lower margin of the epidermis. The peripheral cell layer of ttie tumor plate showed palisading, and centrally located cells were pale staining. Many hair follicl s, mature sebaceous glands, ectopic apocrine glands, and inflammatory cell infiltrations were present in the dermis. However, there was no elastic fiber network beneath the epithelial cell plate. We believe our case is the first to be reported in Korea as TFI-like change in nevus sebaceus.

Tumor of Follicular Infundibulum

We report a case of a tumor of the follicular infundibulum in a 54-year-old woman who had a papule on the medial side of the right upper eyelid for four months. Histopathologic findings were characterized by proliferation of follicular infundibular epithelium in the form of a thin subepidermal plate and small hair follicles in the tumor plate.