Cutaneous lymphadenoma is distinct from basal cell carcinoma

Background Cutaneous lymphadenoma is a recently recognized unusual tumor. It presents as an indistinct solitary non-ulcerating dermal nodule occuring mostly in the head and neck region of middle aged persons. Its histogenetic definition is controversial and recently it has been proposed that it might represent an unusual inflammatory basal cell carcinoma. We present clinical, hislological and immunohistochemistry data of two cases. For the first time lectin-imrnunohistochemisiry of cutaneous lymphadenoma is reported on. Observations One tumor was located on the eyebrow of a 37 years old, the other on the nose of a 75 years old male patient. Slow growth over years occured. Histology showed biphasic pattern of elongated and angulated lobules with peripheral rim of basaloid cells and central network of lymphohisltocytic cells with preponderance of protein S 100-positive cells. Peanut agglutinin (PNA) did not show peripheral staining around tumor lobules as seen in basal cell carcinoma. Conclusions Clinical and histological features as well as absence of peanut agglutinin staining argue in favor of the distinction of cutaneous lymphadenoma from inflammatory basal cell carcinoma. The former probably represents a benign growth of adnexal origin.     

Trichoblastomas with Merkel cell proliferation in nevi sebacei in Schimmelpenning‐Feuerstein‐Mims syndrome – Histological differentiation between trichoblastomas and basal cell carcinomas

The hallmark of Schimmelpenning‐Feuerstein‐Mims syndrome (SFMS) is a systematized nevus sebaceous that follows Blaschko lines and usually involves the face. It represents a rare congenital nevus syndrome with alterations of skin, bones, CNS, eyes and heart. Nevi sebacei can proliferate and develop into epithelial tumors like trichoblastoma, syringocystadenoma and basal cell carcinoma. The histological differentiation between basal cell carcinoma and trichoblastoma is difficult. We present an adult woman with SFMS who was followed by multiple specialties since birth without the correct diagnosis being made. She was referred to us with the diagnosis of multiple basal cell carcinomas of head and face. Our diagnosis of systematized nevus sebaceus was crucial for the correct classification of SFMS. We identified multiple trichoblastomas in the nevi sebacei and could exclude basal cell carcinomas. The essential clue was the detection of multiple Merkel cells within the epidermal layer by cytokeratin 20 staining.     

Nestin expression in stromal cells of trichoblastoma and basal cell carcinoma

Background Both trichoblastoma and basal cell carcinoma (BCC) are considered to be a benign and malignant neoplasm of follicular germinative cells respectively. A recent investigation revealed that the mesenchymal cells in the perifollicular sheath and evolving follicular papilla of embryonic hair germs and those cells in hair follicles in early anagen express nestin. Objective The aim of the present study was to investigate whether trichoblastoma and BCC recapitulate the epithelial–mesenchymal interactions in embryonic hair germs or early anagen hair follicles by expressing nestin in stromal cells. Methods Immunohistochemical staining was performed with antibody against nestin for 15 trichoblastomas including large/small nodular, retiform and trichoepithelioma types, while adding the superficial type associated with nevus sebaceous and for 20 BCCs including superficial, nodular, nodulo‐infiltrative, and infiltrative/micronodular types. Results In all 15 trichoblastomas, the stromal cells expressed nestin with variable positive reactions, except for superficial trichoblastomas within nevus sebaceous lesions, in which stromal cells were constantly positive for nestin. In all 20 BCCs, the stromal cells were basically negative for nestin. Conclusions The development of trichoblastomas incompletely recapitulates the epithelial–mesenchymal interactions in embryonic hair germs or early anagen hair follicles, whereas BCCs fundamentally have lost this ability. Among the various types of trichoblastomas, the superficial type associated with nevus sebaceous was found to have the most similar character to either embryonic hair germs or early anagen hair follicles.     

Congenital cutaneous lymphadenoma

Cutaneous lymphadenoma is an uncommon benign neoplasm often considered to be an adamantinoid variant of trichoblastoma. Lesions present in both sexes, between 14 and 87 years of age, and are mainly located on the head and neck. Cases in children are rare and there is only 1 previous case of a congenital lymphadenoma. An 8‐year‐old Asian girl presented with a congenital lesion on her forehead comprising 4 pink papules, the largest 5 mm in diameter. Microscopy revealed a well‐circumscribed tumor within the dermis and subcutis comprising well‐demarcated epithelial lobules of basaloid and clear cells with subtle peripheral palisading, growing in a collagenous stroma but lacking retraction artefact. A relatively dense accompanying predominantly lymphocytic inflammatory cell infiltrate including both T‐cells (CD3+) and B‐cells (CD20+) permeated the nodules and spilled into the stroma. CD68+ histiocytes and CD1a+ Langerhans cells were moderately numerous. This is the second case of congenital lymphadenoma which—in spite of its rarity in childhood—widens the diagnostic possibilities of cutaneous lymphoepithelial tumors in children.     

皮脂腺痣并发毛母细胞瘤

报告1例皮脂腺痣并发毛母细胞瘤。患者女,39岁。出生即发现右侧耳周芝麻至粟粒大褐色丘疹。皮肤科检查:右侧耳前部可见条带状斑块,呈蜡样光泽,其上有结节,局部糜烂及结痂;右侧耳后部可见密集分布的蜡黄或棕褐色角化性丘疹或斑块,边界清楚。皮损组织病理检查:表皮突延伸,区域表皮长出多个原始的毛乳头样结构,周边细胞呈栅栏状排列;真皮层可见结节状的毛母细胞瘤以及大量皮脂腺结构,下方无毛囊。诊断:皮脂腺痣并发毛母细胞瘤。治疗:予手术切除。     

Tumors associated with nevus sebaceous

Background: Nevus sebaceus (NS) is a congenital hamartomatous lesion, usually involving the scalp or the face. Various benign and malignant neoplasms can develop in association with NS, the most common being trichoblastoma, syringocystadenoma papilliferum, viral warts and basal cell carcinoma (BCC). Patients and methods: We retrospectively examined the clinical and histopa‐thological records of 15 NS cases with an associated tumor which were diagnosed between 1996 and 2004. Results: All cases were adults and 3 of them had more than one tumor. Six cases had BCC, which is a higher incidence of malignant tumor association with NS, than that reported in last years. Trichoblastoma was observed in 3 cases and was the most common benign tumor in our series. Filiform, hyperkeratotic, pigmented, pedunculated and/or eroded papulonodular changes were major clinical signs of secondary tumors on NS in our series. Conclusion: Clinical features are not sufficient enough to make an exact diagnosis of benign or malignant secondary tumors. Though prophylactic excision for NS is done less in last years, especially adult patients should closely be followed for any new changes evoking tumor development on this congenital lesion.     

Collision tumour of trichofolliculoma and basal cell carcinoma

A 52-year-old woman presented with a 2-year history of a reddish nodule on the right nasolabial sulcus. Histopathological examination revealed that the nodule was composed of trichofolliculoma and basal cell carcinoma. There was no transitional zone between the two neoplasms. The diagnosis was made as a collision tumour of trichofolliculoma and basal cell carcinoma.     

Multiple pigmented trichoblastomas and syringocystadenoma papilliferum in naevus sebaceous mimicking a malignant melanoma: a clinical dermoscopic-pathological case study

We report a case of three distinct adnexal neoplasms associated with a naevus sebaceous of the scalp: a nodular pigmented trichoblastoma, a smaller flat pigmented trichoblastoma and a syringocystadenoma papilliferum, and discuss the clinical and histological features of these neoplasms. The clinical manifestation was suggestive of malignant melanoma, a feature that has never been reported before. For the first time in the literature we describe the case also by means of a noninvasive analysis, i.e. epiluminescence microscopy. In our experience, epiluminescence microscopy does not appear to be more diagnostically accurate than simple clinical examination when diagnosing lesions of the scalp, contrary to other regions.