FGFR3 and PIK3CA mutations in stucco keratosis and dermatosis papulosa nigra

Background Stucco keratosis (STK) and dermatosis papulosa nigra (DPN) are referred to as variants of seborrhoeic keratosis. However, the genetic alterations involved in the pathogenesis of these benign tumours are unknown. Objectives Because FGFR3 and PIK3CA mutations have been reported to be involved in the pathogenesis of seborrhoeic keratosis, we analysed whether these mutations are also present in STK and DPN. Methods A SNaPshot^® multiplex assay was used for analysis of 11 previously described FGFR3 hotspot mutations. PIK3CA mutations were analysed by a SNaPshot^® assay covering five PIK3CA hotspot mutations. Results Five STK and two DPN samples were analysed. Three of five STK samples revealed a PIK3CA mutation (E542K, E545K), but no FGFR3 mutation was found. In contrast, both DPN samples harboured an FGFR3 mutation (R248C, S249C) but no PIK3CA mutation. Control tissues available for three samples did not show PIK3CA or FGFR3 mutations, excluding germline mutations and indicating a strong genotype–phenotype correlation between the mutation and the lesion. Conclusions These results indicate that FGFR3 and PIK3CA mutations are involved in the pathogenesis of STK and DPN. The molecular genetic findings furthermore support the concept that both skin lesions are specific variants of seborrhoeic keratosis, sharing a common genetic background.     

黑色丘疹性皮病一例

患者女,36岁,胸腹部多发黑褐色丘疹10余年,逐渐增多。体检：前胸、腹部皮肤可见散在数十个黑褐色扁平丘疹,直径1 ～ 3 mm,表面光滑,部分呈乳头瘤样,无融合。腹部皮损组织病理检查：表皮轻度角化过度,棘层增厚,皮突延长,互相连接成网状,棘层内可见假性角囊肿形成,基底层色素增加,真皮浅层血管周围稀疏淋巴组织细胞浸润。诊断：黑色丘疹性皮病。     

黑色丘疹性皮病

报告1例黑色丘疹性皮病.患者女,28岁.双颧部出现褐色丘疹7年,皮损渐增多、增大,无自觉症状.皮肤科检查:双颞颧部对称性散在分布米粒至绿豆大棕色或深褐色扁平丘疹,直径1～5 mm,触之柔软.皮损组织病理检查:表皮角化过度,棘层轻度增厚,表皮突延长,相互连成网状,棘层可见2个角质囊肿,真皮浅层小血管周围少量淋巴细胞浸润.     

The "sign of groove", a new cutaneous sign of internal malignancy

A 36-year-old young male with multiple heterosexual contacts presented with bilateral inguinal bubo and the classical "sign of groove". A diagnosis of lymphogranuloma venereum (LGV) was made and a three-week course of doxycycline was given. Lack of response prompted us to investigate further. A biopsy of the bubo was consistent with non-Hodgkin's lymphoma (NHL). Immunohistochemistry of the lymph node done at the Regional Cancer Center (RCC), Trivandrum, confirmed the diagnosis as NHL of diffuse large B-cell type. The second patient, a 32-year-old male with two unprotected heterosexual contacts presented with a left-sided inguinal bubo of six weeks duration. An empirical course of doxycycline was given even though investigations did not reveal any STI. Lack of response prompted us to do a lymph node biopsy, which was consistent with NHL, which later with immunohistochemistry was confirmed as NHL, diffuse large cell type. We are reporting here that the "sign of groove" is not specific for LGV as thought earlier, but can occur in NHL also.     

Tripe palms: a significant cutaneous sign of internal malignancy.

Tripe palms is a paraneoplastic keratotic skin sign of great predictive value. It is characterized clinically by a curious rugose thickening of the palms with an accentuation of the normal dermatoglyphic ridges and sulci. Histological examination reveals an undulant epidermis with hyperkeratosis, acanthosis and papillomatosis. More than 80 cases have been reported in the literature; 90% of them were associated with an internal malignancy, mostly a carcinoma of the lung or stomach. We herein report a 66-year-old Chinese man with adenocarcinoma of the lung who presented typical tripe palms. Recognition of this distinctive pattern should prompt a meticulous search for an underlying malignancy, particularly lung or gastric carcinoma.     

Eosinophilic dermatosis of hematologic malignancy

Cutaneous involvement by an eosinophil-rich process (eosinophilic dermatosis) may be encountered in the setting of various hematologic malignancies, including mantle cell lymphoma, acute monocytic leukemia, acute lymphoblastic leukemia, large cell lymphoma, myelofibrosis and chronic lymphocytic leukemia (CLL). Of the various hematologic malignancies, eosinophilic dermatosis has been most frequently described in association with CLL. Published previously as insect bite-like reaction and eosinophilic dermatosis of myeloproliferative disease, this rare dermatitis presents as a pruritic, papular and occasionally vesicular eruption associated with an eosinophil-rich infiltrate histopathologically. Although clinical and histopathologic features are similar to insect bites, affected patients frequently deny a history of insect bites. We report a case of eosinophilic dermatosis of hematologic malignancy in a patient with known history of CLL.     

Multiple leiomyoma as a possible sign of aggressive renal cancer

A 53-year-old Chinese man presented with a history of painful lesions on the chest of 20 years' duration. He experienced sharp pain especially on touching and after spicy food. The lesions were stable with no increase in size or number. He was otherwise well. There was no significant family history. Physical examination revealed multiple, grouped, pink papules on the left chest, extending to the right back in a segmental distribution, each measuring 2-5 mm (Figs 1 and 2). They appeared pearly and keloid-like, and had a firm consistency. A punch biopsy specimen was obtained and sent for histopathologic examination (Figs 3 and 4). This revealed a circumscribed, nonencapsulated tumor with a Grenz zone below the epidermis. It was composed of interlacing fascicles of bland spindle cells with elongated nuclei and blunt ends, typical of a cutaneous leiomyoma. The patient subsequently underwent computed tomography of the abdomen, which did not show any renal or abdominal masses.     

Mitotic Langerhans cell as a possible sign of activation in ichthyosis

The fine structure of Lagerhans cells (LC) in four rare types of ichthyosis, namely recessive ichthyosis congenita type II, III and IV and ichthyosis hystrix Curth-Macklin was examined. Signs of LC activation were observed in eight of 21 patients. In IC type IV, the rare occurrence of a mitotic LC was observed. It is possible that LCs are secondarily activated in keratinization disorders.     

Eczema craquelé as a pointer of internal malignancy - A case report

A case of eczema craquelé associated with gastric adenocarcinoma is reported. There are localized and generalized forms of eczema craquelé, the generalized forms differing from the localized types because they can he signs of metabolic or internal disease such as cancer. The patterns of the condition are reviewed based on the literature and personal observations.