๐ ็ธฝ็ฎ้ ๏ฝ ๐ ่ฑๆๅๆ๏ผๆฌ็ฏ๏ผ ๏ฝ ๐ ๅฎๆด็ฟป่ญฏ ๏ฝ โญ ็ฒพ่ฏ็ญ่จ
Kaposi sarcoma
Kaposi sarcoma
Clinical features Prior to the HIV/acquired immunodeficiency syndrome (AIDS) era, Kaposi sarcoma (KS) was a rare malignancy of the conjunctiva that mainly occurred in elderly, immunosuppressed patients. It is now encountered mostly in patients with AIDS, usually late in the course of the disease, although conjunctival KS may be the first sign of HIV/AIDS.1 Rarely, KS may appear in HIV negative, non-immunosuppressed patients.2โ4
Conjunctival KS may be single or multiple, and appear as a dark red to purple painless lesion that may be initially mistaken for a subconjunctival hemorrhage. As it grows it may become elevated and nodular, causing irritation and foreign body sensation. The patient may have KS lesions elsewhere on the body.
Clinical features Fibroma and solitary fibrous tumor are rare in the conjunctiva.1,2 Clinically, fibroma appears as a white stromal mass. In the periocular region, solitary fibrous tumor more commonly occurs in the orbit. In the one reported case of conjunctival solitary fibrous tumor, the lesion was a well-circumscribed, firm pink mass in the fornix.2
Histologic features Microscopically, fibroma is composed of dense fibrous connective tissue with bland appearing mesenchymal cells compressed between parallel layers of collagen lamellae.1 There is no significant vascularity or inflammation. The cells have fibroblast features by immunohistochemistry (vimentin positive; S100 protein, smooth muscle actin, CD34, and CD99 negative).1
Histologic features Similar to KS elsewhere, it is composed of spindle-shaped cells with elongated oval nuclei and slit-like vascular channels lined by bland endothelial cells. By immunohistochemistry, tumor cells are positive for vascular markers, such as CD31, Erg, and CD34, as well as human herpesvirus (HHV)-8.3