Spindle Cell-Predominant Trichodiscoma With Palisading Arrangement: A Rare Variant.

ABSTRACT: Spindle cell-predominant trichodiscoma (SCPT) is a benign adnexal neoplasm, best categorized within the trichodiscoma-fibrofolliculoma continuum. SCPTs clinically present as dome-shaped papules usually on the face, particularly on the nose or the nasolabial fold. The SCPT variant has been described as a particularly cellular trichodiscoma composed of small interweaving fascicles and sheets of spindle cells. Identical lesions were previously referred to as neurofollicular hamartomas because of their predominantly fascicular stromal cellularity and focal S100 positivity. In this article, we report a rare variant of SCPT with a palisaded arrangement. The patient is a middle-aged man with no significant dermatologic history who presented with a skin-colored papule on the left nasal ala. It had been present for approximately 10 years with only minimal growth over that time. A biopsy was obtained. Histopathological analysis revealed a dermal papule composed of bland spindle cells arranged in a striking palisading pattern within a fibromyxoid stroma with associated peripheral hyperplasia of sebaceous glands. The palisaded pattern shared features reminiscent of Verocay bodies of a schwannoma. Immunohistochemical studies revealed stromal spindled cells with a strong and diffuse pattern of CD34 expression and absent S100 and SOX10 expressions. To our knowledge, only 2 cases of SCPT with a palisaded pattern have been presented. SCPT with a palisaded pattern is a rare histopathologic variant that may resemble a schwannoma but can be recognized by its strong epithelial components and immunohistochemical staining pattern.

Prevalence and Types of Genital Lesions in Organ Transplant Recipients.

Importance: Squamous cell carcinoma (SCC) is the most common skin cancer diagnosed in solid organ transplant recipients (OTRs) and confers significant mortality. The development of SCC in the genital region is elevated in nonwhite OTRs. Viral induction, specifically human papillomavirus (HPV), is hypothesized to play a role in the pathophysiology of these lesions. Objective: To assess the prevalence and types of genital lesions observed in OTRs. Design, Setting, and Participants: This retrospective review included 496 OTRs who underwent full skin examination from November 1, 2011, to April 28, 2017, at an academic referral center. The review was divided into 2 distinct periods before a change in clinical management that took effect on February 1, 2016 (era 1) and after that change (era 2). Patient awareness of genital lesions was assessed. All lesions clinically suggestive of malignant tumors were biopsied and underwent HPV polymerase chain reaction typing. Main Outcomes and Measures: Number and types of genital lesions, proportion of malignant tumors positive for HPV, and patients cognizant of genital lesions. Results: Of the total 496 OTRs, 376 OTRs were evaluated during era 1 (mean [SD] age, 60 years; age range, 32-94 years; 45 [65.2%] male; 164 [43.6%] white) and 120 OTRs were evaluated during era 2 of the study (mean age, 56 years; age range, 22-79 years; 76 [63.3%] male; 30 [25.0%] white). Overall, 111 of the 120 OTRs (92.5%) denied the presence of genital lesions during the history-taking portion of the medical examination. Genital lesions were found in 53 OTRs (44.2%), cutaneous malignant tumors (basal cell carcinoma and SCC in situ) in 6 (5.0%), genital SCC in situ in 3 (4.2%), and condyloma in 29 (24.2%). Eight of the 12 SCC in situ lesions (66.7%) were positive for high-risk HPV. Seven tested positive for HPV-16 and HPV-18, and 1 tested positive for high-risk HPV DNA but could not be further specified. Conclusions and Relevance: Genital lesions in OTRs are common, but awareness is low. All OTRs should undergo thorough inspection of genital skin as a part of routine posttransplant skin examinations. Patients with darker skin types are disproportionately affected by cutaneous genital malignant tumors and should undergo a targeted program of early detection, prevention, and awareness focused on the risk of genital skin cancer after transplant. High-risk HPV subtypes are associated with genital SCC in OTRs. Additional studies are warranted to identify significant risk factors for HPV infection and to assess the utility of pretransplant HPV vaccination in the prevention of cutaneous genital malignant tumors.