Cutaneous Malignant Squamomelanocytic Tumor: A Case Report of a Rare Neoplasm.

ABSTRACT: Cutaneous squamomelanocytic tumor (SMT) is an exceedingly rare cutaneous malignancy characterized by the presence of both squamous cell carcinoma and malignant melanoma within a single tumor. SMT typically presents clinically as keratotic skin papulonodules, most commonly occurring on the face, scalp, or other sun-exposed areas of middle-aged to elderly White male patients. Owing to the rare nature of this tumor, the histogenesis and prognosis remain relatively unclear. Histopathological examination of the tangential biopsy revealed an invasive cutaneous malignancy consisting of 2 distinct yet closely associated atypical cell populations: (1) a population of atypical squamoid epithelial cells arranged in cords and keratin pearls and (2) a population consisting of atypical, spindled cells with fine melanin pigment arranged in confluent sheets. Both populations of atypical cells emanated in an invasive pattern from the underside of the overlying epidermis into the deep dermis. Squamomelanocytic tumors are among the rarer types of collision tumors between 2 malignant lesions as most are basomelanocytic. For most reported SMTs, the melanoma population comprises epithelioid cell morphology, whereas our tumor is composed of spindled cell morphology. In this article, we exemplify a unique case of SMT in an 87-year-old male patient.

Topical tacrolimus therapy in the management of lower extremity ulcers due to prolidase deficiency.

Prolidase deficiency is a rare autosomal recessive disorder characterized by cutaneous ulcers, facial dysmorphism, recurrent infections, and intellectual disability. We report a unique case of a 6-year-old boy with prolidase deficiency and Crohn's disease who presented with lower extremity ulcers. Cutaneous ulcers due to prolidase deficiency are historically resistant to treatment, and we report success with the novel use of topical tacrolimus.

Use of Topical and Systemic Retinoids in Solid Organ Transplant Recipients: Update and Review of the Current Literature.

BACKGROUND: Solid organ transplant recipients (SOTRs) are at an increased risk of epithelial malignancies, mainly squamous cell carcinoma, and its precursor lesions such as actinic keratoses, warts, and porokeratosis, which may respond to retinoid therapy. OBJECTIVE: To review the published evidence on the efficacy and safety of topical and systemic retinoids for the treatment and prophylaxis of malignant and premalignant conditions that mostly afflict SOTRs. MATERIALS AND METHODS: Systematic review of the literature to summarize the level of evidence and grade of recommendation for retinoid therapy with emphasis in the SOTR population. RESULTS: Acitretin has the highest strength of recommendation (Grade A) for prophylaxis of nonmelanoma skin cancer (NMSC) and treatment and prophylaxis of actinic keratoses in SOTR. In nonimmunosuppressed patients, acitretin and isotretinoin have a Grade B recommendation for treatment of recalcitrant warts. Topical retinoids have not shown efficacy in preventing NMSC in immunocompetent patients. CONCLUSION: Retinoids constitute a highly efficacious alternative for the management of the most common conditions that affect SOTRs. Acitretin has the most robust evidence for chemoprophylaxis in SOTRs. Knowledge about the specific indications and expected side effects of topical and systemic retinoids may help optimize their therapeutic potential.

Collagenous and elastotic marginal plaques of the hand: A potential clue to the diagnosis of alkaptonuria.

Collagenous and elastotic marginal plaques of the hand (CEMPH) is a rare, chronic keratoderma characterized by hyperkeratotic linear plaques located along the radial and ulnar aspects of the hands bilaterally. As an isolated finding, CEMPH occurs secondarily to chronic trauma and photodamage. Herein, CEMPH is described as a manifestation of alkaptonuria (AKU). In addition to keloidal collagen, ochronotic fibers and fragmented, thickened elastic fibers were observed. Additionally, mucin deposition-not previously described in this clinical context-was also identified. Given their overlapping clinicopathologic features, CEMPH due to AKU should be distinguished from the acquired variant as well as acrokeratoelastoidosis.

Callosal disconnection neglect: reassessment after 34 years.

In 1984, Watson and Heilman reported a patient with a partial callosal disconnection following an infarction of the anterior portion of her corpus callosum. This woman's performance on line-bisection tasks revealed "callosal disconnection neglect." The objective of this research is to reexamine this woman 34 years after her callosal disconnection to gain information about her recovery. The patient completed visual line-bisection tasks in which horizontal lines were placed in the right, left, and center hemispaces and she performed these bisections using her right or left hand. Unlike her performance 34 years ago in which each hand deviated to its ipsilateral hemispace, with greater deviation when lines were placed in the contralateral rather than ipsilateral hemispace, currently, there were no significant main effects for hand or spatial position. Thus, there were notable differences between this woman's most recent performance on the line bisection and her previous performance 34 years ago. Unlike her prior testing 34 years back, this woman's most recent performance resembled the performance of a previous tested healthy control group for whom differences in hand and hemispace were not found. It remains unclear whether her callosal disconnection neglect improved because each hemisphere learned to allocate ipsilateral spatial attention or because she learned a compensatory strategy in which she turned her body so that the lines placed in her right or left hemispace were now toward her midline.