Transforming the treatment of psoriasis to the 21st century: Detecting subclinical therapeutic response to secukinumab using optical coherence tomography as a prognostic indicator.

BACKGROUND: Optical coherence tomography (OCT) is a noninvasive imaging device that scans the skin up to 2 mm in depth. OCT can capture real-time epidermal thickness (ET) measurements and detect subclinical changes in inflammatory skin diseases like eczema and psoriasis. © 2022 Wiley Periodicals LLC. OBJECTIVE: To determine if measuring ET with OCT can detect a subclinical therapeutic response in psoriasis treated with the biological therapy, secukinumab (an IL-17A antagonist). DESIGN: Phase IV, single-center, open-label, and single-arm study. PARTICIPANTS: Twenty-six consecutive patients with moderate to severe plaque psoriasis. MEASUREMENTS: Clinical, dermoscopic, and OCT images were obtained at each visit. The clinician measured disease severity with the Investigator's Global Assessment (IGA) and Psoriasis Area And Severity Index (PASI). OCT was used to scan the ET at the center of lesional skin (ET-L), along the border, and normal skin (ET-N) on the same body plane; their difference was noted as ΔET. RESULTS: Initially, ET-L was greater than ET-N (p < 0.0001), their differences decreased throughout the study, and there were no significant differences at Week 16 (p = 0.48). Twenty-four (92%) patients achieved a 50% reduction in PASI score (PASI50); they had lower ΔET at Weeks 0, 1, 3, 4, and 8 compared to those who did not clear (p < 0.04). Having a lower ΔET at Week 4 was associated with a shorter time to reach PASI50 (p = 0.02). CONCLUSION: ET measurements using OCT can detect an early subclinical response to secukinumab compared to clinical scoring and identify nonresponders as early as 4 weeks.

Combining Reflective Confocal Microscopy and Dynamic Optical Coherence Tomography to Diagnose Melanoacanthoma: Case Report.

ABSTRACT: Few reported cases discuss distinguishing between melanoma and melanoacanthoma, a seborrheic keratosis (SK) variant, using noninvasive imaging devices. We present a case of a 38-year-old man with Fitzpatrick skin type IV with an asymmetric black papule showing clinical and dermoscopic features of both melanoma and SK. Reflectance confocal microscopy (RCM) and dynamic optical coherence tomography (d-OCT) were used for further evaluation. RCM revealed acanthotic epidermis with a mixed honeycomb and cobblestone pattern, polycyclic bulbous rete ridges, and bright plump cells within entrapped, edged, dermal papillae, compatible with pigmented SK. Also noted were a population of fairly uniform bright dendritic cells scattered quite evenly at all levels of the epidermis and the notable absence of concomitant features of a melanocytic neoplasm (roundish Pagetoid cells, sheets of roundish or dendritic cells at the dermal-epidermal junction, junctional thickenings, and melanocytic nests), suggesting melanoacanthoma. d-OCT showed well-circumscribed, regular, epidermal acanthosis, superficial rounded hypodense structures, normal vascular flow, and notable absence of wiry or contoured vessels, features typically seen in SKs and benign lesions, respectively. Similarly, histologic examination revealed characteristics of pigmented SK containing a population of evenly dispersed dendritic melanocytes (decorated using Melan-A stain) confirming a diagnosis of melanoacanthoma. This case highlights the advantages of incorporating both RCM and d-OCT into clinical practice to noninvasively differentiate melanoma from its clinical mimickers.