Line‐field confocal optical coherence tomography for actinic keratosis and squamous cell carcinoma: a descriptive study

Abstract

Background. Early and accurate diagnosis of cutaneous squamous cell carcinomas (SCCs) and actinic keratoses (AK) is fundamental to reduce their associated morbidity and to select the correct treatment. Line-field confocal optical coherence tomography (LC-OCT) is a new imaging device that can characterize healthy skin and basal cell carcinoma, but no large studies on keratinocyte cell tumours have yet been published. Aim. To identify and describe LC-OCT criteria associated with SCC and AK, and to compare LC-OCT findings in these tumours. Methods. A retrospective observational multicentre study was conducted. Lesions were imaged with the LC-OCT device before surgery and examined histologically. LC-OCT criteria for AK/SCC were identified and their presence was evaluated in all study lesions. Univariate and multivariate analyses were performed to compare AK and SCCs, and to investigate differences between in situ and invasive tumours. Results. In total, 158 patients with 50 AK and 108 SCCs (62 in situ and 46 invasive) were included. Cytological and architectural alterations were found in most lesions, and differences were found between AK and SCCs. Although the visualization of the dermoepidermal junction (DEJ) was often hampered by hyperkeratosis and acanthosis, an outlined DEJ without broad strands was observed in almost all AK and almost all in situ SCCs, but in only three invasive SCCs (P < 0.001) when the DEJ was detectable. Conclusion. Our results suggest that LC-OCT can help clinicians in the identification of AK and SCC and their differentiation, providing a real-time and noninvasive examination. Further studies are needed to confirm our data.

Line‐field confocal optical coherence tomography of basosquamous carcinoma: a case series with histopathological correlation

“…In line with a previous investigation, 10 dermal lobules featuring the peculiar millefeuille pattern (corresponding to basaloid tumour islands), bright cells within the epidermis (corresponding to immunologically competent skin cells and activated melanocytes) and dilated vessels represented the main BCC-associated LC-OCT criteria for BSC. In agreement with previous data, 11 acanthosis and disarranged epidermal architecture with hyperkeratosis represented the leading SCC-associated LC-OCT features of BSC.…”

“…Tumour-related neoangiogenesis could be observed both in the form of dilated vessels (BCC-associated feature) and glomerular vessels (SCC-associated feature). 10,11 When comparing LC-OCT horizontal modality with RCM images of BSC published by Oliveira et al, 7 a similar level of detail was observed thanks to the high resolution provided by LC-OCT, which is in our opinion unprecedented in the OCT field. In addition, LC-OCT also provides vertical images that are often able to show cyto-architectural disarray up to the lower border of the tumour, thus, providing useful information on tumour size and thickness.…”

“…DEJ no longer visible as a continuous hyporeflective small band) was appreciated in most cases and was due either to broad strands of atypical epidermal keratinocytes infiltrating the underlying dermis (SCC‐associated feature) or to the presence of lobules featuring the millefeuille pattern that are intimately connected to the epidermis (BCC‐associated feature). Tumour‐related neoangiogenesis could be observed both in the form of dilated vessels (BCC‐associated feature) and glomerular vessels (SCC‐associated feature) 10,11 …”

Line-Field Confocal Optical Coherence Tomography: A New Tool for the Differentiation between Nevi and Melanomas?

“…The disadvantage of LC-OCT is the lower penetration depth compared to OCT, so it is possible that deeper tumor parts may be missed [19,20]. Due to the presentation of single cells, differential diagnoses such as sebaceous hyperplasia, actinic keratoses, and squamous cell carcinomas could be differentiated, and the proliferation degree of actinic keratoses showed a 75% concordance between LC-OCT and histology [21][22][23][24]. This high single cell resolution is the reason why we assumed that even melanocytic lesions can be evaluated with LC-OCT.…”

Non-Melanoma Skin Cancer Clearance after Medical Treatment Detected with Noninvasive Skin Imaging: A Systematic Review and Meta-Analysis

“…SCC are typified by atypical honeycombed patterns in dermoscopy, which correspond to atypical keratinocytes, dark areas with sharp and irregular contours in RCM, which correspond to ulceration, and irregular dilated vessels in RCM [ 20 , 21 , 22 ]. SCC is characterized in OCT by a thickened epidermal layer, which may hamper the visualization of the underlying structures, and a loss of clear demarcation of the DEJ, which is considered an indication of invasive disease [ 23 , 24 ].…”