OCT and Invasion in Cutaneous Skin Lesions

Study Overview
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Brief Summary
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The increasing incidence of actinic keratosis (AK), morbus Bowen (MB) and cutaneous squamous cell carcinoma (cSCC), the patients with often multiple lesions and the disadvantages of invasive diagnostics show the need for an accurate non-invasive diagnostic tool for the determination of invasive growth in AK and MB. Optical coherence tomography (OCT) is a non-invasive scanner creating cross-sectional images of the skin, to a depth of 1-1,5 mm based on light waves. Until now, OCT has been proposed as non-invasive diagnostic tool for basal cell carcinomas. Although the diagnostic value of OCT for detection and sub-typing of basal cell carcinomas has already been demonstrated, it is unclear whether OCT can discriminate between invasive and non-invasive lesions (AK, MB and cSCCs). There are some studies that describe OCT characteristics of AK, MB and cSCCs, however, these characteristics have a lot of overlap (8-13). To date there are no clearly distinctive OCT features to distinguish between AK, MB and cSCCs. This study aims to investigate the value of OCT in discriminating between the presence and absence of invasion in lesions with clinical suspicion for invasion. Two experienced OCT-assessors will evaluate the OCT scans independently. The OCT assessors are blinded to the histological diagnosis of the lesions (invasive or non-invasive), which is used as golden standard. A 5-point Likert scale is used for OCT assessment. Definitely not invasive Probably not invasive Unknown, probably invasive/probably not invasive Probably invasive Definitely invasive In addition to completing the Likert-scale, assessors are asked to describe the presence/absence of predefined OCT characteristics (a.o. hyperkeratosis and the presence of the dermo-epidermal junction) In case of disagreement between the independent assessors, the OCT scan will be re-assessed in a consensus meeting.

Official Title
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The Value of Optical Coherence Tomography in Discrimination Between the Presence and Absence of Invasion in Clinical Actinic Keratosis

Conditions
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Cutaneous Squamous Cell Carcinoma, Bowen's Disease, Actinic Keratoses, Keratosis, Actinic, Diagnosis

Intervention / Treatment
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* Diagnostic Test: Optical Coherence Tomography
* Other: Clinical assessment


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients who are included in a previous study on OCT, with written informed consent to use their data regarding OCT. Patients who retrospectively had an OCT scan for their skin lesion With a histological confirmed actinic keratosis, bowens disease or cutaneous squamous cell carcinoma of the skin with a differential diagnosis of a invasive lesion (cutaneous squamous cell carcinoma) and a non-invasive lesion (bowens disease or actinic keratosis). Exclusion Criteria: patients who waived informed consent
Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Non-invasive lesion<br>Lesion with histological confirmation of a actinic keratosis or Bowens disease (non-invasive lesions). | Diagnostic Test: Optical Coherence Tomography<br>* Assessment of the lesion with a non-invasive OCT scan according to a confidence scale (5-point Likert scale: 1 Definitely not invasive, 2 Probably not invasive, 3 Unknown invasive or non-invasive, 4 Probably invasive, 5 Definitely invasive)<br>* Other names: OCT;Other: Clinical assessment<br>* Clinical assessment of the lesion by a dermatologist according to a confidence scale (5-point Likert scale: 1 Definitely not invasive, 2 Probably not invasive, 3 Unknown invasive or non-invasive, 4 Probably invasive, 5 Definitely invasive)<br>|
| Invasive lesion<br>Lesion with histological confirmation of a squamous cell carcinoma (invasive lesions). | Diagnostic Test: Optical Coherence Tomography<br>* Assessment of the lesion with a non-invasive OCT scan according to a confidence scale (5-point Likert scale: 1 Definitely not invasive, 2 Probably not invasive, 3 Unknown invasive or non-invasive, 4 Probably invasive, 5 Definitely invasive)<br>* Other names: OCT;Other: Clinical assessment<br>* Clinical assessment of the lesion by a dermatologist according to a confidence scale (5-point Likert scale: 1 Definitely not invasive, 2 Probably not invasive, 3 Unknown invasive or non-invasive, 4 Probably invasive, 5 Definitely invasive)<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Sensitivity | Sensitivity of OCT to detect invasion | Through study completion, an average of 6 months | 
| Specificity | Specificity of OCT in determining the presence/absence of invasion | Through study completion, an average of 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Negative predictive value | Negative predictive value of OCT in determining the presence/absence of invasion | Through study completion, an average of 6 months | 
| Positive predictive value | Positive predictive value of OCT in determining the presence/absence of invasion | Through study completion, an average of 6 months | 
| Area under the curve | Area under the curve for OCT in determining the presence/absence of invasion | Through study completion, an average of 6 months | 
| Sensitivity of OCT features | Sensitivity for specific OCT-features characteristic for the presence/absence of invasion, such as presence/absence of the dermo-epidermal junction or presence/absence of hyperkeratosis. | Through study completion, an average of 6 months | 
| Difference OCT and clinical practice | Difference in diagnostic parameters (sensitivity, specificity and area under the curve) between OCT and clinical practice (clinical assessment). | Through study completion, an average of 6 months | 
| Specificity of OCT features | Specificity for specific OCT-features characteristic for the presence/absence of invasion, such as presence/absence of the dermo-epidermal junction or presence/absence of hyperkeratosis. | Through study completion, an average of 6 months | 
| Positive predictive value of OCT features | Positive predictive value for specific OCT-features characteristic for the presence/absence of invasion, such as presence/absence of the dermo-epidermal junction or presence/absence of hyperkeratosis. | Through study completion, an average of 6 months | 
| Negative predictive value of OCT features | Negative predictive value for specific OCT-features characteristic for the presence/absence of invasion, such as presence/absence of the dermo-epidermal junction or presence/absence of hyperkeratosis. | Through study completion, an average of 6 months | 
| Area under the curve for OCT features | Area under the curve for specific OCT-features characteristic for the presence/absence of invasion, such as presence/absence of the dermo-epidermal junction or presence/absence of hyperkeratosis. | Through study completion, an average of 6 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Optical coherence tomography, Invasion, Diagnostic device, Non-invasive