Experts in the non-invasive method for basal cell carcinoma (BCC) diagnosis known as optical coherence tomography (OCT) can succeed in improving the diagnostic abilities of novice assessors through supervision, according to recent findings.¹

BCC is known to be the most common form skin cancer, and the condition makes up over half of all non-melanoma skin cancers. It is known to affect around over 3 million Americans every year.²

These recent findings were the results of a study assessing to what extent a distant OCT expert may have been able to improve the diagnostic performance of a novice OCT assessor.³

The research was carried out as part of a broader assessment of whether or not OCT may be able to replace the standard biopsy procedure and, as a result, allow clinicians to diagnose and initiate treatment within the same patient consultation.

The work was authored by Tom Wolswijk, MD, MSc, from the Department of Dermatology at the Maastricht University Medical Center in the Netherlands.

“This study aimed to evaluate to what extent a distant OCT expert, who cannot directly inspect the patient, could improve the diagnostic performance of a novice OCT assessor,” Wolswijk and colleagues wrote.

Background and Findings

The investigators conducted their cohort study and recruited patients who had been suspected of having non-melanoma skin cancer underwent an OCT scan (Vivosight Multi-beam Swept-Source Frequency Domain) followed up with a biopsy.

The biopsy was used as a gold standard for histopathological examination, and the research team’s overall goal was to determine the diagnostic parameters for a high confidence OCT diagnosis. Additionally, they sought to compare the diagnostic abilities of a novice OCT assessor and an expert OCT assessor who was not on site.

The novice OCT assessor was trained with cumulative sum analysis and then evaluated OCT scans along with visual inspection of the suspected lesions.

The study assumed that OCT can only replace a biopsy if there is high confidence in the presence of BCC and its subtype. Otherwise, patients would undergo a biopsy to establish a final diagnosis and treatment regimen.

The study involved an assessment of 287 lesions, and 56.8% of them were found to be diagnosed as BCC. Both novice and expert assessors had a specificity of 96% for non-BCC detection using OCT.

The sensitivity of BCC detection was found by the investigators to be substantially higher for the OCT expert compared to the novice assessor (82.2% versus 71.8%, respectively). Similarly, the sensitivity for non-superficial detection of BCC—which required excision—was substantially higher for the OCT expert than for the novice (97.6% versus 89.2%, respectively).

The research team found that novice assessors reported a high specificity which suggests that there was a low risk of misidentifying non-BCC lesions as BCC.

“A limitation of this study is that the results are based on data from only 1 novice and expert assessor,” they wrote. “However, the results indicate that a novice assessor can achieve a high ability to discriminate BCC from non-BCC, and that supervision by an OCT expert can lead to detection of a higher proportion of BCC lesions and better discrimination between BCC subtypes.”

References

1. ^{Wolswijk T, Adan F, Nelemans P, et al. A cohort study on detection and subtyping of basal cell carcinoma with optical coherence tomography: The additional value of distant diagnosis by an expert. Journal of the American Academy of Dermatology. October 10 2022. https://doi.org/10.1016/j.jaad.2022.10.006.}
2. ^{American Academy of Dermatology. Basal Cell Carcinoma: Guidelines of Care for the Management of Basal Cell Carcinoma. https://www.aad.org/member/clinical-quality/guidelines/bcc. Accessed April 23, 2023.}
3. ^{Adan F, Nelemans PJ, Essers BAB, et al. Optical coherence tomography versus punch biopsy for diagnosis of basal cell carcinoma: a multicentre, randomised, non-inferiority trial. Lancet Oncol. 2022; 23: 1087-1096.}