A case study performed at University College Hospital London has documented the successful use of Michelson Diagnostics' Vivosight OCT scanner for the in-vivo mapping of non-melanoma skin cancer.
The study has been published in the March 2011 issue of 'Photodiagnosis and Photodynamic Therapy'.
The key benefit of the photodynamic therapy (PDT) of non-melanoma skin cancers over conventional surgical excision is that it is non-invasive and therefore avoids surgery scars.
This is a major advantage for the patient, because this type of skin cancer frequently occurs on the face, where disfiguring scars are undesirable.
However, as no tissue is removed for analysis in the PDT procedure, it can be difficult for clinicians to be sure that they have successfully treated the tumour, and this has limited its clinical use.
The case study shows that the use of a new Vivosight laser scanner developed by Michelson Diagnostics, to image skin before, during and after PDT treatment, could solve this problem.
The case study was performed by Zaid Hamdoon and a team led by Colin Hopper at the Unit of Oral and Maxillofacial Surgery at University College Hospital London and was supported by the Killing Cancer charity.
The Vivosight scanner uses a laser imaging technique called optical coherence tomography (OCT).
This provides images of sub-surface tissue similar to ultrasound but at far higher resolution, enabling the clinician to see critical details of the skin epidermis and dermis in real time.
Michelson Diagnostics has already obtained CE Mark and Food and Drug Administration (FDA) clearance for clinical use of the scanner in Europe and the US, and it is being evaluated at cancer clinics in these areas.
According to the authors of the paper, for each clinically visible margin, the pattern of the damage and the degree of tumour extension were clearly identified.
'Some areas exhibited almost perfect co-registration between the visible margin and OCT scan in terms of evident histological damage.
'With the advent of new optical technologies such as OCT, we can now monitor lesions more precisely and accurately so obviating many of the previous shortcomings of PDT.
'To our knowledge, this case study reports the first application of OCT for the in-vivo imaging and mapping of non-melanoma skin cancer.
'Additionally, OCT may help clinicians to monitor the outcome after the treatment, improving their understanding of the technique and offering an indication of the possible result to the patients.
'By other innovative approaches such as the OCT-guided fine needle aspiration cytology of treated areas, we can now confirm the absence of cancer or necessitate further treatment without the need to ablate normal tissues,' they added.
Prof Colin Hopper, the principal investigator of the case study, said: 'This case study is part of a larger programme of groundbreaking research at our unit into using OCT imaging for the clinical benefit of cancer patients.
'As well as improving PDT, mapping skin-cancer lesions with OCT should improve the delivery of other treatments such as Mohs surgery.
'We are looking to integrate OCT into our routine clinical pathway,' he added.
