Scientific highlights: Day 4
Dermoscopy and confocal microscopy cases 1
basal cell carcinoma (dermoscopy, OCT and confocal), squamous cell carcinoma (Bowen), melanoma vs nevus | Mariano SUPPA (Belgium)
Dr. Mariano SUPPA held a final conference as part of a session on dermoscopy and confocal microscopy. He offered an overview of the available techniques.
For instance, dermocopy eases the visualization of structures not visible to the naked eye and permits histopathological correlates, because of magnification lens and polarized and non-polarized light.
The RCM (Reflectance Confocal Microscopy) allows the visualisation of cells within the skin (cellular resolution) to obtain horizontal sections of the skin.
The HD-OCT (High-Definition Optical Coherence Tomography) facilitates visualization of cells within the skin with horizontal and vertical plans in real time 3D imaging even if cellular resolution is slow. We can compare the technique to a marine sonar emitting an acoustic signal, with the difference that the HD-OCT technique uses a weak signal.
Dr. SUPPA also discussed the LC-OCT technique that was the subject of another conference he held the day before. He proposed some applications to demonstrate the added value of this technique. With a general examination of the skin, it is sometimes difficult to immediately pronounce a diagnosis. The LC-OCT technique allows to immediately specify / confirm / cancel certain diagnoses, with a non-invasive examination. The speaker demonstrated how the technique assisted him to identify BCC difficult to diagnose with a single external examination, or how it helps him to distinguish glomerular vessels.
Cases: management of difficult to treat carcinomas
Advanced SCC arising in hidradenitis suppurativa | Eve MAUBEC (France)
Prof. Eve MAUBEC addressed the advanced SCC arising in hidradenitis suppurativa, which is a chronic suppurative and cicatricial disease, whose overall prevalence of 1% is doubled or even tripled in women. However, SCC transformations are predominant in men. This leads to long-term ulcers, fistulas and important scars. Squamous cell carcinoma resulting from HS is relatively rare with only 80 listed cases. The average age was about 52 years with an average HS duration of 25 before the diagnosis of SCC. For many of the observed cases, SCC was localized in perianal / perineal and gluteal regions. Only two associated risk factors were identified : HPV and smoking.
In terms of treatment, a robust response has been observed with PD1 inhibitors. Other promising inhibitors are currently being studied (pembrolizumab and nivolumab). It remains to be determined whether the anti-PD-1 activity is comparable or not in the SCC appearing in the hidradenitis suppurative compared to SCC exposed to the sun.
Keynote lectures 4
What's new in cutaneous lymphoma? | Marie BEYLOT-BARRY (France)
Pr. Marie BEYLOT-BARRY held the last conference of EADO 2019 congress addressing skin lymphomas, some of which are aggressive and represent a major challenge.
Despite the similarity of cutaneous lymphomas, very different behaviors are observed. A new classification of the EORTC group had a significant impact on the prognosis as well as on the therapeutic choices. This classification has been completed and incorporated into the classification of cutaneous lymphomas. Two new staging systems have been developed. The first objective was to distinguish indolent lymphomas from severe lymphomas.
The majority (80%) of indolent lymphomas do not require aggressive treatment. Complete remission is possible but minimal residual disease must be accepted. In case of recidivism, there is no aggressive MF. For Pr. BEYLOT-BARRY, it is necessary to limit the treatments (to adapt them and to re-evaluate them if resistance or progression), to improve the symptoms for the patient and to take more into account their quality of life.
For aggressive lymphomas, new therapeutic solutions are emerging. Systemic chemotherapy should be avoided to favor other treatments taking into account the risk of infection, the convenience of administration, etc.
The most encouraging results were obtained with allogeneic SCT treatment, the healing potential of which was unique for advanced FM / SS.
Histone deacetylase inhibitors (HDAC) modulate epigenetics by restoring the expression of tumor suppressor and / or cell cycle regulatory genes.
Targeted therapies such as brentuximab vedotin (an antibody-drug conjugate) selectively deliver a disruptive toxic microtubule into CD30-expressing cells. This induces an objective overall reaction of cell cycle arrest and apoptosis for at least four months.
Finally, immunotherapeutic treatments inhibit checkpoints. PD1 and PDL1 play a vital role in the ability of tumor cells to escape antitumor immunity. Another protein is in the limelight: MYD88, which activates when mutated (thus promoting cell survival).
For Pr. BEYLOT-BARRY, it remains to be determined how to predict progression and response to treatment, how to adapt a treatment to a specific patient, and especially to identify prognostic biomarkers.