TOPLINE:

The European Association of Dermato-Oncology (EADO) classification system identified difficult-to-treat tumours in transplant patients with cutaneous squamous cell carcinoma (cSCC) on the basis of resectability, multiplicity, and spread, according to a retrospective analysis.

METHODOLOGY:

• Researchers conducted a retrospective analysis of 251 cases of invasive cSCC in 148 solid-organ transplant recipients at a single tertiary centre from 2010 to 2025, encompassing 742 patient-years.
• Overall, 94 difficult-to-treat tumours were found, which were distributed across five EADO groups: group 1 (65%), group 2 (10%), group 3 (3%), group 4 (16%), and group 5 (6%).
• Treatment strategies varied by group classification: Groups 1 and 2 received excision with complex reconstruction, group 3 underwent radiotherapy, group 4 received combined lymphadenectomy and radiotherapy with selective cemiplimab administration, and group 5 received systemic therapy.
• Difficult-to-treat cases were stratified using the EADO classification and cross matched with the American Joint Committee on Cancer (AJCC)-8 staging system.

TAKEAWAY:

• Most AJCC stage I tumours (108 out of 121; 89%) were easy to treat, with only a small subset requiring EADO classification as group 1 (n = 10) and group 2 (n = 3).
• AJCC stage II cases showed similar distribution, with 11 out of 15 (73%) cases classified as easy to treat and four cases falling into group 1.
• AJCC stage III cases had significantly increased complexity, with 47 tumours found in group 1, 38 being easy-to-treat cases, and smaller distributions observed in groups 2 (n = 6), 3 (n = 3), and 4 (n = 3).
• Nodal disease mapped predominantly to group 4, including all stage IVA and IVB cases, whereas metastatic disease stage IVC (n = 9) was split between groups 4 (n = 3) and 5 (n = 16).

IN PRACTICE:

"Using EADO alongside AJCC and BWH [Brigham and Women's Hospital] improves management of DTT [difficult-to-treat] cSCC by making difficulty explicit and linking anatomical stage to management pathways, thereby complementing anatomical staging and potentially broadening intralesional options in difficult disease," the authors wrote.

SOURCE:

This study was led by Javier Lara-Trigo, Department of Dermatology, Vall d'Hebron University Hospital, Barcelona, Spain. It was published online on January 27, 2026, in the Journal of the European Academy of Dermatology & Venereology.

LIMITATIONS:

Although case series described clinical benefit from conventional intralesional therapies and emerging treatments, evidence remained limited, necessitating dedicated trials to define optimal regimens that balanced tumour control with graft tolerance.

DISCLOSURES:

This study did not receive any funding. The authors reported having no relevant conflicts of interest.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.