Sentinel lymph node biopsy in 33 non-melanoma skin cancers of the head and neck: A twelve-year experience with long-term follow-up

Management of Non-Melanoma Skin Cancer: Radiologists Challenging and Risk Assessment

Basal cell carcinoma, squamous cell carcinoma, and Merkel cell carcinoma are the three main types of nonmelanoma skin cancers and their rates of occurrence and mortality have been steadily rising over the past few decades. For radiologists, it is still difficult to treat patients with advanced nonmelanoma skin cancer. Nonmelanoma skin cancer patients would benefit greatly from an improved diagnostic imaging-based risk stratification and staging method that takes into account patient characteristics. The risk is especially elevated among those who previously received systemic treatment or phototherapy. Systemic treatments, including biologic therapies and methotrexate (MTX), are effective in managing immune-mediated diseases; however, they may increase susceptibility to NMSC due to immunosuppression or other factors. Risk stratification and staging tools are crucial in treatment planning and prognostic evaluation. PET/CT appears more sensitive and superior to CT and MRI for nodal and distant metastasis as well as in surveillance after surgery. The patient treatment response improved with advent and utilization of immunotherapy and different immune-specific criteria are established to standardized evaluation criteria of clinical trials but none of them have been utilized routinely with immunotherapy. The advent of immunotherapy has also arisen new critical issues for radiologists, such as atypical response pattern, pseudo-progression, as well as immune-related adverse events that require early identification to optimize and improve patient prognosis and management. It is important for radiologists to have knowledge of the radiologic features site of the tumor, clinical stage, histological subtype, and any high-risk features to assess immunotherapy treatment response and immune-related adverse events.

Sentinel lymph node biopsy in high-risk cutaneous squamous cell carcinoma of the head and neck: Systematic review and meta-analysis

The aim of our study was to better define the role of sentinel lymph node biopsy (SLNB) in high-risk cutaneous squamous cell carcinoma of the head and neck (cSCCHN). A systematic review and meta-analysis was performed according to the PRISMA statement. Seven-hundred and five patients were included from 20 studies. The pooled SLN identification rate was 98.8% (95%CI: 97.0-99.8). The median number of SLN excised was 3.6 (n = 371, 95%CI: 2.0-4.4). The pooled SLNB positive rate and cumulative regional recurrence rate (RRR) in negative SLNB were 5.6% (95%CI: 2.6-9.6) and 2.9% (95%CI: 0.5-7.2), respectively. The high SLN identification rate demonstrates SLNB feasibility in cSCCHN. The low SLNB positive rate and the relatively high RRR raise some doubts concerning its clinical utility. Further studies are mandatory to define predictors of lymph node metastases able to better select patients that may benefit from a SLNB.

[Sentinel lymph node biopsy in head and neck oncology]

Sentinel lymph node biopsy (SLNB) has been initially developed for melanoma and breast cancers. Its application in head and neck cancers is recent, probably due to the complexity of the lymphatic drainage, the proximity between the primary tumor and the lymph nodes and the critical anatomical structures (such as the facial nerve). In onco-dermatology, SLNB is validated in head and neck surgery for melanoma with Breslow thickness up to 1mm or ulceration, Merkel carcinoma and high-risk squamous cell carcinoma. Considering the malignancies of the upper aerodigestive tract, the feasibility and oncologic safety of SLNB are now established for T1-T2N0 oral and oropharyngeal squamous cell carcinomas. Thus, it could allow patients with negative sentinel nodes to avoid an unnecessary neck dissection, leading to a decrease of morbidity with an quality of life improvement. For some primary locations (e.g., anterior floor of the mouth) with high proximity between tumor and lymph nodes, it is recommended to remove the tumor before the SLNB so as to improve the detection. New techniques of detection are currently being developed with intra-operative procedures and new tracers (such as tilmanocept), leading to a better accuracy of detection and, probably, new indications.