Oral carcinoma cuniculatum, a rare variant of squamous cell carcinoma.

INTRODUCTION: Carcinoma cuniculatum (CC) is a rare variant of squamous cell carcinoma (SCC). Lack of awareness of this tumor and its difficult diagnosis delay management and complicate treatment. The aim of this study is to describe the clinical and histological features, predisposing factors, treatment and survival rate of oral carcinoma cuniculatum. MATERIAL & METHOD: All patients with histologically confirmed CC of the oral cavity treated between January 2013 and August 2022 in a specialized center were retrospectively included. Patients were identified using the database ADICAP ("Association pour le Développement de l'Informatique en Cytologie et Anatomie Pathologique"). Once identified, the charts were reviewed. RESULTS: Ten patients were included. CC lesions were mainly located in the mandibular or maxillary gingiva, while the 2 remaining lesions were located in the mobile tongue. The tumor showed local aggressiveness: mandibular or maxillary osteolysis was systematically found for gingival CC, while tongue lesions were classified cT3. Fifteen biopsies were performed in these 10 patients, histological diagnosis is difficult on a limited tissue sample. All patients underwent curative management with oncological excision surgery combined with neck lymph node dissection, and adjuvant radiotherapy (except one patient). DISCUSSION: The main problem is the difficulty of diagnosis when biopsies are performed, which leads to a significant delay in diagnosis compared with SCC. In the event of clinico-histological discordance after biopsy, CC should be considered.

Contribution of FDG-PET in the diagnostic assessment of cervical lymph node metastasis in Oral Cavity Squamous Cell Carcinoma (OCSCC).

INTRODUCTION: The main objective of this study was to evaluate the contribution of FDG-PET in the diagnostic assessment of cervical lymph node metastasis in Oral Cavity Squamous Cell Carcinoma (OCSCC) and to advance a diagnostic threshold value for SUVmax in carcinomatous cervical lymph node. METHODS: 47 patients with OCSCC and suspicious cervical lymph node involvement (cN+) on FDG-PET were included in this retrospective study. The primary outcome was cervical lymph node SUVmax based on histological cervical metastatic disease (« gold standard ¼). RESULTS: Among the 77 cervical lymph nodes considered suspicious on patients' FDG-PET, 50 were really metastatic on histological examination. The lymph node SUVmax with metastatic involvement on histological examination was 4.6 ± 3.9 [2.6 - 23.7] versus 3.6 ± 1.2 [2 - 7.3] without carcinomatous involvement (p = 0.004). The lymph node size was not statistically significant according to metastatic disease (p = 0.28). DISCUSSION: A cervical lymph node SUVmax value of less than 2.6 on FDG-PET would suggest non-metastatic lymph node involvement. Supra Omohyoid Neck Dissection (SOHND) could therefore be performed in OCSCC when the SUVmax of the cervical lymph node is below this value in order to reduce the surgical morbidity of dissection of the lower internal jugular chain (Level IV).

In vivo evaluation of Adipose-Derived Stem Cells (ADSCs) using Nanofat technique and chitosan conduit for peripheral nerve defect repair.

INTRODUCTION: Nerve autograft is the gold standard for reconstruction of peripheral nerve loss. The alternative is the interposition of a synthetic regeneration conduit. The purpose of the study was to evaluate the in vivo feasibility and interest of Adipose-Derived Stem Cells (ADSCs) using the Nanofat technique and chitosan conduit for peripheral nerve defect repair. MATERIAL AND METHODS: In vivo, after the creation of a 10 mm defect of the sciatic nerve, 2 groups were defined according to the nerve repair in rats: "chitosan" group (n = 10) and "chitosan and ADSCs" group (n = 10) with a clinical and paraclinical evaluation at 7 weeks. RESULTS: The in vivo results seem to show that the adjunction of ADSCs was favorable clinically, histologically and functionally compare to a chitosan reconstruction alone. DISCUSSION: Peripheral nerve repair with defect using a chitosan conduit associated with ADSCs would constitute a surgical alternative in a single surgical step.