Squamous cell carcinomas are serious cancers, due to their local infiltration but also their possibility of metastasizing distantly. They represent 90% of oral cavity cancers [1]. The main risk factors for the occurrence of squamous cell carcinoma are alcohol and tobacco consumption. The combination of the 2 having a synergistic effect [2-4]. Other factors have been described: poor oral hygiene, viral infections (HPV), immunosuppression (HIV AIDS), certain genetic pathologies (xeroderma pigmentosum). Precancerous lesions are known: leukoplakia and erythroplasia. Leukoplakia is common but less likely to develop into squamous cell carcinoma. Erythroplasia is less common but at high risk of transformation into squamous cell carcinoma [5,6].

Lip cancer is a typical malignancy that accounts for 25-30% of all oral cancers [7]. Oral and lip cancer is a major global health problem [8]. The warning sign on the lip is generally an ulceration or a budding ulcerative lesion which justifies consultation [9]. The diagnosis is based on the histological analysis of a biopsy which confirms the diagnosis and specifies the histological subtype. A radiological assessment makes it possible to evaluate the loco-regional (CT or cervico-facial MRI) and distant (thoraco-abdomino-pelvic CT) extension in search of distant metastases [10,11]. At the end of this extension assessment, the patient is classified according to the TNM classification of the AJCC and UICC [12]. The treatment will depend on this classification, which will be discussed in a multidisciplinary consultation meeting in order to propose a personal treatment plan.

The majority of our patients were classified stage IV A. This is explained by the delay in consultation. The therapeutic protocol at this stage includes surgical resection of the tumor, cervical lymph node dissection, reconstruction of the defect and postoperative radiotherapy. Surgical resection requires safety margins of 1cm in order to be carcinological [13]. When the tumor infiltrates the underlying bony structures (mandible or maxilla), bone resection is necessary (non-interrupting or interrupting mandibular resection, maxillectomy) depending on the extent of the infiltration. We did not use the Mohs technique.

We used selective lymph node dissection involving lymph node areas I, II and III. Cervical lymphadenectomy in the form of elective neck dissection offers improved overall and disease-free survival compared with therapeutic neck dissection for the majority of oral cancers with recent evidence suggesting advantages even for tumors less than 4 mm in thickness [14]. We did not use the sentinel lymph node technique.

Reconstruction options include local flaps, regional pedicled flaps, and microvascular free tissue transfer [15]. Hard tissues can be reconstructed using free autologous bone grafts (iliac bone, fibula), but also involve the use of free tissue transfer from the iliac crest, fibula, radius or scapula.

Adjuvant radiotherapy improves local control and overall survival in advanced tumors. It should be considered in all patients with larger T3 or T4 tumors, or N2-3 neck disease. The morbidity of radiotherapy to the primary site of the oral cavity means that the benefits and side effects must be carefully considered for each patient.

The 5-year overall survival of squamous cell carcinoma of the lips is estimated at 40-50% [13].