There are approximately 4,300 cases of lip cancer resulting in 100 to 150 deaths per year in the United States. Cancer of the lip is the most frequent site for cancer of the oral cavity. If treated early, the prognosis is excellent. There are, however, several prognostic indicators which may herald an aggressive disease and a poor outcome.
The incidence of lip cancer in the United States is 1.8 per 100,000. Patients typically present in their 7th or 8th decade. All reported series demonstrate that the disease occurs more frequently in males. The male to female ratio approaches 79-to-1 for cancer of the lower lip and 5-to-1 for the upper lip.
Several factors have been implicated in the etiology of lip cancer. Sunlight has been implicated as a major contributor to the development of lip cancer. Since the lip lacks a pigmented layer for protection, it is susceptible to actinic changes. Moderate to heavy cigarette and pipe smoking also play a causative role. In earlier studies, an association of carcinoma of the lip and positive serology or clinical evidence of syphilis was implied to be as high as 20%. More recent papers report not more than a 2% association. Poor oral hygiene results in persistent irritation and possibly lip cancer. Chronic alcoholism has been associated with the development of carcinoma of the lip as well as other sites in the oral cavity.
The most frequent location of lip cancer is the lower lip where it is reported being found between 91.3% and 97.3%. The upper lip is involved between 1.8% and 7.7% of the time, while the commissure is involved in 1% to 2%.
Almost 95% of lip cancers are squamous cell carcinoma. They are most frequently well differentiated. Basal cell carcinoma may extend onto the labial surface. Basal cell carcinoma is twice as common on the upper lip and is the most frequently neoplasm in that location. Approximately 300 cases of salivary gland neoplasms of the lip have been reported. Of these, 17% were malignant. Sixty-one percent were of the upper lip and 39% were of the lower lip. Melanoma infrequently involves the lips.
Patients typically present after a somewhat protracted course. The lesion is typically a crusted ulceration which bleeds easily. Patients are frequently treated with several courses of antibiotics with marked improvement. The lesion only later develops into a palpable mass. Actinic change is visible not only on the lip, but on other exposed skin. Leukoplakia of the lips may be seen. Lymphadenopathy, if present, is more likely to be inflammatory than metastatic, but needs to be addressed anyway. Hypesthesia of the area may indicate the possibility of perineural invasion and is more frequently seen in edentulous patients.
The primary goal of treatment is eradication of the disease. In decreasing order of priority, the goals of therapy are: 1) preservation of oral competence; 2) preservation of an adequate buccal sulcus; 3) minimalization of the deformity; and 4) restoration of a cosmetically acceptable appearance. Primary surgical excision offers the advantage of eradication of disease, pathological survey of margins, and reconstruction of the defect in a single stage.
Excision of T1 and small T2 lesions with a 6 mm to 10 mm margin result in a defect less than one-half the length of the lip. Defects of one-half the length of either the upper or the lower lip can generally be closed primarily. Defects of the middle of the upper lip may require excision of perialar skin.
Reconstruction of defects between one-half and two-thirds of the lip's length generally require a lip augmentation procedure. The Abbe flap, a full thickness flap from the opposite lip which is pedicled at the vermillion border, may be used to reconstruct defects of either the upper or lower lip not involving the commissure. The Estlander flap is a similar full thickness flap from the opposite lip that is used to reconstruct defects involving their commissure. The Karapandzic flap may also be used in such cases and has the advantage of being a vascularized, innervated myocutaneous advancement flap.
Reconstruction of defects greater than two-thirds of either the upper or lower lip generally requires adjacent cheek tissue if available. Numerous cheek advancement flaps have been described. Nasolabial flaps may be employed, either unilaterally or bilaterally, for reconstruction of the entire length of the lip.
Resection of T4 lesions of the lip may result in the need for total lip reconstruction. Infiltrating lesions may additionally require resection of bone and adjacent soft tissue. When adjacent cheek tissue is inadequate, regional flaps are preferable to distal flaps. Since most patients with T4 primary lesions will receive radiation therapy, the reconstructive effort should be directed toward closing the defect, covering exposed bone, and achieving early wound healing. The forehead flap may be used for reconstruction. This may be used as a unilaterally based flap or as a bipedicaled or visor flap. Probably the most useful flap for oral stoma reconstruction is the pectoralis major myocutaneous flap. Advantages of this flap include its viability after a radical neck dissection and its bulk. Other flaps available for reconstruction of the anterior oral cavity include the trapezius myocutaneous flap, the deltopectoral flap, and the latissimus dorsi flap.
Overall, 5% to 15% of patients with lip cancer will present with regional metastasis. An additional 15% will subsequently develop nodal metastasis. The five-year survival of patients with lip carcinoma and confirmed regional metastasis approaches 50%. The literature suggests that the survival rate for treatment of the initial neck metastasis by elective neck dissection and for salvage for the subsequent development of neck nodes is essentially the same. Due to the fact that less than 10% of patients with T1 or T2 lip cancers develop neck metastasis, most authors do not feel that a neck dissection is empirically indicated. For T3 and T4 lesions with a clinically negative neck, a node sampling procedure should be performed for biopsy.
When the patient presents with lip carcinoma and clinically positive unilateral neck nodes, a radical neck dissection is indicated. For larger primaries, especially if they approach the midline, thought should be given to performing a contralateral node sampling procedure. Patients with confirmed regional metastasis should be treated postoperatively with radiotherapy.
The prognosis for lip cancer depends on the extent of disease at the time of presentation. The five-year cure rate for T1 and T2 lesions without cervical metastasis approaches 90% with either surgery or irradiation. For T3 and T4 lesions, the five-year survival falls to 60% and 40% respectively. If cervical disease is present, the five-year survival rate falls to 50%.
A review of the literature indicates several prognostic indicators for lip carcinoma. Carcinoma of the upper lip and commissure carry a worse prognosis and the five-year survival is 10% to 20% lower than the overall rate. Cervical metastasis, especially when large, bilateral, or fixed indicate a poor prognosis as does the presence of distant metastasis. Poorly differentiated squamous cell carcinoma, as well as melanoma carry a worse prognosis. Recurrent squamous cell carcinoma at the site of the primary carries a worse prognosis and may be an indication of an aggressive neoplasm. The presence of mandibular involvement drops the five-year survival rate to 30%.
Case Presentation
A 69-year-old white man had a history of resection and primary repair of a lower lip squamous cell carcinoma one year prior to present admission. On routine follow-up evaluation, punch biopsies confirmed a parietal scalp squamous cell carcinoma and right lower lip actinic keratosis with microinvasion. The patient has a 45-pack-per-year history of smoking, describes occasional alcohol intake, and claims to have worked outdoors for the majority of his life. He has chronic obstructive pulmonary disease but denies other significant medical disorders and reports no other history of malignancy. Physical examination is significant for a 1.5 X 1.7 cm left parietal scalp squamous carcinoma and diffuse mid-lower lip actinic changes extending from the vermillion onto the skin surface. There was no lymphadenopathy. The chest x-ray showed mild chronic obstructive pulmonary disease, and laboratory evaluations were within normal limits.
The patient was taken to the operating room where he underwent excision of the scalp cancer followed by split thickness skin graft. Multiple biopsies of the lower lip revealed actinic keratosis with squamous cell microinvasion. He therefore underwent an excision of the involved lower lip with lateral flap advancement for primary repair. All surgical margins were free of tumor and the repair resulted in a functionally acceptable microstomia. (Baylor College of Medicine)
