General Medical Information

Lip Cancer Treatment

RAMON M. ESCLAMADO
CHARLES J. KRAUSE

The most efficacious treatment modality for lip carcinoma is one that allows adequate treatment of the primary tumor, management of cervical lymph nodes, and successful reconstruction.

Surgery and radiation therapy are equally effective in controlling early-stage lesions: 5-year determinate survival rates for lesions less than 3 cm average 90%. In several large series of patients treated with primary radiation therapy, the overall locoregional control rate was 85% to 93%, and the overall 5-year actuarial survival rate was 80% to 90%. Advanced tumors (T3 and T4) and clinically palpable nodes fared poorly, with 5-year actuarial survival rates of 40%.

A study comparing surgery versus radiotherapy concluded that cure rates are favorable with both modalities in stage 1 disease. Patients with larger tumors received radiotherapy more often and had a much poorer disease-free survival rate. Surgical management provides the opportunity to assess the thickness of the tumor and its histologic grade.

Radiation therapy is a low-risk noninvasive technique that avoids the potential complications associated with general anesthesia. However, the treatment time is prolonged (as much as 5 to 6 weeks), a whistle deformity may result from tissue loss and wound contracture with very large tumors, osteoradionecrosis of the mandible may develop, and future reconstructive options may be limited. Primary radiation therapy may be most useful in the treatment of early commissure lesions.

Surgical management is recommended for most patients. The surgeon can carefully control the tumor margins, rapid rehabilitation is possible with immediate reconstruction of the defect, and radiation complications are avoided. We prefer a combination of surgery and postoperative radiotherapy for stage III and IV disease and for recurrent disease after primary surgical treatment.

The standard approach to surgical resection of the primary lip lesion is full-thickness excision with 8- to 10-mm margins and careful intraoperative frozen-section evaluation of the surgical margins. The primary goal of therapy is eradication of all tumor tissue, without limitation for reconstructive considerations. Advanced tumors may require resection of chin skin, mandibular bone, or oral cavity soft tissues to allow a 2-cm margin. Skin incisions should be planned so as to minimize the secondary deformity and to facilitate reconstruction, but not at the expense of compromising tumor margins. The tendency to underestimate margins is more common in T2 lesions, where local recurrence rates have been higher than anticipated.

Vermilionectomy is indicated in superficial carcinoma limited to mucosa or multicentric or premalignant lesions. Recently, Mohs excision of lip carcinoma has been advocated, but this is primarily useful in stage I and II well-differentiated neoplasms that are 2.5 mm thick or less and have no muscle involvement. Recently, a metaanalysis of cutaneous squamous cell cancer that included the lip showed a 5-year local recurrence rate of 10.5% in 7,022 patients with standard surgical resection versus 2.3% of 952 patients undergoing Mohs micrographic surgery. However, this difference may be due to selection of less advanced lesions for Mohs surgery.

The management of regional lymph nodes in patients with lip carcinoma is controversial. In contrast to other squamous cell carcinomas of the oral cavity, lip carcinoma uncommonly metastasizes to regional lymph nodes. However, most mortality is due to uncontrolled disease in the neck. In several large series with 5-year follow-ups, the incidence of lymph node metastasis at the initial diagnosis ranged from 5% to 10%, and the rate of conversion from N0 to N+ in untreated necks ranged from 5% to 10%. The risk of nodal metastasis is directly related to the size of the primary lip tumor. The approximate incidence of clinically palpable nodes is 5% for T1 lesions, 5% to 10% for T2 lesions, and 67% for T3 and T4 lesions. Other large series report cervical node metastasis occurring in 4% to 7% of T1 lesions versus 16% to 20% of T2 to T4 lesions. This difference may be attributed to grouping T3 to T4 lesions with T2 lesions, which occur more frequently and have a lower metastatic risk, thereby lowering the overall risk of the entire group. Squamous cell carcinoma of the upper lip has a slightly higher rate of lymph node metastasis, and recurrent primary lesions develop delayed nodal metastases in about 26% of cases.

Several neck management strategies have been discussed in the literature. Our general approach to managing the cervical nodes is that patients with clinically palpable level I nodal disease undergo selective neck dissection removing nodal levels I to IV. Radical neck dissection or modified radical neck dissection with excision of the primary tumor may be performed when nodal disease involves nodal levels II to V. If nodal involvement is bilateral, the internal jugular vein is preserved on the less involved side if it is staged N1. If both necks are N2 or N3 and involve levels II to IV, consideration is given to staged radical or modified radical neck dissections 3 weeks apart. The facial arteries should be preserved unless involved with metastatic disease, but care should be taken to dissect the perifacial nodes.

For N0 necks, elective neck dissection is rarely indicated except in large recurrent lesions. Staging suprahyoid neck dissection is indicated in N0 necks when a significant risk (about 30%) of occult metastasis is present. Indications include large T2 lesions (3 to 4 cm) with N0 necks; recurrent disease at the primary site; or when ipsilateral N1 disease is present, the contralateral neck is N0, and postoperative radiation therapy is not planned. Indications for postoperative radiation therapy include a T3 or T4 primary tumor, a recurrent tumor, pathologically confirmed nodal metastases, extracapsular spread, or perineural invasion.