Surgery for Squamous Cell Carcinoma of the Tongue and Floor of the Mouth

Auris·Nasus·Larynx (Tokyo) 12 (Supp!. II) S 5-S 9,1985

SURGERY FOR SQUAMOUS CELL CARCINOMA OF THE TONGUE AND FLOOR OF THE MOUTH Volker JAHNKE, M.D., F.A.C.S. Department of Otolaryngology, Rudolf- Virchow-Krankenhaus, Berlin, West Germany

Surgery for cancer of the tongue and floor of the mouth has become more varied and generally more conservative, influenced by advances in oncology and modern reconstructive methods. Combined therapy is favored, with postoperative irradiation and sometimes adjunctive chemotherapy, using cis-platinum. T] carcinomas of the tongue and floor of the mouth can be treated with either wide local excision or irradiation alone, but surgery is the preferred method. T 2T4 tumors treated by resection combined with radiation therapy promise the best results. The indications and principles of the most important operative procedures are discussed: local excision; partial and total glossectomy; excision of the floor of the mouth with marginal mandibular resection; composite resection. Mandible sparing operations such as a modification of the "pull through" technique described by Stell or temporary splitting of the mandible are oncologically safe in many cases. A radical neck dissection is indicated in each carcinoma of the tongue or floor of the mouth with palpable lymph nodes. If no nodes are palpable, an elective neck dissection appears justified in view of the high frequency of clinically occult lymph node metastases. Reconstructive measures following radical tongue and floor of the mouth operations are required for regaining mobility of the remaining tongue, for reconstruction of the floor of the mouth and for replacement of the mandible. For immediate reconstruction, the most frequently used technique is the pectoralis major myocutaneous flap which has largely replaced the previously employed local and regional flaps. A significant problem remains with mandibular reconstruction. The treatment of squamous cell carcinoma of the tongue and floor of the mouth has

changed over the past years as indicated by reports from this and other institutions (JAHNKE, 1975, 1978, 1983; BRADLEY and STELL 1982; CALLERY et al., 1984; SHAHA et al., 1984). Supported by knowledge in oncology, surgical procedures are more varied; generally they permit a better conservation of function and an improved quality of life by increased use of jaw-sparing operations and new techniques for reconstruction. Continuing efforts are made towards combined therapy with emphasis on postoperative irradiation and adjunctive use of chemotherapy in selected cases. Carcinomas of the oral part of the tongue and of the floor of the mouth are classified as oral cavity tumors, they are a clinical entity regarding their course and treatment. Our oncologic data show their highest incidence in the age group 50-60 years, with a male: female ratio of 70 : 30; the significant increase of female patients in the last 20 years is probably due to the increased intake of alcohol and tobacco. Carcinomas of the base of the tongue are part of the oropharynx and will not be discussed here; they differ from those of the oral tongue in their symptoms, therapy and prognosis. The basis for the choice of the proper treatment for carcinomas of the oral tongue and floor of the mouth is a classification according to the TN M system which has been proposed by the U ICC as indicated in Table I. The analysis of our own material showed that upon admission more than 50% of the carcinomas of the oral tongue and floor of the mouth were classified as T3 or

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Table 1. Carcinomas of the oral cavity (UICC classification). no palpable LN mobile ipsilateral LN mobile contra- or bilat. LN fixed LN

T2 2-4cm T3 > 4cm T, deep infiltra- Mo no evidence of distant tion metastasis M\ distant metastasis

T4 tumors. The most frequent localizations were the lateral margin of the middle one third of the tongue and the anterior part of the floor of the mouth respectively. Palpable neck nodes were found in more than :0% of the tongue lesions and in more than 75% of the floor of the mouth carcinomas: bilateral or contralateral metastases were not uncommon. However, the palpation is only of limited value, considering the frequcncy of microscopic metastases. Distant metastases were rare. The lymphatic drainage of the tongue and the floor of the mouth is mainly to the submental and submaxillary lymph nodes, further drainage is to the upper, middle and lower jugular lymph nodes. Important operative consequences result from the question whether lymph vessels pass through the periosteum of the lingual surface of the mandible. MARCHETTA et al. (1971) have shown. that involvement of the periosteum occurs histologically only as a result of direct extension even in large tumors with regional lymph node metastasis; it was not found when there was macroscopically still healthy tissue between tumor and mandible. More recently, however, it has been demonstrated that in dogs the lymph vessels do indeed penetrate the periosteum before they drain to the cervical lymph nodes so that the periosteum would not represent a barrier (OSSOFF et al., 1980). This paper is intended to discuss I. surgical techniques for removal of the primary and the indications for it ; 2. indications for neck dissection; 3. reconstructive aspects; 4. combined therapy. At present, the treatment for most carcinomas of the oral tongue and floor of the mouth is surgical, for many of them combined with postoperative irradiation. For a successful end result it is deci-

sive that the primary treatment is sufficiently radical and that therapy of the regional lymph nodes is an integral part of the treatment plan. Local removal only by elliptical longitudinal or transverse excision is restricted to tongue carcinomas of less than 1 em diameter. Particularly in the anterior one third of the tongue this is a safe method. A surrounding three-dimensional zone of 1-2 cm must be checked by frozen section. More problematic is the treatment of tongue carcinomas of 1-2 em diameter which are also Tl tumors. We do an excision of the primary with a wide safety margin as a peroral partial glosseetomy. Following anterior hemiglossectomy, the hemitongue advancement technique has been suggested (HOVEY, 1983): In order to avoid speech defects and salivary pooling due to a tongue that is too short or too narrow the median fibrous septum of the remaining tongue is divided and advanced forward to be sutured to the contralateral anterior one third of the tongue. Peroral resection of the floor of the mouth with concomitant marginal mandibulectomy is done for superficial Tl carcinomas of the floor of the mouth close to the mandible which otherwise could not be removed with a surrounding zone of 2 cm (DENECKE, 1980; JAHNKE, 1978). If no nodes are palpable, Tl tumors of the oral tongue and floor of the mouth may require only a unilateral functional ("conservative" or "prophylactic") neck dissection, though contralateral lymph nodes are frequently involved even in small carcinomas. Are nodes palpable, we prefer the resection of the primary in continuity with a radical neck dissection. The relatively poor cure rates of Tl tumors which according to the literatures are between 50% and 70% (JAHNKE, 1978; ApPLEBAUM et al., 1980; JOHNSON et al., 1980) are in favor of a more aggressive surgical therapy or postoperative irradiation. For carcinomas of the tongue and floor of the mouth of more than 2 em diameter the method of choice has been the composite or commando operation, i.e. the block resection

v. JAHNKE of the primary with ipsilateral segmental mandibulectomy and a radical neck dissection. This procedure corresponds well to the oncologic principle of combining the surgical removal of the primary with its actual or expected regional dissemination. The commando operation is always indicated in tongue and floor of the mouth carcinomas which are fixed to the mandible or to the inferiorly adjacent soft tissues, particularly in radiologically proven tumor infiltration of the mandible. In recent years, however, we favor a marginal mandibulectomy instead of the commando operation in many cases : The specimen is left attached to the submandibular region, the lower lip is split and a cheek flap raised as usual. With good access and vision, a marginal mandibulectomy is performed, preserving the base of the mandible without periosteum. For closure of the surgical defect a pectoralis major myocutaneous flap is usually used. This procedure appears oncologically safe in most tumors formerly treated by composite resection. The previous indication of facilitating the intraoral closure of the defect by composite resection is obsolete in view of the availability of reconstructive flaps. BRADLEY and STELL (1982) use a similar concept as a modified "pull through" resection without splitting the lower lip, excising the primary tumor in the mouth at the beginning of the operation. Treatment of the regional lymph nodes must be integrated in the concept of radical removal of the primary tumor. The indications for a neck dissection I have mentioned already. A radical neck dissection as a curative procedure is indicated for each tongue and floor of the mouth carcinoma with palpable regional lymph node:>. Usually it is performed as a block operation together with the removal of the primary tumor. If no nodes are palpable one has to consider the statistically high incidence of clinically occult lymph nodes; the range is from 17% to 43% according to the literature and was reported as 5% to 50% in a single study (TEICHGRAEBER and CLAIRMONT, 1984), depending

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on the stage of the lesion. The presence of cervical metastases is the single most important determinant for survival (LEIPZIG and HOKANSON, 1982; TEICHGRAEBER and CLAIRMONT, 1984) because the survival rate is reduced more by uncontrolled neck disease than by localized disease. Since the prognosis for delayed cervical metastases is poor and treatment of the clinically negative neck correlates with improved survival, an elective neck dissection must be considered in most tongue and floor of the mouth carcinomas without palpable lymph nodes; this is done either ipsilaterally, or-in view of the known lymphatic drainage-bilaterally as a functional ("conservative") neck dissection. An alternative would be elective irradiation. Though some authors question the value of elective treatment to the neck (PATTERSON et aI., 1984) we believe in a more aggressive therapy for the clinically negative neck in all of these carcinomas except 'for some well differentiated Tl tumors. For patients with unilaterally palpable lymph node:. a radical neck dissection of one side and a functional neck dissection of the other side is recommended. For bilaterally palpable nodes a bilateral radical neck dissection is indicated in an interval of about 6 weeks. In radical surgery for carcinomas of the tongue and floor of the mouth reconstructive procedures following the resection are supposed to provide a functional and cosmetic result which is acceptable for most patients. The goals are to regain a mobility of the remaining tongue, to reconstruct the floor of the mouth and to replace the mandible. For defects larger than those following a hemiglossectomy, or for deep defects of the floor of the mouth the pectoralis major myocutaneous flap is commonly used. It has largely replaced the previously employed local and regional flaps, i.e. the pedicled tongue flap, the horizontal forehead flap of McGregor and the deltopectoral flap of Bakamjian. The well vascularized pectoralis major myocutaneous flap is very reliable and practical; due to its volume it restores the contour of the defect very well and protects the

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carotid artery effectively, it allows primary closure of the donor site and requires only one stage. We always use a skin incision which permits a subsequent medially based deltopectoral flap if necessary. Disadvantages are the thickness of the skin-fat-muscle complex and the bulkiness of the muscle pedicle. The latissimus dorsi flap we suggest only if the pectoralis major myocutaneous flap cannot be employed; we do not have any experience with free flaps using microvascular anastomosis or with free jejunum grafts, both have their own morbidity and should be reserved for selected cases. Reconstruction of the mandible following radical surgery for carcinoma of the oral tongue and floor of the mouth is indicated both for cosmetic and functional reasons. There is still controversy regarding the necessity, timing, material and operative technique for such measures. Mandibular reconstruction is vital in anterior arch defects, but adequate primary resection can be usually accomplished here with preservation of mandibular continuity by leaving a rim of bone and using a pectoralis major myocutaneous flap for immediate reconstruction. Even after resection of the mentum this flap provides an excellent chin augmentation which mayor may not require stabilization by a subsequent bone implant. Autogenous, allogenous and alloplastic materials have been recommended for mandibular reconstruction and often pose serious problems. Graft failures are estimated as up to 50o/~, its largest causes being inadequate soft tissue replacement, infection and insufficient immobilization; delayed reconstruction is preferred for oncologic reasons and better results. Osteomyocutaneous flaps offer a therapeutic approach that may find wider use in the future. We continue to use planned postoperative radiation therapy to decrease locoregional failure and to increase survival. Combined chemotherapy with cis-platinum, bleomycin and methotrexate (JAHNKE, 1980) has been successfully employed as adjuvant and palliative treatment. The therapy discussed

here has reduced the morbidity and the need for mutilating surgery, offering adequate resection with a better conservation of function by immediate reconstructive methods. But the advanced clinical stage of carcinoma of the oral tongue and floor of the mouth and the poor results in the treatment have not changed significantly. In the literature, the 5-year-cure rate for all stages is reported between 22% and 66%. In our series it was less than 30%; of the advanced tumors on which we performed a subtotal or total glossectomy and in which the margins were tumor free histologically, nearly all died of their disease within 6 months to two years in spite of additional irradiation and chemotherapy (JAHNKE, 1977). Improved cure rates can only be expected by earlier treatment. References ApPLEBAUM, E.L., CALLINS, W.P., and BYTELL, D.E.: Carcinoma of the mouth. Arch. Otolaryngol. (Chicago) 106: 419--421, 1980. BRADLEY, P.J., and STELL, P.M.: A modification of the "pull through" technique of glossectomy. Clin. Otolaryngol. 7: 59-62, 1982. CALLERY, Ch.D., SPIRO, R.H., and STRONG, E.W.: Changing trends in the management of squamous carcinoma of the tongue. Am. J. Surg. 148: 449--454, 1984. DENECKE, H.J.: Die oto-rhino-laryngologischen Operationen im Mund- und Halsbereich. Springer Verlag, Berlin-Heidelberg-New York, 1980. HOVEY, L.M.: Hemitongue advancement following anterior hemiglossectomy, Plast. Reconstr. Surg. 71: 552-555, 1983. JAHNKE, V.: Die Chirurgie der Zungen- und Mundbodentumoren. Arch. Ohr- Nas- Kehlk-Heilk. 210: 275-288, 1975. JAHNKE, V.: Rekonstruktive Massnahmen in der Mundhohle und im Oropharynx nach Tumorresektionen. Laryngol. Rhinol. 0101. 56: 668675, 1977. JAHNKE, V.: Krankheiten der Zunge. Handbuch der Hals-Nasen-Ohrenheilk. Vol. III (Berendes, J., Link, R., and Zollner, F., eds.), pp. 7.1-7.45, Georg Thieme Verlag, Stuttgart, 1978. JAHNKE, V.: Erfahrungen mit dem neuen Zytostatikum Cisplatin bei PlattenepitheJcarcinomen im Kopf-Halsbereich. HNO 28: 405--408, 1980. JAHNKE, V.: Die Chirurgie der Zungenkorper- und Mundbodentumoren. Verh. Dtsch. KrebsGes. 4: 311-314, 1983.

V. JAHNKE JOHNSON, J.T., LEIPZIG, B., and CUMMINGS, e.W.: Management of Tl carcinoma of the anterior aspect of the tongue. Arch. Otolaryngol. (Chicago) 106: 249-251, 1980. LEIPZIG, B., and HOKANSON, J.A.: Treatment of cervical lymph nodes in carcinoma of the tongue. Head & Neck Surg. 5: 3-9, 1982. MARCHETTA, F.e., SAKO, K., and MURPHY, J.B.: The periosteum of the mandible and intraoral carcinoma. Am. J. Surg. 122: 711-713, 1971. OSSOFF, R.H., BYTELL, D.E., HAST, M.H., and SISSON, G.A.: Lymphatics of the floor of the mouth and periosteum: anatomic studies with possible

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clinical correlations. Otolaryngol. Head & Neck Surg. 88: 652-657, 1980. PATTERSON, H.e., DOBIE, R.A., and CUMMINGS, e.M.: Treatment of the clinically negative neck in floor of the mouth carcinoma. Laryngoscope 94: 820824, 1984. SHAHA, A.R., SPIRO, R.H., SHAH, J.P., and STRONG, E.W.: Squamous carcinoma of the floor of the mouth. Am. J. Surg. 148: 455-459, 1984. TEICHGRAEBER, J.F., and CLAIRMONT, A.A.: The incidence of occult metastases for cancer of the oral tongue and floor of the mouth: Treatment rationale, Head & Neck Surg. 7: 15-21, 1984.