CASE 1616 Published on 31.03.2006

Reconstructive surgery in a patient with cancer of the mobile portion of the tongue

Section

Head & neck imaging

Case Type

Clinical Cases

Authors

Sigal R, Kolb F, Jaw J

Patient

37 years, male

Categories
No Area of Interest ; Imaging Technique CT, MR, CT, MR, CT
Clinical History
The patient had a history of alcohol and tobacco intoxication.
Imaging Findings
The patient had a history of alcohol and tobacco intoxication. A lesion of the mobile portion of the tongue was biopsied and was proved to be a squamous cell carcinoma. CT (Fig.1) and MR (Fig.2) investigations were performed to evaluate the extent of the disease and decide the appropriate therapeutic strategy. The patient was treated surgically (removal of the mobile portion of the tongue with reconstruction by using a latissimus flap) and underwent radiation therapy (70Gy). Six months after the treatment was over, a baseline imaging assessment was done using CT (Fig.3) and MR (Fig.4). Cine MR was also performed to evaluate the mobilty of the tongue (Fig.5). A comparison of the post-therapeutic aspect of the tongue at 1 month (Fig.6) and 6 months (Fig.7) showed a marked decrease of post-therapeutic edema. Eighteen months after the treatment, a relapse was evidenced (Fig. 8).
Discussion
In the treatment of an oral cavity cancer, the aims of reconstructive surgery are to restore oral competence and oral cavity functions (speech, mastication, deglutition and management of secretions) facilitating the patient's social adaptation; to protect the great vessels; and to restore the patient’s external appearance of the face and the neck (1,2). In the case of cancer of the mobile portion of the tongue, the type of coverage primarily depends on the extent of the defect, and can be achieved by using several techniques of soft-tissue repair: primary closure, skin grafting and flaps. The main classification of flaps stems from the fact that the vascularity is maintained (pedicled flap, such as the pectoralis major myocutaneous flap) or surgically re-established (free flap) (2). The basic concept of free flaps was to obtain a degree of freedom which is not achievable with pedicled flaps and therefore to overcome the inconvenience of having the pedicled flaps, which are adynamic, anesthetic,and often bulky. Free flap surgery is a time consuming procedure performed only by highly specialized surgeons, and is mainly used in three situations: when a primary reconstruction of the mandible is needed, when a thin, pliable, one-stage flap is needed, and when the hypopharynx is removed. The radial forearm flap (3) has gained the greatest importance in the reconstruction of a variety of head and neck defects. It is an extremely versatile fasciocutaneous flap deriving its blood supply from the branches of the radial artery. Radial bone is usually not harvested because this leads to a 20% rate of the occurrence of radial fracture. This flap provides a hairless cutaneous area of a sufficient dimension which has been used to reconstruct the tongue, the soft palate, the posterior pharyngeal wall and the hypopharynx. Flap necrosis and fistulas are reported in approximately 5% and 7% of flaps, respectively (3). At the donor site, the commonest complication is delayed wound healing. On imaging, it is possible most of the time to identify the type of flap (pedicled versus free flap), but it may be difficult to understand the exact surgical procedure. A knowledge of the surgical report helps to report on the images. Identification of the different types of tissue which compose a flap can be usually easily done on imaging (4). The fatty portion may correspond not only to subcutaneous dermal or mesenteric tissue, but also to fatty degeneration of atrophic muscles owing to denervation and a lack of muscle function. The intact muscular portion of the flap shows MR signal intensities and CT attenuation equal to that of a normal muscle. The recognition of the arterio-venous pedicle, either in the axial pedicled flap, or in the free flap is more dubious. In the post-treatment period, it is recommended to perform reference baseline scans in patients at risk for tumor relapse or when post-treatment edema or pain prevents a good physical examination from being done (4). Performing a baseline scan for every patient at risk is important because the patterns of post-treatment temporal changes are highly variable from one subject to another. The baseline study should be performed no sooner than three months after completion of all treatments, at a time when acute and subacute inflammatory changes should have disappeared, although in some patients, a stable post-operative appearance is not reached until 12–18 months after completion of the treatment. The imaging features of a relapse are similar to those found in primary malignancy: tumors are displayed as CT/MR enhancing focal masses, either solid or partly cystic (5). In practice, the comparison between successive examinations often provides the clue to diagnosis by showing either a new mass and/or an abnormal reappearance of contrast enhancement. A relapse may occur in lymph nodes, with or without relapse at the primary site. The metastatic nodes may show the same pattern as seen at the pretherapeutic stage. However, because of neck dissection and irradiation, lymph nodes tend to present as poorly marginated, heterogeneous masses and can be located in unusual positions (4). The functional evaluation of the deglutition after partial surgery is achieved clinically, and by requesting the patient to swallow small quantities of liquid or solid. If aspiration occurs, videography can be done. Cine MR, as performed in this case, is still in the experimental stages.
Differential Diagnosis List
Squamous cell carcinoma of the tongue.
Final Diagnosis
Squamous cell carcinoma of the tongue.
Case information
URL: https://eurorad.org/case/1616
DOI: 10.1594/EURORAD/CASE.1616
ISSN: 1563-4086