Familial Nasopharyngeal Carcinoma 6

258 W. I. WeiTumourAdipose tissueFig. 20.6. Tumor infiltrating the soft tissue in the neck.(Haematoxylin and eosin × 150)TumourFig. 20.9. MRI scan showing the multiple lymph nodes haveinfiltrated the overlying sternomastoid muscle and the muscleof the floor of the posterior triangle (arrows)neck dissection. When a less-extensive salvage procedureis performed, then tumor cells might be leftbehind leading to failure of the salvage effort.FasciaFig. 20.7. Tumor infiltrating the fascia of the sternomastoidmuscle. (Haematoxylin and eosin × 150)NerveTumourFig. 20.8. Tumor lying close to the spinal accessory nerve.(Haematoxylin and eosin × 150)In view of the extensive infiltrative nature of theserecurrent or residual malignant cells in the cervicallymph nodes after radiation of chemoradiation, thesurgical salvage procedure should be at least a radical20.3.5Salvage of Extensive Neck RecurrenceSometimes the recurrent or residual disease mightbe extensive, lying close to or infiltrating the overlyingskin or muscle of the floor of the posterior triangle(Fig. 20.9). Occasionally, during the radicalneck dissection, the malignant lymph nodes could bemacroscopically dissected off vital structures in theneck, such as the vagus nerve, internal carotid artery,or brachial plexus, the resection margins would beclose. Further adjuvant therapeutic measures shouldbe instituted to eradicate the possible microscopicmalignant cells to ensure tumor clearance. As theneck of all these patients has been irradiated, furtherexternal radiation might lead to complications andwould not be advisable.After-loading brachytherapy to the surgical bed,however, could be considered when the clearanceof the deep surgical margin is dubious. During theradical neck dissection, the area where microscopicaltumor might be left behind is marked. Hollow nylontubes are placed on this area; the tubes are placed at aregular distance from one another (Fig. 20.10). Thisdistance depends on the radiation dosimeter of