I. Surgical treatment
Surgical resection and radiotherapy are still the two most effective methods to treat oral cancer, and the combination of the two is often better than alone. Chemotherapy is still an adjuvant treatment, which is used before surgery or in combination with radiotherapy. The choice of surgery and radiotherapy depends on the clinical experience and technology of the treating physician and the conditions and equipment of the hospital, in addition to the condition. A multidisciplinary consultation method should be used to decide the treatment plan by objectively estimating the patient’s condition. The success or failure of oral cancer treatment is largely determined by whether the first treatment is correct. Surgical treatment can be adopted if the following conditions are met.
1.No distant metastasis: the primary foci and cervical metastases can be removed within the safe boundary;
2.The lesion is poorly treated by radiotherapy;
3.The damage of oral function caused by surgical resection is not large, or although large, it can be compensated to a considerable extent through reconstruction or pseudo-recovery and the patient’s consent can be obtained.
Usually, patients with oral cancer rarely have distant metastasis when they first visit the clinic. If distant metastasis is suspected, especially when the primary cancer is small, the second primary cancer should be excluded first. Adenoid cystic carcinoma of the oral cavity can occur early with distant metastasis, but surgery can still be considered if this carcinoma has a long course and the primary site is still resectable.
Although CT can help to estimate the extent of cancer invasion, the extent of invasion can still be found to be larger than originally estimated at the time of surgery. This situation should be fully considered before surgery.
Even a small amount of cancerous tissue remaining in the surgical field that is visible to the naked eye will make surgical treatment unsuccessful or significantly reduce the treatment outcome. If the tumor is estimated to be completely removed but the safety boundary is not enough, surgery can be considered after preoperative radiotherapy and/or chemotherapy, or surgery followed by radiotherapy.
Radiation therapy
Radiation therapy plays an important role in the treatment of oral cancer, whether used alone or in combination with surgery. For early stage lesions, external irradiation with interstitial implantation can achieve the same effect as surgical resection, and can maintain cosmetic, normal chewing, swallowing and pronunciation functions, so as to improve patients’ quality of survival. For intermediate and advanced lesions, especially when cervical lymph node metastases are present, radiotherapy alone is less effective. The ideal treatment plan should be developed by radiologists and surgeons in cooperation with each other according to the anatomical location of the lesion, the extent of infiltration, the degree of cervical lymph node metastasis and the patient’s general condition.
1.External radiation therapy
It is suitable for those who cannot receive interstitial or surgical comprehensive treatment for various reasons, as well as those who have local recurrence or extensive lesions for palliative treatment after treatment.
2.Preoperative radiotherapy
The purpose is to control the primary foci or subclinical lesions in the lymph nodes of the neck, to reduce the chance of dissemination during surgery, and to reduce the size of the tumor, so that the original inoperable tumor lesions become operable, thus improving the surgical resection rate and reducing the local recurrence rate.
3.Post-operative radiotherapy
It is suitable for cases with residual cancer after surgery or pathological examination suggesting that there is cancerous tissue at the cut edge or the cut edge is less than 0.5cm from the edge of tumor tissue. Radiotherapy can be carried out after wound healing after surgery.
4.Interstitial radiotherapy
Radium needle interstitial radiotherapy has been widely used in clinical practice for half a century, and has achieved satisfactory local control effect on the treatment of tongue cancer, buccal mucosa cancer and floor of mouth cancer, etc.
Radium needle interstitial insertion therapy has been widely used in clinical practice for half a century and has achieved satisfactory local control effect on the treatment of tongue, buccal mucosa and floor of mouth cancers. With the emergence of artificial radioisotopes 192Ir, 125I, 198Au, etc. and the development of post-loading technology, radium needle treatment has been replaced by 192Ir post-loading interstitial therapy.
5.Oral cartridge irradiation
It is suitable for small lesions that are shallow, easy to expose, and can maintain the irradiation position, and the depth of cancer infiltration is less than 0.5 cm. as an additive irradiation technique before or after external irradiation, kilovoltage X-rays or electron beam irradiation is used to reduce the amount of jaw bone subjected to the dose and increase the dose in the tumor area to reduce late complications.