Essential Cases in Head and Neck Oncology. Группа авторов

There was one additional node with evidence of central necrosis in right level 1b. Both lymph nodes were less than 3 cm in size.

FIGURE 3.3 Intraoperative photo of the right oral cavity defect after surgical resection of the primary tumor.

Answer: In a patient undergoing maxillectomy, it is critical to consider the best way to rehabilitate the defect. Limited defects, especially those with no communication to the sinonasal cavity, may require no reconstruction or simple adjacent tissue closure. For more extensive defects entering the sinonasal cavity, it is necessary to address this defect to allow for functional speech and swallowing. In this patient, an excellent option would be rehabilitation with a maxillofacial prosthesis. To do this, the patient must have adequate mouth opening and manual dexterity to allow for placement and removal. Moreover, retention is significantly improved when the ipsilateral canine tooth is maintained to allow for an adequate fulcrum for stability. Other contraindications to obturator use are resection of the orbital floor (unless a separate orbital floor repair is also performed) or resection of the anterior (premaxilla) or lateral (zygoma) projecting elements. Resection of the pterygoid plates does not significantly impact whether or not appropriate obturation can be achieved.

      The patient's final pathology demonstrates a 3.2 cm primary tumor, resected closest margin is 4 mm, posteriorly. There was only minor bone erosion seen. The neck dissection specimen showed 5 out of 58 lymph nodes positive. The largest lymph node was 2.7 cm, and there was evidence of extracapsular spread.

       Question: What would be the recommended next step in this patient's management?

      Answer: This patient has pT2N3bM0, stage IVb disease based on the 8th Edition of the AJCC staging system. The presence of a close margin at the primary site would indicate the need to consider adjuvant radiation therapy. However, the presence of extracapsular spread of cervical lymph nodes (or the presence of a positive margin at the primary that cannot be re‐excised) is an indication for adjuvant chemoradiation therapy as this has been shown to improve overall survival and disease‐free survival. Since the posterior margin was close but clear, re‐excision would not be necessary. The patient will benefit from concurrent adjuvant chemoradiotherapy with platinum‐based agents.

      Key Points

       Evaluation of oral cavity cancer starts with a biopsy and typically a CT scan of the face and neck with IV contrast to assess the extent of the primary lesion and to evaluate for regional lymphadenopathy. An MRI may be indicated if there is concern for significant perineural invasion, deep tongue invasion, or extension near the orbit, skull base, or parapharyngeal space. The use of PET/CT should be in patients with stage III or IV disease.

       Management of tumors of the maxillary alveolus typically involves upfront surgery with removal of the primary tumor with clear surgical margins. A neck dissection should be performed for pathologic lymphadenopathy. For cN0 patients, elective neck dissection should be considered for advanced (T3 or T4) primary tumors as it may improve cancer control. more recent evidence suggests elective neck dissection in T2 tumors or consideration of sentinel node biopsy to determine the need for neck dissection.

       Adjuvant radiation therapy should be considered for advanced primary tumors, the presence of lymph node metastases, perineural invasion, lymphovascular invasion, or close surgical margins.

       Adjuvant chemoradiotherapy should be recommended in instances of positive surgical margins and/or the presence of extracapsular spread in cervical lymph nodes.

       In patients where a maxillectomy is considered, options for reconstruction include the use of a maxillofacial prosthesis or the use of a regional or free flap. If a maxillary obturator is planned, it is essential to have the patient see a maxillofacial prosthodontist soon after diagnosis to allow for a prosthesis to be made prior to the day of the resection.

       In instances when there is resection of the orbital floor or orbital exenteration, or when there will be inadequate remaining dentition to retain an obturator, reconstruction with free tissue transfer should be considered in suitable candidates.

CASE 4

      Alok Pathak

      History of Present Illness

      A 75‐year old man with a 35 pack‐year smoking history presents for evaluation of a sore in the left side of his mouth. He quit tobacco 30 years ago but continues to drink two to three alcoholic drinks every day. He had extractions of tooth #17 and #18 3 months ago. However, the extraction site has not healed since then.

      Physical Examination

Oral cavity examination demonstrates a 2.5 cm proliferative mass over the left retromolar trigone adherent to the underlying mandible with loss of sensation over the left chin (see Figure 4.1). There is also a palpable 2 cm mobile left submandibular lymph node.

FIGURE 4.1 This intraoral photograph shows the lesion of the patient's left retromolar trigone extending on the left mandible body.

       Question: What is the most likely clinical diagnosis?

      Answer: In view of progressive proliferative growth, with loss of sensation over the distribution of mental nerve with the risk factors of past tobacco use and current alcohol, the most likely diagnosis is SCC. In the presence of a gingival growth, tooth extraction should be avoided as it provides easy access to the mandible through the tooth socket.

      Management

       Question: What is the best way to achieve preoperative tissue diagnosis?

      Answer: Punch/incisional biopsy. Since the lesion is easily accessible in the oral cavity, transoral incisional biopsy in the clinic is the most appropriate and expeditious way to get a tissue diagnosis. Fine needle aspiration of the lymph node may also be performed. However, a negative cytology from the lymph node does not rule out malignancy. Any consideration of an open biopsy of the lymph node should be avoided as it can complicate further neck treatment.

       Question: What would be the most appropriate next step in the evaluation of this patient?

      Answer: Considering the extent of the symptoms, imaging is recommended. CT scan of the head and neck with contrast is the most appropriate first step. Mental paresthesia is an indicator of the involvement of the inferior alveolar nerve in the mandibular canal. CT scan with contrast is the most appropriate imaging modality to assess the extent of mandibular invasion and cervical lymphadenopathy. If proximal extension of the tumor along the mandibular nerve is a concern on CT scan, an MRI could be obtained. For advanced oral cavity cancer, distant imaging is recommended, in the form of a CT chest with contrast or PET/CT.

Contrast‐enhanced CT of the neck shows a 4.5 cm heterogeneous tumor centered in the left retromolar trigone with underlying osseous destruction through the inferior alveolar canal. The erosive component of the tumor crosses the midline at the mandibular symphysis (see Figure 4.2). There are multiple enlarged and round lymph nodes in the left neck, the largest measuring 3.1 cm in left level 1b.

      Chest CT does not