PMC5772686_01
Oral findings at the initial examination: There is an ulcer adjacent to the right upper molar region.
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A mobile lymph node measuring 1.5 cm was palpable in the right cervical region (Fig. 1).
(A) Contrast CT (initial scan): The posterior part of the right maxilla is destroyed by tumor. The right LRPLN is enlarged and shows rim enhancement. (B) PET-CT finding: There is abnormal accumulation in the posterior part of the right maxilla and in the right LRPLN. (C) Contrast CT (initial scan): Metastasis to the right submandibular lymph nodes is observed. LRPLN, lateral retropharyngeal lymph node.
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Enlarged lymph nodes with rim enhancement were seen in the right submandibular, superior internal jugular vein, and LRPLN regions (Fig. 2).
Biopsy specimen (H&E staining). Well-differentiated squamous cell carcinoma. Magnification, x100. H&E, haematoxylin and eosin.
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Biopsy revealed squamous cell carcinoma and the diagnosis was upper gingival carcinoma T4aN2bM0: Stage IV A (Fig. 3).
Contrast CT (before and after chemotherapy). (A) At the initial examination, (B) after 1 course of chemotherapy, there was a reduction in tumor size and (C) After 3 courses of chemotherapy, there was tumor regrowth.
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Thus, the primary tumor and LRPLN responded to the first course, but regrowth of the LRPLN was observed after 3 courses (Fig. 4).
Surgical findings. (A) Intraoperative photograph (skin resection line). Partial resection of the right maxilla, bilateral modified radical neck dissection, right LRPLN dissection and reconstruction with a free skin flap were conducted. (B) Intraoperative photograph (right neck). The carotid sheath (common carotid artery and vagus nerve) (arrow A) and sympathetic nerves (arrow B) are demonstrated. (C) Intraoperative photograph (right neck). LRPLN metastasis is seen (at the forceps tip). LRPLN, lateral retropharyngeal lymph node.
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Then the internal carotid artery, vagus nerve, and sympathetic nerves were dissected up to the base of the skull and fatty tissue was removed from the prevertebral fascia to complete dissection of the retropharyngeal space (Figs. 5 and 6).
Resected specimens. (A) Resected maxillary tissue. (B) Dissected neck tissue.
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Then the internal carotid artery, vagus nerve, and sympathetic nerves were dissected up to the base of the skull and fatty tissue was removed from the prevertebral fascia to complete dissection of the retropharyngeal space (Figs. 5 and 6).
Histopathological findings (H&E staining). (A) A section of the primary tumor (magnification, x40) shows fibrosis between bone tissues where the tumor may have been present. (B) Primary tumor (magnification, x200). Inflammatory cells (mainly lymphocytes) were observed at these sites, but no tumor cells were seen. (C) LRPLN (magnification, x40). Although fibrosis and cysts are present within the lymph node, proliferation of cancer cells is also observed. Part of the capsule is involved by the tumor. (D) LRPLN (magnification, x400). Tumor cells with enlarged, densely stained nuclei were observed, suggesting changes induced by chemotherapy (arrow). H&E, haematoxylin and eosin; LRPLN, lateral retropharyngeal lymph node.
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Tumor cells with enlarged, densely stained nuclei were observed, suggesting changes induced by chemotherapy (Fig. 7).