Atypical case of primary intraosseous adenoid cystic carcinoma of mandible
A 64-year-old male patient reported to the outpatient department with the chief complaint of pain in the lower jaw. There was history of pain since five months, which was resistant to analgesics. Clinical examination revealed a slight, diffuse swelling throughout the buccal aspect of mandible. Gingiva appeared inflamed due to chronic generalized periodontitis with no other evident change in the mucosa. Submandibular lymph nodes were palpable but non-tender. Panoramic radiograph [] and intraoral periapical radiographs showed an irregular lytic lesion involving almost whole of the mandible. All teeth were vital.\nThe possibility of a malignant tumor was considered based on the clinical findings. On performing incisional biopsy, histopathological findings showed predominantly solid, tubular and cribriform pattern in very few areas. The tumor cells were basaloid in nature with scanty cytoplasm and oval to round nucleus. Peri-neural invasion was seen; and surrounding stroma was dense. Majority of the areas (>30%) showed solid pattern, hence the diagnosis of solid adenoid cystic carcinoma was made. To rule out the possibility of local and distant metastasis, subsequent examination including ultrasound scanning (USG), computed tomography (CT), chest radiograph and bone scan was advised. Distant metastasis was ruled out with no other lesions of the major or minor salivary glands.\nConsidering the size and bilateral extension of tumor, subtotal mandibulectomy (sparing the condylar stumps) along with bilateral suprahyoid neck dissection was planned as tumors >4 cm have been associated with an unfavorable outcome.[] Due to its peculiar clinical presentation, adequate soft tissue margin was removed prophylactically on both buccal and lingual aspect of the lesion. Sublingual and submandibular salivary glands were also removed bilaterally. Stabilization was done using 2.7 mm titanium reconstruction plate.\nHistopathology of the excised specimen showed intraosseous involvement of solid variant of adenoid cystic carcinoma [Figures and ], lymph nodes and excised salivary glands were negative. A final diagnosis of solid intraosseous ACC was given. Postoperative radiotherapy was given. Follow-up after 15 months since the initial diagnosis showed no sign of recurrence.