Ameloblastoma

CLINICAL NOTES:Pathology 

Lytic lesion in the mandible

MACROSCOPIC DESCRIPTION:

"L soft tissue ameloblastoma": An unorientated roughly ovoid piece of rubbery tan and yellow tissue 40x32x24mm. Surface inked all black. Slicing reveals a well demarcated rubbery cream-white mass 12x10x10mm, containing multiple cysts up to 3mm. The mass is 1mm from the resection margin. Adjacent to the mass is a well demarcated rubbery tan lymph node up to 12mm. The remaining tissue contains unremarkable lobulated yellow fatty tissue. Mass all submitted. P3. (SEK)

MICROSCOPIC DESCRIPTION:

Sections show fibroadipose tissue with two lymph nodes. One lymph node contains a 12mm maximum dimension well demarcated tumour comprising nests and anastomosing islands of columnar cells within a fibrotic stroma. There is peripheral palisading of columnar cells with subnuclear vacuoles and reverse nuclear polarity. The centre of the nests contain stellate reticulum-like cells with frequent cyst formation. Significant nuclear atypia, mitoses and necrosis are not seen. Perineural invasion is not identified. The tumour is 0.9mm from the resection margin. The remaining lymph node is unremarkable.

DIAGNOSIS: Left soft tissue ameloblastoma: Metastatic ameloblastoma within within 1 of 2 lymph nodes; resection margins clear of tumour.

Lytic lesion seen in the mandible which could be a KCOT or an ameloblastoma. 

There is an expansile lytic lesion involving the left mandible, measured at approximately 34 x 16 x 32 mm. There is cortical destruction at the buccal surface. 37 and 38 are both absent. The lesion extends to the left mandibular canal. Artefacts from filling of 36 noted. Soft tissue component of the tumour is seen together with gas. The outer cortical margin of the left hemimandible is preserved. The upper aspect of the left mandibular ramus is intact. No other focal bony destructive lesion identified within the mandible. No significant abnormality is seen within the TM joints. Minimal mucosal thickening is seen in the right maxillary sinus base. Several shotty lymph nodes are evident within the neck, without significant lymphadenopathy.

CONCLUSION:

There is a focal bony expansile destructive lesion in the left hemimandible in keeping with aameloblastoma. or a KCOT.