Case Study

CT – Malignant sinus neoplasia with extensive bone destruction in a 8 year old FS Maltipoo

This 8 year old FS Maltipoo dog has a history of a hole in the head. Lytic lesion in sinus beginning to communicate with cranial cavity

DX

The computed tomographic findings are compatible with malignant neoplasia with extensive and highly aggressive bone destruction

Image Interpretation

CT of the head –

A significant asymmetric soft tissue swelling with a mass effect is seen on the dorsum of the nose and frontal bones. Both nasal passages and frontal sinuses are almost entirely obstructed by the soft tissue attenuating and non-uniformly enhancing mass. The frontal sinuses are occupied by the mass. There is extensive bilateral asymmetric destruction of the maxillary, nasal, frontal and parietal bones. Severe turbinate destruction and nasal septal lysis is seen as well as lysis of the cribriform plate creating an open connection to the cranial fossa and brain. Mild amounts of amorphous periosteal new bone are seen at the affected bones too. The soft tissue component of the mass penetrates the bony orbit and reveals subtle extension into the left and right retrobulbar region.

The medial retropharyngeal and submandibular lymph nodes present bilateral mild enlargement with mild rounding and non-uniform contrast enhancement pattern

Outcome

Squamous cell carcinoma, osteosarcoma, hemangiosarcoma, lymphosarcoma, fibrosarcoma, hemangiosarcoma, melanoma, esthesioneuroblastoma and mast cell tumor are possible differential diagnoses. There is bilateral involvement of the nose and frontal sinuses, the cranial fossa including a mass effect on the brain and both orbitae.
Metastatic spread to the regional lymph nodes is suspected.
The prognosis is poor.
Radiation therapy and/or chemotherapy might be considered as palliative measures.