Search

A case report is given of a very rare spontaneous mast cell tumor in the eyelid of the left eye of a female Wistar rat used in a long-term oral toxicity study. Metastasis of the tumor had occurred in the mandibular lymph nodes and in the liver. Clinically, the animal showed blepharospasm, dacryorrhoea, and exophthalmus. Hematologic findings included slight eosinophilia and a remarkable basophilia. At necropsy, a bilateral conjunctivitis was diagnosed and a tumorous mass was found in the left submandibular region. Histologically, the tumor was composed of round to polygonal cells with pale cytoplasm, containing abundant predominantly basophilic granules. The intracytoplasmatic granules stained metachromatically with Toluidine blue and immunostained positively with serotonin. Numerous eosinophils were scattered throughout the tumor and were also present in other organs. Cells with round, oval, or indented nuclei and abundant cytoplasm, containing pronounced eosinophilic granules, were found in spleen and bone marrow. They turned out to he immature stages of eosinophilic granulocytes. Characteristics of the present tumor are compared with observations on mast cell tumors in other species.

A case report is given of a very rare spontaneous mast cell tumor in the eyelid of the left eye of a female Wistar rat used in a long-term oral toxicity study. Metastasis of the tumor had occurred in the mandibular lymph nodes and in the liver. Clinically, the animal showed blepharospasm, dacryorrhoea, and exophthalmus. Hematologic findings included slight eosinophilia and a remarkable basophilia. At necropsy, a bilateral conjunctivitis was diagnosed and a tumorous mass was found in the left submandibular region. Histologically, the tumor was composed of round to polygonal cells with pale cytoplasm, containing abundant predominantly basophilic granules. The intracytoplasmatic granules stained metachromatically with Toluidine blue and immunostained positively with serotonin. Numerous eosinophils were scattered throughout the tumor and were also present in other organs. Cells with round, oval, or indented nuclei and abundant cytoplasm, containing pronounced eosinophilic granules, were found in spleen and bone marrow. They turned out to he immature stages of eosinophilic granulocytes. Characteristics of the present tumor are compared with observations on mast cell tumors in other species.

The palpebral region is one of the commonest locations for basal cell epitheliomas of the face. The tumor can spread to both orbital cavity and its structures. Ten patients with basal cell epitheliomas of the face were studied with US to investigate its diagnostic accuracy; US findings were compared with CT ones. In all cases US allowed a complete study of both morphology and structure of the tumor; it precisely defined the status of the superficial structures of the orbital cavity (cornea and anterior chamber of the eye), differentiating between tumor contiguity, compression and infiltration. US seems therefore essential to the preoperative assessment of tumor spread and during the follow-up of patients with palpebral basaliomas.