Skin Masses - Ferret
Introduction
The most common cause for a cutaneous mass in the ferret is neoplasia. Abscesses and enlarged lymph nodes are other common causes. All masses that are detected should be fully worked-up as this allows the immediate excision of any neoplastic mass. The 'wait-and-see' method should be avoided if possible as the most likely differential is neoplasia.
Differential Diagnoses
Neoplasia, abscesses and enlarged lymph nodes may produce a mass in or under the skin. The types of neoplasia that can occur are: mast cell tumor or mastocytoma, sebaceous gland adenoma and adenocarcinoma, benign cystic adenomas, fibroma and fibrosarcoma, hemangioma, cutaneous hemangiosarcoma, chordoma, neurofibroma, leiomyoma, histiocytoma, squamous cell carcinoma, basal cell carcinoma, cutaneous lymphoma and melanoma - the most common being benign mast cell tumours, sebaceous gland adenomas and haemangiomas.
Clinical Signs
The ferret may present with a mass palpable in or under the skin surface. If an abscess is present the ferret may be pyrexic.
Diagnosis & Treatment
Initially a fine needle aspirate should be taken of the mass to differentiate between the common causes of cutaneous masses. Treatment then depends on the diagnosis:
Neoplasia
Most ferret neoplasms are benign, but metastasis can occur. Therefore before the mass is excised screening should be performed to check for metastases. Radiography or ultrasound can be used to assess the lungs and liver for metastases and to check for involvement of underlying tissue involvement. If metastases are present then the next steps should be discussed with the owner as chemotherapy and radiotherapy are not successful in treating metastases in the ferret.
Following screening (assuming there is no metastasis), the mass should be completely surgically excised and sent for histopathological analysis. A diagnosis and prognosis can then be made based on the tumour type. If there is more than one mass present then all the masses should be sent for histopathology as the tumours may be of different types.
Abscess
The abscess should be suitable lanced and drained and the ferret treated with appropriate antibiotics.
Lymph Node Hyperplasia
If the mass is a reactive lymph node then the underlying cause for this should be identified and treated appropriately.
Prognosis
Prognosis is dependent on the diagnosis. If the mass is an abscess the prognosis is good with appropriate treatment. If the underlying cause for lymph node enlargement is identified and treated the prognosis is also good. In the cases of neoplasia, the tumour type, the speed of diagnosis and the presence of metastasis all determine the prognosis. As a general rule, any benign neoplasia that is completely surgically excised should have a good prognosis.
References
Bond, Hendricks, Loeffler (2009) Veterinary Dermatology RVC Intergrated BVetMed Course, Royal Veterinary College
Brown, SA & Rosenthal KL (1997) Self-Assessment Colour Review Small Mammals Manson Publishing Ltd