Differential Diagnosis for Canine Mass Rapidly Growing and Immobile
- Single most likely diagnosis
- Malignant tumor (e.g., mast cell tumor, soft tissue sarcoma): This is the most likely diagnosis due to the rapid growth and immobility of the mass, which are characteristic features of malignant tumors.
- Other Likely diagnoses
- Benign tumor (e.g., lipoma, histiocytoma): Although less likely than malignant tumors, benign tumors can also grow rapidly and become immobile.
- Infectious or inflammatory process (e.g., abscess, granuloma): These conditions can cause rapid growth and immobility of a mass, especially if they become chronic or are caused by a virulent organism.
- Cyst or hematoma: These can also present as rapidly growing, immobile masses, especially if they become large or infected.
- Do Not Miss diagnoses
- Aggressive malignant tumor (e.g., osteosarcoma, hemangiosarcoma): These tumors can be highly aggressive and have a poor prognosis if not diagnosed and treated promptly.
- Metastatic disease: If the mass is a metastasis from a distant primary tumor, it is crucial to identify the primary site to guide treatment and prognosis.
- Rare diagnoses
- Reactive histiocytosis: A rare condition characterized by the proliferation of histiocytes, which can form masses that grow rapidly.
- Mycobacterial or fungal infection: These infections can cause masses that grow rapidly and are immobile, especially in immunocompromised dogs.
- Foreign body reaction: A rare condition where a foreign body (e.g., a splinter) causes a localized reaction, leading to a rapidly growing, immobile mass.