Histiocytic cells are cells of the immune system responsible for cleaning up the remains of dead cells.
These cells can degenerate and start to multiply uncontrollably, forming a tumour. Either a histiocytic sarcoma will occur in a single organ or spread over multiple organs. This tumour type is locally invasive and local spread to the draining lymph nodes is possible.
Both the local and dispersed form have the potential to behave very aggressively.
Histiocytic sarcomas usually occur in middle aged dogs or older, but can also occur at the age of 3.
This tumour type occurs more in Bernese Mountain Dog, Flat-coated retriever, Golden retriever, Labrador retriever, Rottweiler than other breeds.
The location near the joint is most commonly reported in Rottweilers and Flat-coated retrievers.
Depending on where the tumour is located, it can cause different symptoms.
For example, a tumour in/near the mouth can explain a decreased appetite or mouth bleeding and one in/near the intestines diarrhea. In general, nonspecific symptoms are present: lethargy, loss of appetite, weight loss.
One can also notice a growth, limping, coughing, vomiting and swollen lymph nodes.