Growth on anus -

9 year old Weimaraner/Lab Mix, around 55-60 lbs. Onset of sxs was around 3-4 months ago, starting as a small bump on his anus. This was the only sxs. Eating and drinking fine, no N/V/D. After a bit we noticed he seemed to have lost some weight, he was previously overweight (90lbs), but we attributed it to the fact that we recently moved to a 3rd floor apartment, and maybe the exercise was the reason. The growth seemed to increase in size pretty quickly, as it has been as pictured below for around a month or so. He is still eating and drinking normally. Food is his favorite thing in the world and his favorite hobby is begging. He doesn’t appear to have any pain. Other than from the significant weight loss, he doesn’t appear to have any other sxs. I know typically they would need to do a needle aspiration to get official dx but looking for an idea of what the possibilities are. Also attached a photo for an idea of his current size. Thank you!          

Hello and thankyou for this question; Im sorry that your loved one is struggling.  Significant weight-loss in the face of a good appetite could suggest any of a number of significant problems including cancer, diabetes (often with excessive drinking) and other endocrine conditions or liver disease.  A veterinary appointment sounds to be a priority and it's worth describing the symptoms in the terms I just gave, because this may be triaged as higher priority. For me, this is the most concerning symptom.  Lumps can be more benign - but may also be implicated. I hope that something here proves useful.  

Hello and thankyou for this question; Im sorry that your loved one is struggling.  Significant weight-loss in the face of a good appetite could suggest any of a number of significant problems including cancer, diabetes (often with excessive drinking) and other endocrine conditions or liver disease.  A veterinary appointment sounds to be a priority and it's worth describing the symptoms in the terms I just gave, because this may be triaged as higher priority. For me, this is the most concerning symptom.  Lumps can be more benign - but may also be implicated. I hope that something here proves useful.