Hello! My guinea pig is a 5-year-old girl. I am quite an amateur in dealing with guinea pigs, especially regarding vet visits as I have never been in a similar situation before. Recently, a lump appeared under her armpit. We have been already to the vet and on our first visit we were prescribed the antibiotics(Orniflox) and painkillers/anti-inflammatory medicine(Rheumocam) but the lump remained unchanged. Apart from that, the vet has also mentioned that they have discovered a solid body there. However, today we have been there once again and we were eventually given just 2 options: a high risk surgery or just leave it be. They are not able to identify the mass inside as when they tried to puncture it to get some samples, she started to bleed profusely. I am just at a loss. I don't know what would be better for her. At the moment, the lump does not impare her movement or causes pain as she is as active as she has been before and eats well. This is the vets verdict: "The mass is closely attached to the muscles of the inner arm and the armpit. Removing the mass is not easy. However, there are no good alternative treatments, as the mass is expected to continue growing and may eventually interfere with walking or lead to necrosis and, consequently, an open wound. The anesthesia risk is increased due to the animal's species, age, and the expected duration of the surgery. During postoperative care, there is a risk of wound infections and impaired healing due to the guinea pig's self-manipulation. The type of tumor can be determined through a histological examination if you wish. This would help assess the risk of metastases and recurrence." I am looking forward to hearing your advice. Thanks!