Can a vet's FNA test misdiagnose a pet's lump or cyst, and why?

Fine needle aspirates are just a screening tool. You are placing a very small gauge needle into a large lump of tissue so it is always possible that you are missing some cells that would be diagnostic. It is also possible to go through the mass and get cells that just surround it. An FNA can be helpful in screening but if it is not diagnostic, the next step is an actual biopsy or full removal of the mass with histopathology. I have seen you ask this question multiple times and I'm sorry but we are not going to be able to answer it without seeing the report. It sounds to me like he had reactive lymph nodes (lymphoid hyperplasia) and I would not be overly worried about it at this stage if he is doing better. If the lymph nodes swell up again then you should have one or both removed and the entire lymph node sent to the lab for a histopathology. That is the only way you are going to get an answer. This article may give you a better understanding. ( https://www.petmd.com/dog/conditions/cancer/c_multi_lymphadenopathy )

Poor Precious! I know you are worried about you! Good news is that most mast cell tumors are easily distinguished on an fine needle aspire (FNA). The chances of it being a mast cell tumor is less likely but not completely ruled out. Also, the fact that it hasn't grown much and the cells on the FNA were very similar in size and shape means it is likely benign. I think you are making the best decision to have it surgically removed and tested. Also, it is likely more oval due to some local inflammation secondary to the minor trauma a FNA causes. I hope this helps!

Thanks for using Petco Pet Education Center, formerly Petcoach! This could be a benign or malignant growth. This is often differentiated by a test called a fine needle aspirate (FNA) which is a pain free, inexpensive and easy procedure which in most cases will help reach a diagnosis. This may be enough to diagnose her growth. Sometimes a biopsy is needed for a definitive diagnosis. I recommend that you have her evaluated by your veterinarian for further assessment and treatment. I am really hoping for something benign. Good luck and have a good day!

Hello and welcome to Petco Pet Education Center, formerly Petcoach. I am sorry that Max has a lump. FNA (Fine needle aspirate) is the name of the procedure your vet performed. Some types of cancers, including Mast Cell Tumors, will exfoliate (give off) a lot of cells when this procedure is performed, and have a very classic appearance under the microscope. Therefore yes, this is a proper procedure and diagnostic test. I would recommend that you chat with your vet about staging (looking to see if the cancer has spread to other locations of the body- usually using ultrasound and chest x-rays), and if it has not, have the tumor removed. Ensure you chat with your vet about if they are comfortable doing the surgery to get proper margins (3cm diameter and 3 facial planes) or if a surgical specialist is required. This will depend on the location of the mass. Best of luck with Max, hopefully it is a low grade and will be cured with surgery!

Thanks for using Petco Pet Education Center, formerly Petcoach! These could be benign or malignant growths. This is often differentiated by a test called a fine needle aspirate (FNA) which is a pain free, inexpensive and easy procedure which in most cases will help reach a diagnosis. Sometimes a biopsy is needed for a definitive diagnosis. I recommend that you have him evaluated by your veterinarian for further assessment and treatment. I am really hoping for something benign. Good luck and have a good day!

Thanks for using Petco Pet Education Center, formerly Petcoach! These could be benign or malignant growths. Since these have remained present, it would be best to have them evaluated. There is no way of knowing what it is just based on its appearance. This is often differentiated by a test called a fine needle aspirate (FNA) which is a pain free, inexpensive and easy procedure which in most cases will help reach a diagnosis. Sometimes a biopsy is needed for a definitive diagnosis. I recommend that you have her evaluated by your veterinarian for further assessment and treatment. I am really hoping for something benign. Good luck and have a good day!

Thanks for using Petco Pet Education Center, formerly Petcoach! These could be benign or malignant growths. There is no way of knowing what it is just based on its appearance. This is often differentiated by a test called a fine needle aspirate (FNA) which is a pain free, inexpensive and easy procedure which in most cases will help reach a diagnosis. Sometimes a biopsy is needed for a definitive diagnosis. I recommend that you have him evaluated by your veterinarian for further assessment and treatment. I am really hoping for something benign. Good luck and have a good day!