Brief Answer:
Needs confirmatory tests redone!

Detailed Answer:
Hi.
Thanks for your query and history.

Your contributing a bit more detailed history would help me:
-Since when the swelling is present?
-Is it a single node or a conglomeration of many?
-Was it painful / any redness of the skin / or clod meaning normal?
-Any other history like evening rise of temperature, loss of appetite, loss of weight?
-Any other investigations done?

I would like to tell you a simple thing: Getting a right diagnosis is the most important aspect of any disease, the treatment then becomes specific.

I would advise you the following if you have not done yet:
-Blood tests: CBC, ESR, Sugar. Liver Function Tests (may be as a baseline if ATT {Anti-tubercular treatment} need to be started)
-Blood: Quantiferon Gold test for TB.
-X-ray of the chest, if doubtful CT scan of the chest to see for the presence of TB in the lungs and / or mediastinal lymph nodes.
-Repeat FNAC
-Mantoux skin test.

All these tests reports have to be taken and considered together to decided whether this is TB or not. This is because the FNAC was not conclusive.
It is possible that another FNAC may be conclusive to tell us whether this is TB or not.

Explanation:
FNAC- is fine needle aspiration cytology. In this a small-bore needle is passed into the mass and aspirated very small part is examined, so it may not be conclusive every time. This is the need to go for multiple FNACs or repeat. If required the whole mass / lymph node is removed to do a formal 'biopsy'. The biopsy of the whole mass is more conclusive, but is avoided in cases where the mass is on an important blood vessel or a nerve to have a margin of safety (as in anterior cervical area). And FNAC gives a good diagnosis in many cases. You can opt for a repeat / biopsy as may be advised by your Doctor.

Go for all the tests as they together give a more clear and conclusive picture.

The impression of your report: Necrotizing granulomatous lymphadentis; possibility of Koch's cannot be ruled out. >> gives me an indication to go for further tests as diagnosis is more important as TB has to be diagnosed conclusively to get further management. It is question of a serious disease being diagnosed or not...

I hope this answer helps you to get a better idea and go ahead for confirmatory diagnosis, please feel free to ask for more or if you feel a gap of communication.

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