https://www.vetsurgeon.org/f/clinical-questions/23195/weird-tumour-the-lab-can-t-identify I have a 9yo, MN pug with a history of incompletely excised mast cell tumours that had been on Masivet until about a year ago as he was lesion free. I saw him with an ulcerated lesion on the main pad of his RH which initially looked like a cut but afteren-USTelligent Community 10https://www.vetsurgeon.org/thread/141885?ContentTypeID=1Tue, 25 Aug 2015 08:49:11 GMT146601cc-3922-4be7-9974-7e1d4e45a66b:815c623b-5035-42d2-b085-4cefc055678cKara Gibson<p>Definitely possible it was an inflammatory change given the response but it did look very similar to how the original tumour started.</p> <p>I guess an effect on CD antigen expression is possible but the lab used tryptase as a marker for mast cells and from the papers I&#39;ve looked at it seems reliable.</p><div style="clear:both;"></div>https://www.vetsurgeon.org/thread/141870?ContentTypeID=1Mon, 24 Aug 2015 16:16:23 GMT146601cc-3922-4be7-9974-7e1d4e45a66b:9ea7d748-969a-424b-b1b8-e4b9a3416a62MattB<p>What if the history of a tyrosine kinase inhibitor has caused down-regulation of some of the CD- antigens on immune cells, thereby skewing the path results?</p> <p></p> <p>Matt</p><div style="clear:both;"></div>https://www.vetsurgeon.org/thread/141695?ContentTypeID=1Thu, 20 Aug 2015 08:46:12 GMT146601cc-3922-4be7-9974-7e1d4e45a66b:5f4bbbaf-77ae-497b-8d73-3dbaf7260e00Gerry Polton<p>Morning all!</p> <p>I can&#39;t shine a particularly bright light on this one, I&#39;m afraid. However, for what it&#39;s worth, my thought process is that this is either a mast cell tumour and the immunohistochemistry has let us down or this is a histiocytic sarcoma with a mysterious accumulation of mast cells on the original sections. Either way, it sounds like it&#39;s come back so if revision surgery could be performed it might be worth considering. Both ought to be responsive to radiotherapy, so that is also an option. Before considering either, we would need to be as confident as possible that there was no detectable disease at other sites, so appropriate imaging to rule out (or in) the presence of metastasis would be appropriate before making any decisions. For systemic histiocytic sarcoma, lomustine is an option. Is it possible that the recent mass is a reactive inflammatory change rather than a recurrence...?</p> <p>Gerry</p><div style="clear:both;"></div>https://www.vetsurgeon.org/thread/141691?ContentTypeID=1Thu, 20 Aug 2015 03:39:05 GMT146601cc-3922-4be7-9974-7e1d4e45a66b:6b2c5cbc-cc82-4e7c-8bf3-d27cf1b99810Kara Gibson<p>Had a very good response to prednisolone so farm just can&#39;t predict how long the effect will last!</p><div style="clear:both;"></div>https://www.vetsurgeon.org/thread/141681?ContentTypeID=1Wed, 19 Aug 2015 16:44:22 GMT146601cc-3922-4be7-9974-7e1d4e45a66b:42955789-3301-4715-9058-315509871bb2Joyce Whitehead<p><a href="/members/gerrypolton" class="internal-link view-user-profile">Gerry Polton</a>&nbsp;</p> <p>Hopefully this will alert him...</p><div style="clear:both;"></div>https://www.vetsurgeon.org/thread/141647?ContentTypeID=1Wed, 19 Aug 2015 10:24:02 GMT146601cc-3922-4be7-9974-7e1d4e45a66b:9f41d9c3-6760-4def-8c43-1f90984b2a84Martin Atkinson<p>Hopefully Gerry Polton will be along soon.</p><div style="clear:both;"></div>https://www.vetsurgeon.org/thread/141636?ContentTypeID=1Wed, 19 Aug 2015 04:32:15 GMT146601cc-3922-4be7-9974-7e1d4e45a66b:dcb04071-22dd-4fbf-8532-6bf0b34ef093Kara Gibson<p>Bump!</p><div style="clear:both;"></div>