Granulomatous inflammation in lymph nodes draining cancer: A coincidence or a significant association!

Granulomatous inflammation is considered to be an immune mechanism against infections or certain non-neoplastic conditions. Rarely granuloma formation may be noted in neoplastic disorders also. However a granulomatous response in the lymph nodes draining cancers is unusual. Such granulomas may sometimes show tumour cells in their centre. The exact cause of this phenomenon is not known but an immunologic reaction to tumour antigens has been suggested. A close scrutiny of such granuloma is necessary to avoid under diagnosis of a metastatic disease. Subtle morphological features which may be helpful in differentiating a co-existing infection or tumour induced granuloma need to be addressed. Moreover the biologic significance of such a granulomatous response in inducing tumour remission or in shielding tumour cells from host lymphocytes also requires further investigation.