Langerhans cell histiocytosis of an intra-mammary lymph node in an 18-year-old woman

Enlarged lymph nodes diagnosed with Langerhans cell histiocytosis found in a direct inguinal hernia: a case report

It is unusual that an unexpected mass is encountered within a hernia sac. This report describes a patient diagnosed with Langerhans cell histiocytosis (LCH) after surgery for an inguinal hernia. A 64-year-old male patient presented with inguinal mass over a 1-year period. Direct inguinal hernias were found in both sides, and enlarged lymph nodes were found in both hernia sacs. Laparoscopic totally extraperitoneal repair was done, and one enlarged lymph node within inguinal hernia sac was excised for diagnostic purposes. Microscopic findings showed the distinctive cytologic features of Langerhans cells and immunohistochemical staining are positive for CD1a and S-100. LCH is a rare disorder, and the involvement of the lymph nodes with no other sites of disease is uncommon. To the best of our knowledge, this is the first report of LCH within an inguinal hernia sac. Multidisciplinary approach should be considered to provide better detection and treatment.

Marking vertebrates langerhans cells, from fish to mammals

Langerhans cells (LCs) are specialized dendritic cells (DCs) that play a defense role in recognizing foreign antigens, in tissue where antigenic exposures occur, as in the skin and mucous membranes. LCs are able to continuously move within the tissues thanks to dendritic contraction and distension performing their surveillance and/or phagocytosis role. These cells are characterized by the presence of Birbeck granules in their cytoplasm, involved in endocytosis. LCs have been characterized in several classes of vertebrates, from fish to mammals using different histological and molecular techniques. The aim of the present review is to define the state of art and the need of information about immunohistochemical markers of LCs in different classes of vertebrates. The most used immunohistochemical (IHC) markers are Langerin/CD207, CD1a, S-100 and TLR. These IHC markers are described in relation to their finding in different vertebrate classes with phylogenetical considerations. Among the four markers, Langerin/CD207 and TLR have the widest spectrum of cross reactivity in LCs.