{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,4]],"date-time":"2026-09-04T06:12:25Z","timestamp":1788502345682,"version":"build-2803163510"},"reference-count":35,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,9,4]],"date-time":"2026-09-04T00:00:00Z","timestamp":1788480000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Vet. Sci."],"abstract":"<jats:p>\n                    Cutaneous manifestations of feline leishmaniosis may occur at anatomical sites commonly affected by squamous cell carcinoma (SCC), creating potential diagnostic overlap. Although concurrent\n                    <jats:italic>Leishmania<\/jats:italic>\n                    infection and SCC have been described in individual cats, the presence of parasite DNA in feline SCC tissue has not been systematically investigated. This retrospective cross-sectional study evaluated 219 formalin-fixed, paraffin-embedded feline SCC samples submitted to a veterinary diagnostic laboratory in Portugal between 2020 and 2023. Samples were screened using a\n                    <jats:italic>Leishmania<\/jats:italic>\n                    -genus-specific nested PCR targeting SSU rDNA. PCR-positive cases were subsequently analyzed at four additional loci (\n                    <jats:italic>cytB<\/jats:italic>\n                    ,\n                    <jats:italic>g6pdh<\/jats:italic>\n                    ,\n                    <jats:italic>hsp70<\/jats:italic>\n                    , and ITS rDNA) and reassessed histopathologically.\n                    <jats:italic>Leishmania<\/jats:italic>\n                    spp. SSU rDNA was detected in 3\/219 samples (1.4%; 95% CI: 0.5\u20133.9%), corresponding to SCC lesions on the pinna, nasal planum, and eyelid. Molecular characterization was possible in one case, involving an SCC of the nasal planum. Phylogenetic analysis showed that the\n                    <jats:italic>hsp70<\/jats:italic>\n                    sequence clustered with reference sequences of\n                    <jats:italic>L. infantum<\/jats:italic>\n                    , whereas the\n                    <jats:italic>cytB<\/jats:italic>\n                    sequence grouped within the\n                    <jats:italic>L. donovani<\/jats:italic>\n                    complex without species-level resolution. In the same lesion, structures morphologically compatible with amastigotes were observed within macrophages in the tumor-associated inflammatory infiltrate. Overall,\n                    <jats:italic>Leishmania<\/jats:italic>\n                    DNA was detected in only a small proportion of feline SCCs, and the findings support coexistence rather than an association between infection and tumor development. These findings have direct diagnostic relevance in endemic areas, where histopathologic confirmation of SCC should not preclude investigation for concurrent\n                    <jats:italic>Leishmania<\/jats:italic>\n                    infection when clinical or epidemiologic suspicion persists.\n                  <\/jats:p>","DOI":"10.3389\/fvets.2026.1952747","type":"journal-article","created":{"date-parts":[[2026,9,4]],"date-time":"2026-09-04T05:28:36Z","timestamp":1788499716000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Molecular detection of Leishmania spp. in feline squamous cell carcinoma in Portugal"],"prefix":"10.3389","volume":"13","author":[{"given":"Carolina","family":"Oliveira","sequence":"first","affiliation":[{"name":"Faculty of Veterinary Medicine, Lus\u00f3fona University, Lisbon University Centre","place":["Lisbon, Portugal"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joana","family":"Santos","sequence":"additional","affiliation":[{"name":"Faculty of Veterinary Medicine, Lus\u00f3fona University, Lisbon University Centre","place":["Lisbon, Portugal"]},{"name":"Research in Veterinary Medicine (I-MVET), Faculty of Veterinary Medicine, Lus\u00f3fona University, Lisbon University Centre","place":["Lisbon, Portugal"]},{"name":"DNAtech Veterinary Laboratory","place":["Lisbon, Portugal"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andreia","family":"Valen\u00e7a","sequence":"additional","affiliation":[{"name":"Faculty of Veterinary Medicine, Lus\u00f3fona University, Lisbon University Centre","place":["Lisbon, Portugal"]},{"name":"Research in Veterinary Medicine (I-MVET), Faculty of Veterinary Medicine, Lus\u00f3fona University, Lisbon University Centre","place":["Lisbon, Portugal"]},{"name":"Superior School of Health, Protection and Animal Welfare (ESPA), Polytechnic Institute of Lusophony (IPLUSO)","place":["Lisbon, Portugal"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jos\u00e9","family":"Catarino","sequence":"additional","affiliation":[{"name":"Faculty of Veterinary Medicine, Lus\u00f3fona University, Lisbon University Centre","place":["Lisbon, Portugal"]},{"name":"Research in Veterinary Medicine (I-MVET), Faculty of Veterinary Medicine, Lus\u00f3fona University, Lisbon University Centre","place":["Lisbon, Portugal"]},{"name":"DNAtech Veterinary Laboratory","place":["Lisbon, Portugal"]},{"name":"Superior School of Health, Protection and Animal Welfare (ESPA), Polytechnic Institute of Lusophony (IPLUSO)","place":["Lisbon, Portugal"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"David","family":"Ramilo","sequence":"additional","affiliation":[{"name":"Faculty of Veterinary Medicine, Lus\u00f3fona University, Lisbon University Centre","place":["Lisbon, Portugal"]},{"name":"Research in Veterinary Medicine (I-MVET), Faculty of Veterinary Medicine, Lus\u00f3fona University, Lisbon University Centre","place":["Lisbon, Portugal"]},{"name":"Veterinary and Animal Research Centre (CECAV), Faculty of Veterinary Medicine, Lus\u00f3fona University, Lisbon University Centre","place":["Lisbon, Portugal"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Martim","family":"Matias","sequence":"additional","affiliation":[{"name":"Research in Veterinary Medicine (I-MVET), Faculty of Veterinary Medicine, Lus\u00f3fona University, Lisbon University Centre","place":["Lisbon, Portugal"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Margarida","family":"Alves","sequence":"additional","affiliation":[{"name":"Faculty of Veterinary Medicine, Lus\u00f3fona University, Lisbon University Centre","place":["Lisbon, Portugal"]},{"name":"Research in Veterinary Medicine (I-MVET), Faculty of Veterinary Medicine, Lus\u00f3fona University, Lisbon University Centre","place":["Lisbon, Portugal"]},{"name":"Veterinary and Animal Research Centre (CECAV), Faculty of Veterinary Medicine, Lus\u00f3fona University, Lisbon University Centre","place":["Lisbon, Portugal"]},{"name":"Research Center for Biosciences and Health Technologies (CBIOS), Lisbon University Centre, Lus\u00f3fona University","place":["Lisbon, Portugal"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Carla","family":"Maia","sequence":"additional","affiliation":[{"name":"Global Health and Tropical Medicine (GHTM), LA-REAL, Instituto de Higiene e Medicina Tropical, Universidade Nova de Lisboa","place":["Lisbon, Portugal"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pedro","family":"Fa\u00edsca","sequence":"additional","affiliation":[{"name":"Faculty of Veterinary Medicine, Lus\u00f3fona University, Lisbon University Centre","place":["Lisbon, Portugal"]},{"name":"Research in Veterinary Medicine (I-MVET), Faculty of Veterinary Medicine, Lus\u00f3fona University, Lisbon University Centre","place":["Lisbon, Portugal"]},{"name":"DNAtech Veterinary Laboratory","place":["Lisbon, Portugal"]},{"name":"Veterinary and Animal Research Centre (CECAV), Faculty of Veterinary Medicine, Lus\u00f3fona University, Lisbon University Centre","place":["Lisbon, Portugal"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joaquim","family":"Henriques","sequence":"additional","affiliation":[{"name":"Faculty of Veterinary Medicine, Lus\u00f3fona University, Lisbon University Centre","place":["Lisbon, Portugal"]},{"name":"Research in Veterinary Medicine (I-MVET), Faculty of Veterinary Medicine, Lus\u00f3fona University, Lisbon University Centre","place":["Lisbon, Portugal"]},{"name":"iNOVA4Health, NOVA Medical School, Universidade Nova de Lisboa","place":["Lisbon, Portugal"]},{"name":"Anicura Atl\u00e2ntico Hospital Veterin\u00e1rio","place":["Mafra, Portugal"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andr\u00e9","family":"Pereira","sequence":"additional","affiliation":[{"name":"Faculty of Veterinary Medicine, Lus\u00f3fona University, Lisbon University Centre","place":["Lisbon, Portugal"]},{"name":"Research in Veterinary Medicine (I-MVET), Faculty of Veterinary Medicine, Lus\u00f3fona University, Lisbon University Centre","place":["Lisbon, Portugal"]},{"name":"Superior School of Health, Protection and Animal Welfare (ESPA), Polytechnic Institute of Lusophony (IPLUSO)","place":["Lisbon, Portugal"]},{"name":"Veterinary and Animal Research Centre (CECAV), Faculty of Veterinary Medicine, Lus\u00f3fona University, Lisbon University Centre","place":["Lisbon, Portugal"]},{"name":"Global Health and Tropical Medicine (GHTM), LA-REAL, Instituto de Higiene e Medicina Tropical, Universidade Nova de Lisboa","place":["Lisbon, Portugal"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,9,4]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"100035","DOI":"10.1016\/j.crpvbd.2021.100035","article-title":"Leishmania infection in cats and feline leishmaniosis: an updated review with a proposal of a diagnosis algorithm and prevention guidelines","volume":"1","author":"Pereira","year":"2021","journal-title":"Curr Res Parasitol Vector Borne Dis"},{"key":"ref2","doi-asserted-by":"publisher","first-page":"131","DOI":"10.1016\/j.vetpar.2018.01.012","article-title":"Feline leishmaniosis: is the cat a small dog?","volume":"251","author":"Pennisi","year":"2018","journal-title":"Vet Parasitol"},{"key":"ref3","doi-asserted-by":"publisher","first-page":"106710","DOI":"10.1016\/j.actatropica.2022.106710","article-title":"A global perspective on non-autochthonous canine and feline Leishmania infection and leishmaniosis in the 21st 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