{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,26]],"date-time":"2026-10-26T18:09:03Z","timestamp":1793038143522,"version":"4.5.0"},"reference-count":27,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2026,1,29]],"date-time":"2026-01-29T00:00:00Z","timestamp":1769644800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>Canine mammary tumours often present as multiple synchronous nodules, necessitating decisions regarding staging intensity and surgical planning prior to histology. We developed two preoperative nodule-level prediction models using only the medical history and physical examination of client-owned bitches with mammary disease, which were staged using the WHO-modified TNM system with a M0 classification (no distant metastasis) at the time of presentation. This retrospective study analysed 286 surgically excised mammary nodules from 92 dogs managed under a standardised mammary oncology protocol; those with inflammatory mammary carcinoma or distant metastasis were excluded. The outcomes were (i) malignant versus benign\/non-neoplastic histology (for all nodules) and (ii) intermediate\/high histologic grade (II\u2013III versus I) among carcinomas. Separate multivariable Firth penalised logistic regression models accounted for within-dog clustering with dog-level bootstrap internal validation. Multiple imputation was used in a sensitivity analysis for missingness in the detection-to-surgery interval. Malignancy was confirmed in 87\/286 (30.4%) of the nodules (86 carcinomas), including 35\/87 (40.2%) that measured less than 1 cm. Among complete cases (153 nodules), malignancy was associated with age at neutering, maximum tumour diameter, owner-reported rapid growth and a detection-to-surgery interval of more than 3.5 months (an exploratory ROC-derived threshold) with good discrimination (area under the curve (AUC) 0.805; optimism-corrected 0.799) and acceptable calibration. Among carcinomas (83 specimen), previous mammary tumours, bloody nipple discharge and fewer synchronous nodules were associated with intermediate\/high malignancy grade (AUC 0.859). Sensitivity analyses yielded directionally consistent estimates. Routinely available clinical information may provide interpretable preoperative risk stratification to support staging and surgical planning, pending external validation.<\/jats:p>","DOI":"10.3390\/ani16030421","type":"journal-article","created":{"date-parts":[[2026,1,29]],"date-time":"2026-01-29T10:08:57Z","timestamp":1769681337000},"page":"421","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Preoperative Clinical Predictors of Histologic Malignancy and Carcinoma Grade in 286 Canine Mammary Nodules from 92 Bitches: A Retrospective Study"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0736-8791","authenticated-orcid":false,"given":"Manuel","family":"Fuertes-Recuero","sequence":"first","affiliation":[{"name":"Complutense Veterinary Teaching Hospital, Complutense University of Madrid, Avda. Puerta de Hierro s\/n, 28040 Madrid, Spain"},{"name":"Department of Physiology, Veterinary Medicine School, Complutense University of Madrid, Avda. Puerta de Hierro s\/n, 28040 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8531-9069","authenticated-orcid":false,"given":"Paula","family":"Garc\u00eda San Jos\u00e9","sequence":"additional","affiliation":[{"name":"Complutense Veterinary Teaching Hospital, Complutense University of Madrid, Avda. Puerta de Hierro s\/n, 28040 Madrid, Spain"},{"name":"Department of Animal Medicine and Surgery, Veterinary Medicine School, Complutense University of Madrid, Avda. Puerta de Hierro s\/n, 28040 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6969-1597","authenticated-orcid":false,"given":"Guillermo","family":"Valdivia","sequence":"additional","affiliation":[{"name":"Complutense Veterinary Teaching Hospital, Complutense University of Madrid, Avda. Puerta de Hierro s\/n, 28040 Madrid, Spain"},{"name":"Department of Animal Medicine and Surgery, Veterinary Medicine School, Complutense University of Madrid, Avda. Puerta de Hierro s\/n, 28040 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8689-2713","authenticated-orcid":false,"given":"Mar\u00eda","family":"Suarez-Redondo","sequence":"additional","affiliation":[{"name":"Complutense Veterinary Teaching Hospital, Complutense University of Madrid, Avda. Puerta de Hierro s\/n, 28040 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9199-7341","authenticated-orcid":false,"given":"Silvia","family":"Penelo","sequence":"additional","affiliation":[{"name":"Complutense Veterinary Teaching Hospital, Complutense University of Madrid, Avda. Puerta de Hierro s\/n, 28040 Madrid, Spain"},{"name":"Department of Animal Medicine and Surgery, Veterinary Medicine School, Complutense University of Madrid, Avda. Puerta de Hierro s\/n, 28040 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3315-7931","authenticated-orcid":false,"given":"Mario","family":"Arenillas","sequence":"additional","affiliation":[{"name":"Complutense Veterinary Teaching Hospital, Complutense University of Madrid, Avda. Puerta de Hierro s\/n, 28040 Madrid, Spain"},{"name":"Department of Animal Medicine and Surgery, Veterinary Medicine School, Complutense University of Madrid, Avda. Puerta de Hierro s\/n, 28040 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Laura","family":"Camacho-Alonso","sequence":"additional","affiliation":[{"name":"Complutense Veterinary Teaching Hospital, Complutense University of Madrid, Avda. Puerta de Hierro s\/n, 28040 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7135-6280","authenticated-orcid":false,"given":"Laura","family":"Pe\u00f1a","sequence":"additional","affiliation":[{"name":"Complutense Veterinary Teaching Hospital, Complutense University of Madrid, Avda. Puerta de Hierro s\/n, 28040 Madrid, Spain"},{"name":"Department of Animal Medicine and Surgery, Veterinary Medicine School, Complutense University of Madrid, Avda. Puerta de Hierro s\/n, 28040 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0426-0083","authenticated-orcid":false,"given":"Dolores","family":"P\u00e9rez-Alenza","sequence":"additional","affiliation":[{"name":"Complutense Veterinary Teaching Hospital, Complutense University of Madrid, Avda. Puerta de Hierro s\/n, 28040 Madrid, Spain"},{"name":"Department of Animal Medicine and Surgery, Veterinary Medicine School, Complutense University of Madrid, Avda. Puerta de Hierro s\/n, 28040 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8242-2658","authenticated-orcid":false,"given":"Gustavo","family":"Ortiz-D\u00edez","sequence":"additional","affiliation":[{"name":"Complutense Veterinary Teaching Hospital, Complutense University of Madrid, Avda. Puerta de Hierro s\/n, 28040 Madrid, Spain"},{"name":"Department of Physiology, Veterinary Medicine School, Complutense University of Madrid, Avda. Puerta de Hierro s\/n, 28040 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Salas, Y., M\u00e1rquez, A., Diaz, D., and Romero, L. (2015). Epidemiological Study of Mammary Tumors in Female Dogs Diagnosed during the Period 2002\u20132012: A Growing Animal Health Problem. PLoS ONE, 10.","DOI":"10.1371\/journal.pone.0127381"},{"key":"ref_2","unstructured":"Zappulli, V., Kiupel, M., Pe\u00f1a, L., Rasotto, R., Goldschmidt, M.H., Gama, A., Scruggs, J.L., and Davis-Thompson Foundation (2018). Surgical Pathology of Tumors of Domestic Animals Volume 2, Mammary Tumors, Davis-Thompson Foundation. 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