{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,2]],"date-time":"2026-03-02T14:19:00Z","timestamp":1772461140323,"version":"3.50.1"},"reference-count":20,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2026,2,28]],"date-time":"2026-02-28T00:00:00Z","timestamp":1772236800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Veterinary Sciences"],"abstract":"<jats:p>This report describes an atypical presentation of pyogranulomatous panniculitis and perifolliculitis in an 11-year-old mixed-breed dog. The patient presented with a firm, warm cervical mass that progressed with unusual aggression over a matter of days. While advanced diagnostics, including Computed Tomography (CT) and Ultrasonography (US), provided critical data regarding the lesion\u2019s extent, they proved deceptive in determining its etiology; the imaging demonstrated apparent continuity between the mass and the adjacent musculature, strongly favoring a diagnosis of invasive neoplasia. Due to this diagnostic ambiguity and the mass\u2019s rapid expansion, the lesion was surgically excised for definitive analysis. Surprisingly, histopathological examination contradicted the clinical and radiographic suspicion of malignancy, identifying instead a severe multifocal-to-coalescing inflammatory process. The patient recovered rapidly postoperatively with no evidence of recurrence. This case highlights that while imaging is an invaluable tool for surgical planning, it cannot reliably differentiate between aggressive inflammatory processes and invasive masses. The patient\u2019s rapid recovery with no recurrence reinforces this limitation. Consequently, histopathological examination remains the gold standard for definitively diagnosing and guiding the management of rapidly expanding lesions.<\/jats:p>","DOI":"10.3390\/vetsci13030232","type":"journal-article","created":{"date-parts":[[2026,3,2]],"date-time":"2026-03-02T12:39:56Z","timestamp":1772455196000},"page":"232","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Case Report: Pyogranulomatous Panniculitis Mimicking an Invasive Subcutaneous Mass with Muscular Pseudo-Invasion in a Dog"],"prefix":"10.3390","volume":"13","author":[{"given":"Changmin","family":"Park","sequence":"first","affiliation":[{"name":"Department of Veterinary Surgery, College of Veterinary Medicine, Konkuk University, Neungdongro 120, Seoul 05029, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bumgyu","family":"Shin","sequence":"additional","affiliation":[{"name":"Department of Veterinary Surgery, College of Veterinary Medicine, Konkuk University, Neungdongro 120, Seoul 05029, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0006-5984-4381","authenticated-orcid":false,"given":"Sangyul","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Veterinary Surgery, College of Veterinary Medicine, Konkuk University, Neungdongro 120, Seoul 05029, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hyung-Seok","family":"Seo","sequence":"additional","affiliation":[{"name":"Department of Veterinary Surgery, College of Veterinary Medicine, Konkuk University, Neungdongro 120, Seoul 05029, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6425-7716","authenticated-orcid":false,"given":"Jung-Moon","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Veterinary Surgery, College of Veterinary Medicine, Konkuk University, Neungdongro 120, Seoul 05029, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hwi-Yool","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Veterinary Surgery, College of Veterinary Medicine, Konkuk University, Neungdongro 120, Seoul 05029, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,2,28]]},"reference":[{"key":"ref_1","unstructured":"Scott, D.W., Miller, W.H., and Griffin, C.E. (1995). Muller & Kirk\u2019s Small Animal Dermatology, Elsevier."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"278","DOI":"10.1111\/j.1939-1676.2009.0449.x","article-title":"Canine sterile nodular panniculitis: A retrospective study of 14 cases","volume":"24","author":"Inteeworn","year":"2010","journal-title":"J. Vet. Intern. Med."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"27","DOI":"10.1016\/j.cvsm.2018.08.003","article-title":"Sterile Pyogranulomatous Dermatitis and Panniculitis","volume":"49","author":"Schissler","year":"2019","journal-title":"Vet. Clin. N. Am. Small Anim. Pract."},{"key":"ref_4","first-page":"177","article-title":"Diagnostic dermatology dermatologie diagnostique","volume":"47","author":"Hall","year":"2006","journal-title":"Can. Vet. 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Sci."}],"container-title":["Veterinary Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2306-7381\/13\/3\/232\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,3,2]],"date-time":"2026-03-02T13:21:45Z","timestamp":1772457705000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2306-7381\/13\/3\/232"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,2,28]]},"references-count":20,"journal-issue":{"issue":"3","published-online":{"date-parts":[[2026,3]]}},"alternative-id":["vetsci13030232"],"URL":"https:\/\/doi.org\/10.3390\/vetsci13030232","relation":{},"ISSN":["2306-7381"],"issn-type":[{"value":"2306-7381","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,2,28]]}}}