Assessment of cases of lichenoid granulomatous stomatitis in respect to demographics, histological features, and subcategories in known population

Introduction: Lichenoid granulomatous dermatitis (LGD) is widely encountered lesions with both oral as well as dermal manifestation. Present study was done to evaluate lichenoid granulomatous stomatitis cases. Materials and methods: 226 biopsies were exposed to special stains such as acid-fast bacilli (AFB), immunohistochemical staining for CD 68 and Grocott methenamine-silver (GMS), and periodic acid‐Schiff (PAS) stains. Results: Out of 226 patients, males were 84 and females were 142. Maximum cases were seen in age group 40–60 years (122) followed by >60 years (56) and 20–40 years (48). The common site was buccal mucosa seen in 128 (56.6%) cases followed by vestibule in 30 (13.2%), gingiva in 26 (11.5%), tongue in 20 (8.8%), lip in 12 (5.3%) and palate in 10 (4.4%). The common lesion was oral lichen planus seen in 142 (62.8%), carcinoma in situ in 12 (5.3%), squamous cell carcinoma in 8 (3.53%), pemphigus vulgaris in 10 (4.42%), leukoplakia in 24 (10.6%) and pemphigoid in 30 (13.2%) cases. Most lesions were of type I seen in 117 (51.7%) cases. Conclusion: Lichenoid granulomatous dermatitis poses variety of clinical as well as oral features. A long standing follows up and consideration of differential diagnosis is mandatory for better management of patients.

Prevalence and distribution of canine neoplastic and non-neoplastic cutaneous lesions in Serbia: a retrospective study of 2432 Cases (2011 – Mid 2021)

Cutaneous lesions, especially skin tumors in dogs, are among the most common lesions in this animal species. The aim of this study was to identify the most common types of canine cutaneous lesions, to determine the absolute and relative frequency of each type of cutaneous lesion, anatomical locations, mean age, as well as gender and breed distribution. The examination included all samples of cutaneous lesions in dogs obtained by surgical biopsy in veterinary clinics and examined at the Laboratory of the Department of Pathology at the Faculty of Veterinary Medicine, University of Belgrade from the 1st January 2011 to the 1st July 2021. In this period (126 months), a total of 2432 samples of cutaneous lesions were examined, of which 1984 (81.58%) were tumors (1037/1984, 52.27% benign and 947/1984, 47.73% malignant) and 448 (18.42%) non-neoplastic cutaneous lesions. The most commonly found cutaneous tumors were: mast cell tumor (17.34% of all tumors), histiocytoma (9.78%), papilloma (7.91%), lipoma (7.81%), squamous cell carcinoma (7.36%), trichoblastoma (4.44%), hepatoid adenoma (4.39%) and malignant melanoma (4.18%). The most common non-neoplastic cutaneous lesions were: follicular cyst(s) (35.04% of all non-neoplastic lesions), pyogranulomatous chronic dermatitis (23.88%), lymphocytic dermatitis (7.37%), hyperkeratosis (4.24%), and granulomatous dermatitis (3.79%). Our results substantially confirm previously reported data regarding cutaneous neoplastic and nonneoplastic lesions in dogs, and provide updated information on their frequency, animal age, anatomic location and breed distributions.

Palisading granulomatous dermatitis and panniculitis (palisading granuloma) of dogs

Palisading granulomatous dermatitis and panniculitis is recognized in various cutaneous inflammatory lesions secondary to presumed collagen damage. Cutaneous nodules with a palisading arrangement of histiocytes surrounding foci of collagen degeneration have been clinically termed palisading granuloma in dogs. Study aims were to characterize the cellular infiltrate of canine palisading granuloma and document salient clinical features. Inclusion criteria were met for 36 dogs and encompassed nodular dermal and subcutaneous histiocyte-predominant cellular infiltrates targeting and enveloping collagen fibers/necrotic foci with palisading configurations. Infectious causes were ruled out via standard histochemical stains and/or clinical data. Medical records were reviewed for signalment, clinical features, treatment, outcome, and comorbidities. Immunohistochemistry (IBA1, CD204, E-cadherin) and Masson’s trichrome stain were used to assess histiocytic populations and dermal collagen, respectively. The histiocytes had moderate or strong immunolabeling for IBA1 and CD204 in 36/36 dogs (100%) and mild positive immunolabeling for E-cadherin in 3/36 dogs (8%). Alteration of collagen was graded as moderate or strong in 32/36 dogs (89%) and mild in 3/36 dogs (8%). Large breeds predominated with 30/36 dogs (83%) being ≥23 kg. Focal nodules were identified in 31/36 dogs (86%). The head/face were involved in 19/36 dogs (53%) and the extremities in 18/36 dogs (50%). Lesions from the 5/36 dogs (14%) with multiple nodules contained prominent eosinophilic infiltrates. Following excision, there was no evidence of recurrence. In conclusion, palisading granulomas are a distinct, non-neoplastic, histiocyte-predominant inflammatory condition in dogs associated with altered dermal collagen and favorable prognosis.