Fibroepithelial hamartoma in a domestic pig

Pulmonary hamartoma in an elk calf

Hamartomas are benign tumor-like lesions composed of disorganized growth of mature mesenchymal or epithelial tissues indigenous to the organ involved. Sporadically observed in ruminants, vascular, fibrous, nasal, and pulmonary hamartomas have been reported in calves; pulmonary and cutaneous forms have been reported in sheep. A full-term elk calf found dead had a large intrathoracic mass replacing the left caudal lung lobe and compressing other thoracic organs. Histologically, cross- and tangential sections of bronchi were separated by collagenous mesenchyme and irregularly shaped canaliculi and saccules resembling terminal bronchioles. Rarely present were regions in which saccules, lined by simple cuboidal epithelium, transitioned into attenuated epithelium lining fully developed alveoli. These findings are consistent with a pulmonary hamartoma. To our knowledge, pulmonary hamartoma has not been reported previously in a non-domestic ruminant.

Neoplastic lesions in domestic pigs detected at slaughter: literature review and a 20-year review (1998-2018) of carcass inspection in Catalonia

Background

The present paper reviews the occurrence of neoplasms in swine and presents a case series of 56 tumors submitted to the Slaughterhouse Support Network (Servei de Suport a Escorxadors [SESC] IRTA-CReSA]) from slaughtered pigs from 1998 to 2018 (April) in Catalonia (Spain). The aim of the study was to describe the spectrum of spontaneous neoplastic lesions found in slaughtered pigs and to compare the reported tumor cases with previous published data. Lymphoid neoplasms were characterized and classified using the WHO classification adapted for animals.

Results

The most reported neoplasm during this period was lymphoma (28). Within lymphomas, the B-cell type was the most common, being the diffuse large B-cell lymphoma (15/28) the most represented subtype. Other submitted non-lymphoid neoplasms included melanoma (7), nephroblastoma (3), mast cell tumor (2), liposarcoma (2), osteochondromatosis (2), papillary cystadenocarcinoma (1), peripheral nerve sheath tumor (1), lymphoid leukemia (1), fibropapilloma (1), hemangiosarcoma (1), hepatoma (1), histiocytic sarcoma (1), pheochromocytoma (1) and osteosarcoma (1).

Conclusions

The existence of a well-established Slaughterhouse Support Network allowed the compilation of comprehensive data for further epidemiological and pathological studies, particularly about less commonly reported lesions in livestock such as neoplasms in pigs.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40813-021-00207-0.

Patho-morphological and immunohistochemical diagnosis of fibrous tissue pulmonary hamartoma in young buffaloes

Hamartoma is a developmental disorder characterized by the presence of well-differentiated tissue, of multiple types, in excess at its normal location. The present study describes a fibrous tissue pulmonary hamartoma in two buffaloes. Grossly, there were large pale white masses present on the left diaphragmatic lobe in both cases. Microscopic examination of the lungs revealed that the bronchioles were dilated and showed many terminal respiratory bronchioles lined by a single layer of cuboidal epithelium supported by thick bands of collagenous tissue. Alveoli were distorted and separated by wide bands of connective tissues. Interalveolar septa were greatly expanded by collagen fiber proliferation and subsequent fibrosis. Fibrous connective tissues were demonstrated by immunohistochemistry (IHC) and Masson's Trichrome staining (MTS). Based on gross and histological examination, coupled with IHC and MTS, it was possible to confirm a case of hamartoma, which is rarely reported worldwide and is the first reported case from India.

Respiratory epithelial adenomatoid hamartoma in a dog

A 6-month-old, intact, male Weimaraner dog presented to the veterinary teaching hospital for bilateral mucopurulent ocular and nasal discharge that began at approximately 10 weeks of age. A computed tomography scan showed an expansile soft-tissue mass involving both frontal sinuses, the ethmoid regions, and nasal cavities with lysis of the maxillary turbinates and hyperostosis of the walls of the frontal sinus. The dog was euthanized after complications during a trephination and biopsy procedure. At necropsy, a large, tan, papillary, gelatinous mass filled the entire nasal cavity and frontal sinus. The mass was composed of large fronds of loose fibrovascular stroma covered by a single layer of pseudostratified, columnar, ciliated epithelium and intermixed goblet cells. The cells occasionally formed glandular structures that were continuous with the surface epithelium. The mass was diagnosed as a respiratory epithelial adenomatoid hamartoma based on the morphologic appearance.