Chondroma in rufescent tiger-heron (Tigrisoma lineatum): case report

Condroma em socó-boi (Tigrisoma leneatum): relato de caso

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Chondroma in rufescent tiger-heron (Tigrisoma lineatum): case report

Condroma em socó-boi (Tigrisoma leneatum): relato de caso

Alexandre Aparecido Mattos da Silva REGO¹; Eliana Reiko MATUSHIMA¹; Maria Cândida MIGUEL²

Correspondence to:

Eliana Reiko Matushima

Departamento de Patologia

Faculdade de Medicina Veterinária e Zootecnia da USP

Cidade Universitária Armando de Salles Oliveira

Av. Orlando Marques de Paiva, 87

05508-000 – São Paulo – SP

SUMMARY

The paper describes a chondroma affecting the left metacarpus of a free-ranging rufescent tiger-heron (Tigrisoma lineatum). There are very few reports of such neoplastic process in this avian species.

UNITERMS: Neoplasms; Chondroma; Birds.

Reports of neoplastic process on wild animals, especially on free ranging birds, are rare or sporadic. The present work describes a tumor on the left metacarpial area affecting a free-ranging rufescent tiger-heron (Tigrisoma lineatum). The bird was sinantropic to the Santa Bárbara d’Oeste Ecological Park, SP – Brazil. The tumor was surgically excised and the bird was promptly released to the wild.

Fragments from the tumor were cut into 1 cm³, fixed in 10% formalin solution and submitted to the Faculty of Veterinary Medicine and Zootechny – University of São Paulo, to be processed according to histological routine procedures. Cuts of 5 micrometers were obtained and stained with Hematoxilin-Eosin (HE).

Histopathologic analysis revealed a non capsulated neoplastic tissue of mesenchymal origin formed by chrondroblasts and chrondocytes distributed in isolated nodules with irregular limits and surrounded by a delicate net of lose connective tissues (Fig. 1). Cellular pleomorphism was not very evident, chrondrocytes were well differentiated, their nuclei were round and well defined and nucleoli were usually lonely, peripheral and very evident. No mitosis could be seen. Inflammatory infiltration consisted basically by mononuclear cells and heterophyls surrounding cartilaginous lobuli and inserting themselves into the stroma. Interstitial haemorrhage foci, without necrosis, were also observed.

Figure 1

Chondromas are benign neoplams arising from the cartilaginous tissue. In Veterinary Medicine, the term chondroma is also used to described any benign proliferation of the cartilage, such as extraskeleton chondroma from mixed tumors of the mammary gland of dog, synovial and bursal chondromas, osteochondromas, enchondromas and many non-classified bone chondromas³.

Usually, these tumors grow slowly, producing minor bone deformations. Clinical signs are associated to size and localization of the neoplasm. Grossly, chondromas are variable in size, multilobular, firms, surrounded by a fibrous capsule, displaying a whitish discoloration. Histologically, are formed by irregular lobules of hyaline cartilage. The morphology of neoplastic chondrocytes tends to be uniform. The surrounding skin may shows atrophy, ulceration and suppurative exudation, and invasion of the adjacent venous vessels may occur due to extensive growth¹. According to Ewing¹, in humans chondromas might have a traumatic origin.

Differences between chondromas and malignant cartilaginous neoplasms are not always clearly identified; there are some transitional tumors and some neoplastic processes believed to be benign might acquire malignant characteristics^1,6. In men chondromas are most frequently found affecting the metacarpal and phalangeal areas.

Chondromas have already been seen on practically every domestic animals^2,4. Sullivan⁵ described chondromas and chondrosarcomas in domestic animals, specially sheeps. However, neoplasms arising from the cartilage are rarely reported in wild birds⁶, and little information regarding these processes are available in the current literature. The morphological characteristics seen in the present case are compatible with those depicted elsewhere, assuring that this tumor represents a rare report of chondroma in wild birds.

RESUMO

Relata-se a ocorrência de neoplasia em Tigrisoma lineatum (socó-boi), localizada na região metacarpiana esquerda, caracterizada histologicamente como condroma. Este é um dos primeiros relatos desta patologia em indivíduos desta espécie.

UNITERMOS: Neoplasia; Condroma; Ave.

Received: 12/06/1997

Accepted: 05/08/1998

• ¹
  - EWING, A.M.J. Neoplastic diseases Philadelphia : W.B. Saunders, 1941. 1160p.
• ²
  - FORMAD, R.J. Tumor of domestic animals. USDA Bull, p.1449, 1926.
• ³
  - MOULTON, J.E. Tumors in domestic animals Los Angeles : University of California Press, 1990. p.173-4.
• ⁴
  - RIDDELL, C. Avian histopathology Saskatoon : American Association of Avian Pathologists, 1987. p.24.
• ⁵
  - SULLIVAN, D.J. Cartilaginous tumors (Chondroma and Chondrosarcoma) in animals. American Journal of Veterinary Research, v.21, n.83, p.531, 1960.
• ⁶
  - WILLIS, R.A. Pathology of tumors London : Butterworth, 1948. 992p.

1

Departamento de Patologia da Faculdade de Medicina Veterinária e Zootecnia da USP – SP

² Parque Ecológico Municipal, Santa Bárbara d’Oeste – SP

Publication Dates

• Publication in this collection
  20 Sept 2000
• Date of issue
  1999

History

• Received
  12 June 1997
• Accepted
  05 Aug 1998