Oral neoplasms in pickhandle barracuda Sphyraena jello from India

Abstract

We report the spontaneous occurrence of oral neoplasms in pickhandle barracuda Sphyraena jello Cuvier, 1829 from Parangipettai, on the southeast coast of India. A total of 11736 fish were examined, of which 43 were affected with oral tumours, with an overall prevalence of 0.37%. Gross and clinical symptoms included reddish to grayish-white distended tumourous growths on the gingiva, intra-oral bones and tongue. The tumours exhibited delayed eruption and intra-or extra-oral swelling, varied in consistency from extremely firm to fleshy and released mucinous material. The majority of tumours consisted of numerous clumped toothlets, but some included hardened tissues. Local area invasion/transmission was observed in most cases; however, necropsy examination revealed no gross evidence of distant metastasis into visceral organs. Radiographic examination of compound odontomas revealed distinct unilocular radio-opaque minitoothlets surrounded by defined radiolucency, whereas complex odontomas exhibited unilocular and indistinct radio-opaque masses within a much more extensive radiolucent zone. Histopathologically, the intra-oral tumour lesions were characterized by numerous imperfect (germ) toothlets consisting of a disorganized combination of dental tissues: pulp tissues with manifested and predominantly mixed hard dental tissues of immature dentine and enamel, numerous small to large and round to polyhedral ossicles embedded in hypocellular fibrous stromal tissues and sparsely spaced bland spindloid cells with cleft-like spaces of loose mucoid stroma. Histochemically, the neoplastic lesions stained positive for periodic acid-Schiff and Masson's trichrome. Based on the clinical and histological findings, the tumours were diagnosed as compound odontomas, complex odontomas, odontogenic myxomas, lingual myxomas and psammomatoid ossifying fibromas.

Neoplasia in goldlined seabream, Rhabdosargus sarba (Forsskål, 1775)

“…Psammomatoid ossifying fibroma is a rare tumour in fish. The anal (case 1) lesion observed in seabream resembles tumours in pickhandle barracuda, Sphyraena jello (Singaravel et al., ) in which osteoid fibroma with atypical ossification was observed. Nodular fasciitis is a benign, reactive proliferation of fibroblasts in the subcutaneous tissues and deep fascia.…”

“…Recently, however, we have reported a high incidence of tumours in both cultured and captured fish in India, such as Mugil cephalus (Jithendran, Natarajan, Pramoda, & Thiagarajan, ; Singaravel, Gopalakrishnan, Raja, Vijayakumar, & Asrafuzzaman, ), Sardinella longiceps (Gopalakrishnan et al., ; Sinduja, Vijayakumar, & Gopalakrishnan, ; Singaravel et al. , ; Singaravel, Gopalakrishnan, Vijayakumar, Raja, & Asrafuzzaman, ,b), Sphyraena barracuda (Gopalakrishnan et al., ), Chanos chanos (Ananda Raja, Panigrahi, & Kumar, ), Puntius sarana (Sahoo, Mohanty, Das, Mahapatra, & Saha, ), Sphyraena jello (Singaravel, Gopalakrishnan, Raja, Vijayakumar, & Asrafuzzaman, ,b; Vijayakumar, Gopalakrishnan, Raja, & Sinduja, ), Lates calcarifer (Vijayakumar, Raja, Singaravel, & Gopalakrishnan, ), Arius jella (Singaravel, Gopalakrishnan, Vijayakumar, & Raja, ) and Rastrelliger kanagurta (Singaravel, Gopalakrishnan, & Raja, ). Tumours in goldlined seabream ( R. sarba ) have not previously been seen, and to our knowledge, this is the first such report.…”

Dermal fibroma in a tawny nurse shark, Nebrius ferrugineus (Lesson, 1831)

“…Furthermore, the usefulness of fish as a model for studying human diseases including neoplasms has also prompted researchers to pay much interest in unravelling tumorigenesis in fish (Schmale, Nairn, & Winn, 2007). While there are no systematic studies on fish neoplasms from India, some of the reported tumours include odontoma in pickhandle barracuda, Sphyraena jello (Singaravel et al, 2017), cutaneous myxoma in blackfin sea catfish (Singaravel, Gopalakrishnan, Vijayakumar, & Raja, 2015), and lipoma in a gold fish (Sood et al, 2017). Fibromas are benign neoplasms of mesenchymal origin composed of fibrous connective tissue.…”