Local invasion by laryngeal carcinoma?the importance of focal (metaplastic) ossification within laryngeal cartilage

Abstract

Patterns of cartilage invasion by squamous carcinoma were examined in 34 consecutive laryngectomy specimens with particular reference to selective involvement of ossified cartilage. Direct infiltration of the laryngeal framework was demonstrated in 17 cases--16 (out of 17) transglottic carcinomas and in a simgle example of a combined glottic and infraglottic tumour. The susceptibility of ossified laryngeal cartilage to tumour invasion was confirmed, and morphological studies ahve clarified the underlying mechanisms. Invasion is a largely indirect process dominated by local bone destruction by osteoclasts, operating in front of the advancing tumour. One established, carcinoma cells infiltrate and erode bone alone, and the osteoclasts disappear. Reasons for the particular susceptibility of ossified laryngeal cartilage to tumour invasion are discussed and attention is drawn to the role of the tumour-associated osteoclast activating factors such as postaglandins. Therapeutic implications of cartilage invasion are noted.

Some mechanisms of local bone destruction by squamous carcinomas of the head and neck

“…The osteoclastic response then subsides and squamous-carcinoma cells, alone, continue to spread into the bone. A similar sequence of events has been described in relation to squamous carcinomas invading metaplastic bone in the ageing, focally ossified larynx (Carter & Tanner, 1979).…”

“…The slides were coded beforehand, but histological differences between the 2 groups were readily apparent (Fig. 4) Carter & Pittam, 1980;Carter & Tanner, 1979). These morphological features are not specific, and the changes observed are comparable to those associated with the growth of blood-borne skeletal metastases of various kinds (Galasko, 1975(Galasko, , 1976.…”

Prostaglandin-like material extracted from squamous carcinomas of the head and neck

“…Bennett et al, 1979) though the numbers of patients here are small. Nevertheless, prostaglandins associated with osteolytic primary squamous carcinomas of the head and neck may facilitate the direct spread of strategically placed tumours to adjacent bone or ossified cartilage (Carter et al, 1980;Carter & Tanner, 1979).…”

“…Prostaglandins and other lessclearly defined "tumour-associated" products may be involved in the establishment and growth of metastases in bone and possibly in other sites (Carter, 1978;Bennett, 1979). Prostaglandin E2 (PGE2) and some other prostanoids stimulate osteoclasts (Galasko, 1976;Carter, 1978;Bennett, 1979) and the recent observation of pronounced osteoclastic activity associated with squamous carcinomas of the head and neck invading bone (Carter & Tanner, 1979;Carter et al, 1980) prompted the present investigation.…”

The Cricothyroid Space: Topography and Clinical Implications

“…Ossified regions of the laryngeal skeleton are at a high risk for tumorous invasion because of their high vascularization |Olszewski. 1976; Carter and Tanner, 1979;Kirchner. 1984],…”