SUMMARY A series of nine cases of fibroma of tendon sheath is described including details of the ultrastructural features of two cases. The series was composed of lesions from six males and three females with a mean age of 38 yr. The most common site of involvement was the hand (including fingers) and the mean greatest diameter was 19 mm. Typically the tumours were lobulated and microscopically there was a collagenous stroma with spindle and stellate cells in a moderate degree of cellularity. One recurrence was noted in the series. The lesion was distinguished from circumscribed fibromatosis, nodular fasciitis, neurofibroma, leiomyoma, scar tissue, giant cell tumour of tendon sheath (localised nodular tenosynovitis) and fibrous histiocytoma. Ultrastructural studies revealed that the large majority of cells present in the two cases studied were myofibroblasts and fibroma of tendon sheath is therefore the third instance of a benign tumour containing these cells (the other two being dermatofibroma and giant cell fibroma of the oral mucosa).In his classification of tumours of tendon sheath Buxton' considered that benign tumours included (i) lipoma, (ii) fibroma, (iii) chondroma and (iv) ganglion. Obviously the latter would not be considered a true neoplasm and the other three at first sight would be considered rare. Buxton also referred to a "giant celled myeloma" which was benign but liable to recur locally. It is obvious that this entity equates to the so-called giant cell tumour of tendon sheath a lesion which is probably not a true neoplasm and which is best regarded as a nodular tenosynovitis being a reactive proliferation of both A and B tenosynoviocytes.2 Buxton regarded tendon sheath fibroma as uncommon and described a specimen from near the ankle and which was in the Museum of the Royal College of Surgeons of England. Geschickter and Copeland3 described a fibroma of tendon sheath as an encapsulated tumour composed of tightly packed spindle cells surrounded by collagen fibres.From 1936 to 1979 no additional cases of fibroma of tendon sheath were reported in the literature until Chung and Enzinger4 described the clinical, macroscopic and light microscopical characteristics of this tumour. They described a well circumscribed often lobulated tumour which was usually attached to tendon or tendon sheath. Microscopically there was dense fibrocollagenous tissue containing usually Accepted for publication 9 December 1981 spindle but sometimes stellate cells and frequently bearing dilated or slit-like vascular channels some of which resembled tenosynovial spaces. In the last few years we have had experience of nine cases of tendon sheath lesions which fulfil the diagnostic criteria of fibroma as laid down by Chung and Enzinger.Our experience with these lesions is reported here in view of the fact that the majority were not initially recognised as fibromas and that electron microscopical studies were performed in two cases. Material and methodsAll tendon sheath lesions accessioned to the Division of Tissue Pathology o...

No abstract

We describe the pathological findings in a case of tracheopathia osteoplastica (TPO) of minimal extent. Although described clinically such minimal lesions have not been previously studied pathologically. Our observations lend strong support to the view-point that the nodules of TPO develop as ecchondroses of the tracheal cartilage rings. It is anticipated that TPO of minimal extent will be increasingly identified clinically and diagnosed on biopsy specimens.

No abstract

No abstract