P.R. Millard

Granular cell tumours revisited. An immunohistological and ultrastructural study.

Twenty‐five granular cell tumours were stained with a panel of antibodies to histiocytic, muscle, neural, neural crest, epithelial and endothelial markers. Electron microscopy was also performed in six cases. Twenty‐four of the cases were similar morphologically and immunocytochemically. One case with features of an endothelial origin is described. The present study strongly supports the viewpoint that granular cell tumours are a distinct entity rather than being the common appearance of a group of lesions of differing histogenesis. Origin from a neural crest‐derived peripheral nerve‐related cell is favoured.

The predictive value of histological classification into degrees of differentiation of squamous cell carcinoma of the larynx and hypopharynx compared with the survival of patients

In the course of running two clinical trials between 1966 and 1985, data became available for 1315 patients, 713 in the first trial and 602 patients in the second trial, which has allowed comparison between histological findings in laryngeal and hypopharyngeal carcinoma, the observed survival and the tumour‐free rates for these patients who were followed for up to 10 years. Extensive histopathology reviews have revealed over 98% agreement on tumour cell type between the initial report and that of the reviewer. Highly significant differences have been found for squamous cell carcinoma between the observed survival and the tumour‐free rates for patients with well‐differentiated and with anaplastic lesions. There was a statistically significant greater proportion of patients with well‐differentiated tumours at larynx sites and in stage 1 when compared with patients with anaplastic tumours, but even when this was taken into account, multivariate analyses showed that tumour grading still made an independent significant contribution to the prediction of prognosis. For squamous cell carcinoma only very simple and rapidly assessed histopathological features need to be identified to classify tumours into the two grades employed in this study. The analyses have confirmed the prognostic significance of tumour grading in squamous cell carcinoma in the larynx and hypopharynx.

Immunohistochemical study of mammary and extra-mammary Paget's disease.

Paraffin sections of 13 cases of Pagets disease (six mammary and seven extramammary) were investigated with mono‐ and polyclonal anti‐carcinoembryonic antigen (CEA) and with monoclonal anti‐human milk fat globule membrane antigen (HMFG). One of these cases was also analysed in cryostat sections with monoclonal anti‐cytokeratin and anti‐keratin. Three immunohistochemical labelling patterns were identified: (1) All six cases of mammary Pagets disease were positive for anti‐HMFG and negative with monoclonal anti‐CEA (although they stained to a variable degree with polyclonal anti‐CEA). (2) Two cases of extra‐mammary Pagets disease (both anal location) were positive with monoclonal anti‐CEA and only weakly stained for HMFG suggesting epidermal spread from a colo‐rectal carcinoma. (3) The other five cases of extra‐mammary Pagets disease were negative or weakly stained for CEA and positive for HMFG. We speculate that this group of cases represents epidermotropic eccrine carcinoma. The immunohistochemical use of monoclonal anti‐HMFG and ‐CEA is helpful in the diagnosis of Pagets disease; moreover it gives information about the origin of the primary tumour.

The 'dirty neck'--a reticulate pigmentation in atopics.

Reticulate pigmentation of the neck is seen in some subjects with atopic eczema. It involves the anterior or antero‐lateral aspects. It is often interpreted as an unwashed appearance and we have called it the ‘Dirty Neck’. Two patterns have emerged. One is found in mildly eczematous, young patients who have a marked increase in pigment during the summer months; it may be confluent in some parts and reticulate in others. The second pattern is a feature of severe atopic eczema, develops after puberty and shows little seasonal variation. Neither pattern is necessarily associated with eczema of the affected area. The morphological and histological characteristics of the ‘Dirty Neck’ are described and possible aetiologies discussed. Distinctions are drawn from ichthyotic ‘dirty necks’ and other types of reticulate pigmentations.

Reactive perforating collagenosis: light, ultrastructural and immunohistological studies.

Reactive perforating collagenosis is an uncommon disorder and few accounts refer to ultrastructural features. This report includes a study by light and transmission electron microscopy of serially sectioned biopsies from early lesions in two patients. Immunohistological investigations utilizing antibodies to basement membrane, laminin, collagen and cytokeratin were also done. Collagen and elastin were demonstrated within the centre of the lesions and there was a defect in the basal lamina at the base of the lesion. The collagen, cytokeratin and the basal lamina in the lesions were antigenically similar to those in the surrounding normal skin. These results are compared with previous findings and discussed in the light of the current views on the pathogenesis of this disorder.

Chrysiasis: transmission electron microscopy, laser microprobe mass spectrometry and epipolarized light as adjuncts to diagnosis

Two patients receiving gold therapy for rheumatoid arthritis developed skin pigmentation, chrysiasis, which in one appeared 4 months after cessation of the therapy. The diagnosis was confirmed by transmission electron microscopy and mass spectrometry laser microprobe analysis of paraffin sections and its extent demonstrated by epipolarized light. The condition is poorly reported and clinically may be confused with silver and mercury impregnation. Tissue diagnosis requires ancillary methods and of these, transmission electron microscopy and laser microprobe mass spectrometry are excellent examples. The transmission electron microscopy findings differ from previous reports and raise doubts on the hypothesis on the role of the skin in gold excretion. Because of the renewed interest in crysotherapy and the latent period that can separate this from chrysiasis, an increase in chrysiasis and the need for its diagnosis can be anticipated.

Dermatitis repens, Lapiere and generalized pustular psoriasis

The presence of subcorneal pustules in a solitary, indolent, crusted plaque, or in erythema annulare‐like lesions with a trailing scale, is evidence of atypical psoriasis. When these lesions appear late in life there is a significant risk of generalized pustular psoriasis with a poor prognosis. A case is presented in whom both of these atypical forms occurred and who developed severe generalized disease. Clinical and histological features are described.

Oncocytoma of the stomach: a case report

An example of an oncocytoma in the wall of the stomach is reported. The diagnosis was made following ultrastructural studies and must be considered in the differential diagnosis of gastric tumours and especially of atypical leiomyomas and granular cell tumours.

Giant lichenification of the scalp

Summary Lichenification is characterized clinically by thickening of areas of skin as a result of the itch–scratch cycle and therefore is seen in conditions associated with chronic pruritus. The characteristic feature of giant lichenification is the occurrence of tumour‐like growths with a warty cribriform surface. We describe a renal transplant patient presenting with giant lichenification of the scalp following an attack of herpes zoster at the same site. Chronic pruritus following scalp dysaethesia secondary to herpes zoster was considered the most likely explanation for the occurrence of these lesions.

Atypical malignant melanoma of the nail apparatus

Malignant melanoma of the nail is a serious disease with a five year survival rate of between 21% (Booher & Pack, 1957) and 50% (Graham, 1973). The diagnosis of atypical cases ultimately depends on interpreting histological material. We report here a case in which two initial biopsies of the affected nail failed to show malignant melanoma. The diagnosis was eventually made by formal longitudinal nail biopsy including matrix tissue proximal to the dystrophic area, and examination of sections cut at several levels.