N. Kirkham

U.K. guidelines for the management of cutaneous melanoma

Summary  These guidelines for management of cutaneous melanoma present evidence‐based guidance for treatment, with identification of the strength of evidence available at the time of preparation of the guidelines, and a brief overview of epidemiological aspects, diagnosis and investigation. To reflect the collaborative process for the U.K., they are subject to dual publication in the British Journal of Dermatology and the British Journal of Plastic Surgery.1

MALIGNANT HISTIOCYTOSIS OF THE INTESTINE: A T-CELL LYMPHOMA

Malignant lymphoma complicating coeliac disease has been characterised on morphological and immunocytochemical grounds as malignant histiocytosis of the intestine (MHI). Fresh tissue from four cases of MHI was studied by means of a panel of monoclonal antibodies; in three cases tumour DNA was studied for immunoglobulin and T-cell receptor (TCR) gene rearrangement. Immunocytochemistry showed a T-cell phenotype in all four cases, confirmed by the demonstration of a rearranged TCR beta-chain gene in the three cases studied. Lymphoma complicating coeliac disease thus appears to be of T-cell, rather than histiocyte, origin.

Monoclonal antibody MAC 387 recognizes a myelomonocytic antigen shared by epithelial cells in inflammatory skin diseases

The monoclonal antibody MAC 387 recognizes an antigen expressed by human macrophages and granulocytes. Normal epidermis does not react with the antibody, but the inflamed epidermis may react. In this immunocytochemical study we have investigated the intracytoplasmic expression of the MAC 387 antigen in biopsies of a variety of skin disorders. In lichen planus the basal cells were usually negative, whilst suprabasal cells were positive. In the majority of other inflammatory dermatoses studied, there was positive staining of basal and suprabasal cells. A parallel frozen‐ and paraffin‐section study of biopsies of cutaneous T‐cell lymphomas and inflammatory conditions failed to demonstrate HLA Class 11 expression in the cytoplasm of keratinocytes. Expression of the MAC 387 antigen in the epidermis is directly associated with cell‐mediated activity in the papillary dermis, but is not related to HLA Class II expression.

An immunocytochemical study of MHC class I expression on human Langerhans cells and melanocytes

Classical MHC class I glycoproteins (HLA‐A, B, and C) present endogenous cytosolic peptide antigen fragments to CD8‐positive T‐cells. CD8‐positive T‐cell recognition and destruction of virus‐infected cells are dependent on adequate cellular MHC class I expression. Constitutive MHC class I expression is ubiquitous, but known to be deficient on specific differentiated cell types which include hepatocytes, neurones, chondrocytes and myocytes. Although enabling assessment of MHC class I expression on individual cells, limitations of immunocytochemistry were encountered with this assessment on Langerhans cells and melanocytes. These dispersed intraepidermal cells were obscured by adjacent keratinocytes in sections immunostained for MHC class I glycoproteins. Initiatives designed to resolve the issue have included immunoelectron microscopy, cell culture techniques, and animal bone marrow chimera models. Despite the elegance of these techniques, the issue of MHC class I expression on Langerhans cells and melanocytes remains unresolved. In this immunocytochemical study, an alternative strategy was based upon the recognized deficiency of epithelial MHC class I expression within pilosebaceous adnexal units. Langerhans cells and melanocytes were therefore studied within this microenvironment of deficient MHC class I expression, using monomorphic and polymorphic MHC markers. Langerhans cells and melanocytes were demonstrated within pilosebaceous units of scalp skin by immunocytochemistry. Differentiation markers OKT6 (CD1a) and TMH1 defined Langerhans cells and melanocytes, respectively. Monomorphic MHC markers W6/32 and TAL IB5 defined invariant epitopes of HLA class I and II, respectively. Polymorphic MHC class I markers defined the HLA‐Bw4 and HLA‐Bw6 supertypic determinants. Constitutive MHC class I expression was shown to be deficient on Langerhans cells and melanocytes.

Malignant parotid salivary gland peripheral nerve sheath tumour in a twelve-year-old girl

A case of a malignant parotid salivary gland nerve sheath tumour is reported in a 12-year-old girl who developed a right parotid mass. Initial incisional biopsy showed a tumour with a mesenchymal spindle cell appearance. Immunohistochemical studies showed positive staining of tumour cells for vimentin and focally for S-100 protein. These features together with ultrastructural evidence of basal lamina material suggested that the tumour was of nerve sheath origin. After subtotal parotidectomy the tumour metastasised to cervical lymph node and lung. There was evidence of a partial response to chemotherapy. A detailed illustrated histopathological description of the tumour is given.

Object-oriented design and programming in medical decision support

The concept of object-oriented design and programming has recently received a great deal of attention from the software engineering community. This paper highlights the realisable benefits of using the object-oriented approach in the design and development of clinical decision support systems. These systems seek to build a computational model of some problem domain and therefore tend to be exploratory in nature. Conventional procedural design techniques do not support either the process of model building or rapid prototyping. The central concepts of the object-oriented paradigm are introduced, namely encapsulation, inheritance and polymorphism, and their use illustrated in a case study, taken from the domain of breast histopathology. In particular, the dual roles of inheritance in object-oriented programming are examined, i.e., inheritance as a conceptual modelling tool and inheritance as a code reuse mechanism. It is argued that the use of the former is not entirely intuitive and may be difficult to incorporate into the design process. However, inheritance as a means of optimising code reuse offers substantial technical benefits.

Malakoplakia of the pelvic peritoneum in pregnancy. Case report

Case report The patient was a 30-year old Mauritian woman, resident in England for 10 years. In 1978 she had an emergency caesarean section, in labour, for fetal distress. No intra-abdominal abnormality was noted. In 1981 an attack of lower abdominal pain led t o a laparotomy and appendicectomy. The fallopian tubes appeared mildly inflamed, but were not biopsied. The appendix showed mild serosal inflammation but no evidence of malakoplakia. In 1Y82 she aborted at 11 weeks gestation; thc curcttings did not show malakoplakia. In 1983 she became pregnant for the third time. At 20 weeks gestation she was admitted complaining of a sudden attack of suprapubic and bilateral loin pain, together with frequency, dysuria, diarrhoea and vomiting. She was apyrexial and distressed, with tenderness and guarding in the lower abdomen and tenderness in the right renal angle. A mid-stream urine culture (MSU) revealed a significant (>lo5 bacteriaiml) growth of coliform bacteria; the infection responded clinically to ampicillin. During the 33rd week of pregnancy she was re-admitted with generalized abdominal pain mainly localized in the epigastrium and right iliac fossa. There were no associated urinary symptoms. A further MSU was sterile. A cystoscopy was not performed. The pain settled without further treatment. The pregnancy then proceeded uneventfully until 39 weeks when an elective caesarean section was performed in view of her previous section and a narrow funnel-shaped pelvis shown on X-ray pelvimetry. All of the pelvic organs were

Virilizing ovarian serous cystadenoma. Case report

An 80-year-old woman consulted a dermatologist because over the previous 17 years she had developed diffuse scalp hair loss and hirsutism over the chest. She was obese, with a markedly elevated free serum testosterone level of 58•5 pmol/l. A pelvic ultrasound scan revealed a left ovarian cyst with no solid areas. The left ovarian tumour was a benign serous cystadenoma with a thin layer of luteinized cells in the cyst wall

Colonic Angiodysplasia and AL Amyloidosis in a Patient with Lower Intestinal Bleeding

An episode of lower gastro-intestinal haemorrhage in a patient, dialysed for chronic renal failure secondary to systemic AL amyloidosis, is described. The bleeding was due to angiodysplasia, but the presence of colonic amyloidosis complicated the diagnosis. The difficulties of diagnosing amyloidosis and angiodysplasia of the colon are discussed and other causes of colonic haemorrhage in patients with chronic renal failure and systemic amyloidosis are reviewed. The coexistence of amyloidosis and angiodysplasia of the colon has not previously been reported.

Differential Diagnosis in Breast Histopathology

The problem of accuracy and consistency in the histological typing of breast disease has been addressed by the development of a decision support system, which assists the pathologist through the identification of important differential tests and ranking of competing diagnoses. The inference model embodied within the system is based upon the notion of a vertex covering of a hypergraph and the Kemeny social choice function. The hypergraph model is in sense ‘dual’ to that of the set covering model developed by Reggia and has several advantages over the set covering approach. Initial trials with the system have demonstrated the potential of the hypergraph model.