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Biomedical subjects

N Kirkham

Publications and source records attributed to N Kirkham.

At least 19 recordsLinked to original sources
PubMed2002

U.K. guidelines for the management of cutaneous melanoma.

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.

Biopsy↗
PubMed2002

UK guidelines for the management of cutaneous melanoma.

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 UK, they are subject to dual publication in the British Journal of Dermatology and the British Journal of Plastic Surgery.

Biopsy↗
PubMed2000

What criteria reliably distinguish melanoma from benign melanocytic lesions?

The differential diagnosis of melanocytic lesions is fraught with difficulty and a common source of litigation either if a lesion misreported as 'benign' recurs locally or re-presents with nodal metastases or if an atypical naevus is called 'malignant' leading to a cosmetically unsatisfactory wider resection, unwarranted anxiety about prognosis and adverse life insurance prospects. Several authors have claimed that there are valid morphological criteria which, alone or in combination, enable reliable distinction between benign and malignant melanocytic lesions. Others question these criteria and, doubting the extent to which unequivocal diagnoses can be rendered in all cases, believe that the diagnosis is purely subjective and that most diagnostic errors are non-negligent. To address these issues, expert opinions were commissioned from three sets of authors. Okun, Edelstein & Kasznica emphasize that a significant minority of melanocytic lesions are so borderline morphologically that diagnostic uncertainty is allowable and that such uncertainty can be handled responsibly. Kirkham, in favouring the methodical use of criteria, concedes that they are 'largely opinion-based rather than evidence-based, but do go beyond mere subjective pattern analysis'. In agreement with Okun and his colleagues. Slater emphasises that no single feature is reliable by itself and that all aspects, including clinical details, should be interpreted together; he has no hesitation in reporting the diagnosis as 'uncertain' in doubtful cases. In the absence of a specific marker pathognomonic of melanocytic malignancy, the diagnosis will continue to rely on the judicious application of morphological criteria with a small proportion of elusive cases in which diagnostic uncertainty should not be concealed.

Biomarkers, Tumor↗
PubMed1997

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.

Hair Follicle↗
PubMed1997

The value of the polymerase chain reaction in the diagnosis of cutaneous T-cell infiltrates.

The distinction between reactive and neoplastic cutaneous T-cell infiltrates is difficult and requires good clinicopathologic correlation. Many cases manifest changes that are at the borderline between the two. The polymerase chain reaction (PCR) has been reported to detect monoclonality in 52-90% of cutaneous T-cell lymphomas and may be of use in the diagnosis of histologically borderline lesions. We have investigated the use of PCR in a series of borderline lesions including borderline biopsy samples from patients who subsequently developed cutaneous lymphoma. PCR amplification of T-cell receptor (TCR)-gamma chain gene was performed on formalin-fixed, paraffin-embedded tissue from 27 cases of clinically and histologically typical mycosis fungoides (MF), 22 borderline biopsy samples from 10 patients who subsequently developed MF (pre-MF), 32 clinically suspicious, histologically borderline lesions, and 31 cases of chronic dermatitis. Monoclonality was demonstrated in 16 of 27 (59%) cases of MF, 10 of 22 (50%) pre-MF biopsy samples (six of 10 patients), and six of 32 (19%) borderline biopsy samples. The same size monoclonal band was detected in pre-MF biopsy samples from six of seven patients in which a band was demonstrated in the diagnostic MF biopsy. Sequencing confirmed that the MF biopsy sample and the pre-MF biopsy sample contained the same clone. The 31 dermatitis cases gave rise to polyclonal PCR products. Monoclonality can be demonstrated using PCR in 59% of MF cases, which is comparable with other T-cell lymphomas and in up to 50% of borderline biopsy samples in patients who later develop lymphoma. Detection of T-cell monoclonality by PCR is strong evidence of an established or evolving cutaneous T-cell lymphoma.

Base Sequence↗
PubMed1994

The use of cytology in the diagnosis of basal cell carcinoma.

Two hundred and forty patients with basal cell carcinomas (BCCs) on the head or neck were studied. Scrapings of the lesions were taken for cytological examination, and a 3-mm punch biopsy was performed for histopathological study. The accuracy of diagnosis by each method was compared. Both methods confirmed the clinical diagnosis in 226 cases, and both were negative in 10 cases. Cytopathology gave one false negative result (0.42%), and histopathology gave two false negative results (0.83%). Cytopathology gave one false positive result (0.42%), and histopathology did not produce any false positive results. We conclude that cytological examination of skin scrapings from suspected BCCs is a rapid and reliable method of diagnosis.

Basal Cell Carcinoma↗
PubMed1993

Whole chromosome 17 loss in ovarian cancer.

Chromosomal deletions, associated with the loss of normal function of tumour suppressor genes, have been identified in a variety of both familial and sporadic human cancers. Although the molecular pathology of ovarian cancer is not understood, several studies have reported deletions in chromosome 17 in ovarian tumours. We have used 13 restriction site polymorphic, microsatellite, and variable number tandem repeat markers to make a detailed analysis of chromosome 17 deletions in 12 benign and 19 malignant ovarian tumours. Two benign and 11 malignant tumours were informative for at least one marker on each arm of the chromosome. Loss of heterozygosity (LOH) was detected in both arms (by all informative markers) in 5 malignant tumours from four women (three with the disease at FIGO stage Ia). In a further bilateral ovarian tumour a partial LOH affecting 17q22-q25 was present in one ovary only. By contrast to a number of previous studies, none of the 19 malignant and 12 benign tumours showed ERBB2 (17q12-22) amplification. The data presented show that the loss of a whole copy of chromosome 17 is a frequent and relatively early event in the development of some ovarian cancers. This suggests the possible involvement of multiple chromosome 17 loci in the pathogenesis of ovarian cancer. Equally plausible is that the loss of a whole chromosome copy could be the product of chromosomal instabilities induced by loss of the normal allele of tumour suppressors, such as TP53, located on this chromosome.

Adenofibroma↗
PubMed1993

Gold in the dermis following chrysotherapy: histopathology and microanalysis.

Paraffin-embedded sections of skin from patients with rheumatoid arthritis treated with gold who had developed skin rashes were examined by light microscopy and scanning electronmicroscopy with microanalysis. Sparse, small, brown or black granules in plump, often elongated cells in the dermis were shown to contain gold by energy dispersive X-ray microanalysis. These cells expressed some macrophage markers. The amount of gold present showed some correlation with the total gold dose. Gold was not confined to lesional skin. In one case where uninvolved skin was examined, more gold was found there than in lesional skin.

Aged↗
PubMed1992

A computer-based decision support system for diagnostic histopathology of the breast.

Accurate histological diagnosis of breast lesions is essential for the appropriate management of the patient. However, the technique of histological typing is problematic due to the large number of histological patterns, often of a complex and variable nature, which occur in breast disease. The introduction of the Breast Screening Programme has increased the burden on pathologists, and emphasised the need for training. Problems arise because mammographic screening detects a greater proportion of special histological types, with their attendant difficulties of identification, when compared to clinically palpable lesions. A computer-based decision support tool has been developed to assist pathologists in the histological diagnosis of breast disease. Unlike conventional expert systems, which seek to recreate the problem-solving processes of an expert, this system has been designed to act as an intelligent assistant to the pathologist. The system represents knowledge in the form of 'disease profiles', and utilises a novel inference model based upon the mathematical technique of hypergraphs. Initial trials with this system have demonstrated that a high level of diagnostic accuracy can be achieved.

Breast Diseases↗
PubMed1992

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.

Child↗