PubMed Health⌕ Search

Biomedical subjects

H S Rigby

Publications and source records attributed to H S Rigby.

At least 19 recordsLinked to original sources
PubMed2006

Multiple malignant melanomas in association with neurofibromatosis type 1.

We present a case of multiple primary malignant melanomata occurring over a six year period in a 63-year-old Caucasian man with neurofibromatosis type 1. There is doubt regarding a definite association between these two diseases despite a number of case reports and clear, potential pathological mechanisms. This case not only strengthens support for an association but also highlights the great difficulties that arise in the management of cutaneous melanomata in patients with neurofibromatosis.

Humans↗
PubMed2001

Is routine histological reporting of doughnuts justified after anterior resection for colorectal cancer?

OBJECTIVE: 'Doughnuts' of colonic tissue which remain on a circular stapler after firing are routinely examined histologically. However, Royal College of Pathologists' guidelines state that this is not necessary. The aim of this study was to examine current practice among pathologists in one region in the UK and to determine the incidence of clinically significant pathology within colonic doughnuts. METHODS: Current practice in all pathology Departments within the South-west Region was examined and 100 doughnuts from anterior resection specimens were reviewed for the presence of abnormal pathology. RESULTS: Practice varied between hospitals with only 15% following guidelines for examination of doughnuts and 38% following guidelines for reporting of resection margins. Review of pathology specimens demonstrated no incidence of colonic adenocarcinoma in a doughnut. Benign pathology was present in 9% and dysplasia in 3% but in no case was patient management altered as a result of the pathology report. CONCLUSION: Application of recommended guidelines is inconsistent. We have demonstrated a low incidence of clinically significant pathology in doughnuts and more economical guidelines could therefore be safely applied without detriment to patient care.

Journal Article↗
PubMed2001

A 6 year prospective analysis of the diagnosis of malignant melanoma in a pigmented-lesion clinic: even the experts miss malignant melanomas, but not often.

We investigated whether the pigmented-lesion clinic (PLC) run by the Department of Plastic and Reconstructive Surgery at Frenchay Hospital was effective in making and excluding the diagnosis of malignant melanoma, by looking at the pattern of referrals over time, the number of melanomas excised and melanomas in which the diagnosis was delayed or missed. We also investigated whether the PLC was having an effect on the thicknesses of melanomas excised. All 9968 patients attending the PLC between 1 January 1993 and 31 December 1998 were included in the study and 586 malignant melanomas were diagnosed; 24.7% of excisions led to the diagnosis of malignant melanoma. Seven invasive melanomas and two lentigo malignas were missed. There was one histological false negative. The PLC has a sensitivity of 98.5% and specificity of 89.2% for the diagnosis of melanoma; the negative predictive value is 99.9%. The PLC is effective in rapidly making or excluding the diagnosis of malignant melanoma, but has had no effect on the average thickness of melanomas excised over the 6 year study period.

Adult↗
PubMed1999

Juvenile xanthogranuloma variant: a clinicopathological case report and review of the literature.

Juvenile xanthogranuloma is a relatively rare cutaneous lesion. In order to make an early diagnosis and be alert to the possibility of visceral complications and associated medical conditions, plastic surgeons should be aware of the entity. The classic presentation is that of successive eruptions in the head, neck and upper trunk of initially red papules or nodules which later become yellow and finally brown flattened plaques or macules. This report is of an unusual variant with atypical histology including frequent mitoses and a lack of Touton giant cells.

Diagnosis, Differential↗
PubMed1998

Prognostic significance of allelic losses in primary melanoma.

Loss of genetic material, including loss of loci on chromosome arms 6q, 9p, and 10q, occurs frequently in cutaneous melanoma but infrequently in benign melanocytic nevi or other melanocytic lesions, suggesting that these genetic alterations are important in the development and progression of melanoma. To examine whether allelic loss is of prognostic importance in melanoma, disease-free survival was related to loss of heterozygosity on 6q, 9p and 10q in 83 individuals with sporadic primary cutaneous melanoma. Loss of chromosome arms 6q and 10q were each significantly associated with a poorer clinical outcome (P=0.013 and P=0.001 respectively). In a subgroup of 41 subjects whose primary tumours were allelotyped, the fractional allelic loss (FAL) at 39 autosomal arms also significantly correlated with disease-free survival (P=0.013), with an increase in FAL associated with a poorer outcome; this association remained significant when controlled for tumour thickness (P=0.035). In addition, a greater proportion of cells were immunopositive for Ki67 antigen, p53 and p21WAF1 protein in the primary melanomas than in the benign melanocytic nevi, however, only p53 over-expression was significantly associated with improved survival (P=0.041).

Alleles↗
PubMed1997

Sub-lethal effects of exposing the human melanoma cell line SKmel-23 to 532 nm laser light.

The human melanoma cell line SKmel-23 has been used to investigate the sub-lethal damage that can occur as a result of exposing melanin containing cells to light (532 nm) from a frequency doubled Q-switched (Nd:YAG) laser. A dose response curve was obtained, which indicates that at energy levels of 0.6 J/cm2 and below no effect on either the viability or growth rate of the cell line was observed. Above this, cells rapidly died and at an energy level of 2.0 J/cm2, only approximately 15% of cells survived. This contrasts with the effects on the G361 melanoma line, which contains far less melanosomes, as an LD50 for this cell line was approximately 5.5 J/cm2. Exposing SKmel-23 cells to 0.4 J/cm2 of 532 nm light results in a diminution of the number of melanosomes within cells as well as a marked decrease in melanin content, as determined by spectrophotometric assay and electron microscopy. Using the reverse transcriptase polymerase chain reaction technique, the reduction in melanin content of the cells was accompanied by a selective decrease in mRNA coding for tyrosinase, the first enzyme in the biosynthetic pathway for melanin. No decrease in the mRNA coding for the GAPDH protein was observed. Our finding has implications for understanding the control processes that regulate the melanin content of cells and suggests that the model described can be used to further investigate changes that may occur in cells as a result of their exposure to sub-lethal levels of laser light.

Cell Division↗
PubMed1997

Cutaneous malignant melanoma in the young.

Between the years 1967 and 1993, 3246 patients were diagnosed with malignant melanoma at Frenchay Hospital, Bristol. This paper reports 47 patients, 21 years of age or under, including 10 preadolescent cases under 14 years of age. It represents a further follow-up of a cohort originally published from this centre in 1986 in addition to 18 new cases. Most (89%) of the lesions occurred on the trunk and extremities, with females showing a predominance of lesions on the lower limbs. 83% of the melanomas were of the superficial spreading type: 72% invaded to Clark level III and IV. Thickness ranged from 0.29 mm to 50.00 mm (median 1.20 mm). Ulceration was present in 17% of cases and 32% of melanomas arose within a pre-existing small congenital melanocytic naevus. Overall 5-year survival was 81%, with a mean follow-up of 8.5 years. Ulceration and tumour thickness of greater than 1.5 mm were associated with a poor prognosis.

Adolescent↗
PubMed1996

Recurrence of thin melanoma: how effective is follow-up?

In order to assess the benefit to patients with thin malignant melanoma (< 0.76 mm) of a 5-year clinical follow-up programme, we have studied 602 patients with a minimum time from primary surgery of 5 years. Tumour recurrence occurred in 24 patients (4% of all patients) but only five surgically treatable recurrences (< 1% of all patients) occurred within the 5-year period following primary surgery. After 5 years there were four surgically treatable recurrences, but their prognosis was generally poor. The remaining cases of tumour recurrence were not surgically treatable. In the face of an increasing incidence of melanoma, and the accompanying increase in demand for surgical treatment and outpatient review, we question the need for prolonged hospital follow-up of thin melanoma.

Adult↗
PubMed1996

Agminate Spitz naevi occurring in an adult after the excision of a solitary Spitz naevus--report of a case and review of the literature.

We describe a 21-year-old female who presented with four agminate Spitz naevi close to the scar from a previously excised solitary Spitz naevus, and review the literature since 1987 on widespread and agminate Spitz naevi. Spitz naevi usually present as solitary firm red or brown papular lesions. Agminate Spitz naevi are unusual and they have been reported mainly in children. It is uncommon for Spitz naevi to recur after surgery and far more unusual for a recurrence to occur in an agminate form. Such lesions may mimic multiple satellite and in-transit metastases which can occur in malignant melanoma, and close follow up of any new lesions occurring in this case is intended.

Adult↗
PubMed1995

A pigmented lesion clinic: analysis of the first year's 1055 patients.

The Pigmented Lesion Clinic (PLC) at Frenchay Hospital was started in January 1993 to deal rapidly and effectively with a growing number of referrals of suspicious pigmented lesions. Its objectives were to offer expert assessment and either reassurance or excision at the first PLC following referral by the patient's general practitioner. During 1993, 1055 patients were seen in 37 PLCs and 357 excision biopsies were performed. We have compared the Breslow thicknesses of malignant melanomas diagnosed from the PLCs with those of all other (non-PLC) malignant melanomas referred to our unit over the same period. We discuss the development and results of the first year of our PLC and the advantages it confers.

Cancer Care Facilities↗
PubMed1994

Unusual pulmonary complication of ulcerative colitis with a rapid response to corticosteroids: case report.

Extraintestinal features of ulcerative colitis are well recognised. Pulmonary complications include pulmonary vasculitis, fibrosing alveolitis, asthma, and chronic bronchial suppuration. A case is described of a patient with longstanding quiescent ulcerative colitis who developed a life threatening pulmonary complication, which is extremely sensitive to corticosteroid treatment.

Adult↗
PubMed1993

Cutaneous melanoma: pathological certainties and uncertainties.

A historical review is given of the role of histopathology as a prognostic guide to the behaviour of cutaneous melanomas. Problems in the assessment of some of the current parameters are outlined in an attempt to explain the difficulties faced by histopathologists with some types of melanoma.

Biopsy↗
PubMed1993

The role of fixator frame stiffness in the control of fracture healing. An experimental study.

External skeletal fixation is used widely in the management of fractures. Frame configuration is known to affect frame stiffness and, thereby, the local mechanical environment at the fracture site. In previous investigations of the influence of mechanical conditions upon fracture healing, the frames have always been applied so that they influence the biological environment in different ways. As a result, the influence of stiffness, per se, could not be studied as a single variable, and its effect on the repair process remains unclear. In this study, using a standard osteotomy of the ovine tibia, stabilised by an external skeletal fixator, the local mechanical environment was altered solely by increasing the 'offset' distance between the bone and the fixator frame. The biological conditions at the fracture remained identical in both groups. Increasing the frame stiffness by 40%, brought about by reducing the offset distance of the fixator bar by 10 mm, caused a significant reduction in the rate of healing. In addition, the frame stiffness influenced the ground reaction force with greater weight-bearing in the initial stages in the more rigid group, but despite this, the resultant interfragmentary displacement in this group appeared to be insufficient to stimulate fracture healing. This work emphasises the importance of the local mechanical environment on the process of fracture healing. It also demonstrates the value of in vivo assessment of fracture stiffness as a means of monitoring mechanical events during fracture healing.

Animals↗
PubMed1993

Giant primary mucinous sweat gland carcinoma of the scalp.

Primary mucinous sweat gland carcinoma is a rare tumour which usually behaves in a relatively benign manner. This is illustrated by the massive proportions which this tumour reached in the case described, without evidence of metastases.

Adenocarcinoma, Mucinous↗
PubMed1991

Colour perception in pathologists: the Farnsworth-Munsell 100-hue test.

The value of many histological stains depends on the ability of the observer to differentiate colour. This ability was assessed in 30 histopathologists and cytopathologists of varying experience using the Farnsworth-Munsell 100-hue test. As a group, the pathologists performed better than a reference population. Twenty eight subjects showed a wide ranging ability to differentiate colour: none was colour blind. Three of the 30 pathologists, however, fell below the twentieth centile for normal subjects and only one was aware of this deficiency! They may unknowingly misinterpret subtle stains. Two of these three had specific and major defects which could affect their ability to interpret a wide range of less subtle stains. Those with the poorest colour discrimination were not those with the least experience of microscopy. Pathologists should be apprised of the importance of their ability to discriminate colour, and that formal colour vision testing of prospective histopathologists may be appropriate.

Adult↗