Proffered Papers 10.30–11.15 Monday 15 September 2003 3 5 year outcome of women with borderline and mild dyskaryosis smears 3 5 year outcome of women with borderline and mild dyskaryosis smears

Aims

• 1 To identify the outcome status of women with borderline and mild dyskaryosis smears.
• 2 To determine whether the presence or absence of koilocytosis influences the outcome status.
• 3 To identify the proportion of women with borderline smears showing koilocytosis.

Materials and methods Borderline and mild dyskaryosis cervical smears diagnosed during January to March 1997 were identified from the laboratory database. Each slide was reviewed by two researchers independently, who then agreed a final consensus diagnosis. All slides were classified according to the presence or absence of koilocytosis. Slides were excluded from the study if the review diagnosis was negative, inadequate or high‐grade dyskaryosis. The outcome status was classified according to the worst lesion identified histologically and/or cytologically during the 5‐year follow‐up period. Results 1974 women were identified with borderline or mild dyskaryosis cervical smears of which 1597 were included in the study. Table 1 shows the outcome status of these women.

Table 1. . The outcome status of these women

Morphometric and population genetic analyses elucidate the origin,evolutionary significance and conservation implications of Orchis × angusticruris (O. purpurea × O. simia), a hybrid orchid new to Britain

We report the first confirmed occurrence in Britain of Orchis × angusticruris Franch. ex Rouy, a hybrid between two closely related orchid species of anthropomorphic Orchis (O. purpurea Huds. × O. simia Lam.) that hybridize frequently in Continental Europe. Seven individual hybrids, most likely F1 plants representing a single interspecific pollination event, first flowered with both parents in May 2006 at a nature reserve in the Chiltern Hills near Goring, Oxfordshire. Univariate and multivariate morphometric analyses (43 characters plus 12 indices), internal transcribed spacer sequencing, plastid microsatellites and amplified fragment length polymorphism (AFLP) analyses together readily separate the parents and confirm that O. purpurea was the ovule parent and O. simia the pollen parent, presumably reflecting the greater frequency and/or later flowering period of the latter at the site. This study reinforces a more general observation that, in most orchids, the ovule parent contributes substantially more to the hybrid phenotype than does the pollen parent, perhaps reflecting cytoplasmic inheritance. In contrast, the hybrids are placed closer to O. simia than to O. purpurea in the AFLP tree. Apparently recent arrivals, the few O. purpurea plants at Goring contrast genetically with the two other small populations of this species known in the Chilterns, but rather are consistent with relatively uncommon Continental populations. This suggests that the plants may have been deliberately introduced at Goring by man, although transport from the Continent in high‐level air currents cannot be ruled out. The Goring population of O. simia is likely to have become genetically impoverished through (1) preferential removal of many relatively fit plants to herbaria in the 19^th century and/or (2) a catastrophic population crash in the first half of the 20^th century. However, both our re‐examination of herbarium specimens and our population genetic data indicate past hybridization among anthropomorphic Orchis species occurring naturally in the Chilterns. Thus, we tentatively recommend retention of the hybrid plants at Goring, despite their likely anthropogenic origin from Continental material and the partial viability of their pollen and seeds, which offers opportunities for future introgression. Although the Goring hybrids broadly resemble morphologically O. militaris, another anthropomorphic Orchis still found at two Chiltern localities, sufficient morphological and molecular differences were observed to strongly refute our initial hypothesis that O. militaris could have originated through hybridization between ancestors that resembled O. purpurea and O. simia. The comparatively complex genetic properties evident in both O. simia and O. purpurea merit further study. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 157 , 687–711.     

Applying the light : nutrient hypothesis to stream periphyton

1. The light : nutrient hypothesis (LNH) states that algal nutrient content is determined by the balance of light and dissolved nutrients available to algae during growth. Light and phosphorus gradients in both laboratory and natural streams were used to examine the relevance of the LNH to stream periphyton. Controlled gradients of light (12–426 μmol photons m^?2 s^?1) and dissolved reactive phosphorus (DRP, 3–344 μg L^?1) were applied experimentally to large flow‐through laboratory streams, and natural variability in canopy cover and discharge from a wastewater treatment facility created gradients of light (0.4–35 mol photons m^?2 day^?1) and DRP (10–1766 μg L^?1) in a natural stream. 2. Periphyton phosphorus content was strongly influenced by the light and DRP gradients, ranging from 1.8 to 10.7 μg mg AFDM^?1 in the laboratory streams and from 2.3 to 36.9 μg mg AFDM^?1 in the natural stream. Phosphorus content decreased with increasing light and increased with increasing water column phosphorus. The simultaneous effects of light and phosphorus were consistent with the LNH that the balance between light and nutrients determines algal nutrient content. 3. In experiments in the laboratory streams, periphyton phosphorus increased hyperbolically with increasing DRP. Uptake then began levelling off around 50 μg L^?1. 4. The relationship between periphyton phosphorus and the light : phosphorus ratio was highly nonlinear in both the laboratory and natural streams, with phosphorus content declining sharply with initial increases in the light : phosphorus ratio, then leveling off at higher values of the ratio. 5. Although light and DRP both affected periphyton phosphorus content, the effects of DRP were much stronger than those of light in both the laboratory and natural streams. DRP explained substantially more of the overall variability in periphyton phosphorus than did light, and light effects were evident only at lower phosphorus concentrations (≤25 μg L^?1) in the laboratory streams. These results suggest that light has a significant negative effect on the food quality of grazers in streams only under a limited set of conditions.     

Proffered papers 9.30–10.00 Monday 15 September 2003 2 Clinicopathologic significance of the ‘borderline nuclear change – high grade dyskaryosis not excluded’ report

Both the original Bethesda system and the current UK classifications of cervical cytology have proved robust but each has a major weakness in the area of abnormalities of uncertain significance. Cytologists recognize that sometimes it is simply impossible to differentiate between reactive and dyskaryotic material. For this reason, the Australian version of the Bethesda system introduced a new category of ‘high grade inconclusive’ with a recommendation for referral to colposcopy. Approximately 60% of such cases are found to have high grade lesions at colposcopy (Schoolland M, Sterrett G, Knowles S et al.). The present UK system even with the proposed changes requires of the pathologist, a decision as to whether such cases are probably high grade (=a report of moderate dyskaryosis) or not (= a report of borderline). This continues to ignore the fact that sometimes you just cannot tell, even on review. We have taken a consecutive series of 50 referral smears, reported as moderate dyskaryosis, where the histological outcome (by loop cone) is known. These cases were rescreened and then reviewed blind by a pathologist with extensive experience of the Australian NH & MRC modified Bethesda system. On review, the material was reclassified along NH & MRC lines. The results were compared with the biopsy findings in order to determine whether the category of ‘inconclusive’ might be of value in the context of the NHSCSP.     

Carbon : nitrogen stoichiometry in forest ecosystems during stand development

Aim Carbon (C) and nitrogen (N) stoichiometry is a critical indicator of biogeochemical coupling in terrestrial ecosystems. However, our current understanding of C : N stoichiometry is mainly derived from observations across space, and little is known about its dynamics through time. Location Global secondary forests. Methods We examined temporal variations in C : N ratios and scaling relationships between N and C for various ecosystem components (i.e. plant tissue, litter, forest floor and mineral soil) using data extracted from 39 chronosequences in forest ecosystems around the world. Results The C : N ratio in plant tissue, litter, forest floor and mineral soil exhibited large variation across various sequences, with an average of 145.8 ± 9.4 (mean ± SE), 49.9 ± 3.0, 38.2 ± 3.1 and 18.5 ± 0.9, respectively. In most sequences, the plant tissue C : N ratio increased significantly with stand age, while the C : N ratio in litter, forest floor and mineral soil remained relatively constant over the age sequence. N and C scaled isometrically (i.e. the slope of the relationship between log‐transformed N and C is not significantly different from 1.0) in litter, forest floor and mineral soil both within and across sequences, but not in plant tissue either within or across sequences. The C : N ratio was larger in coniferous forests than in broadleaf forests and in temperate forests than in tropical forests. In contrast, the N–C scaling slope did not reveal significant differences either between coniferous and broadleaf forests or between temperate and tropical forests. Main conclusions These results suggest that C and N become decoupled in plants but remain coupled in other ecosystem components during stand development.     

FINES,ORDERS, FEAR . . . AND CONSENT? MEDICAL RESEARCH IN EAST AFRICA,C. 1950s

This article reconstructs the history of medical research in East Africa (Kenya, Tanganyika, Uganda), laying out the lies, rumours, and oppressive techniques that made research such a fraught enterprise during the colonial era. The focus is on the beginning stages of medical research: researchers' arrivals, villagers' responses, the gathering of subjects and consent. New archival and oral sources gathered in East Africa illuminate the research encounter and reintegrate the perspective of villagers cum subjects. Data from the 1950s shows that upon arrival in a village, researchers regularly lied in order to avoid sensitive topics and sidestep potential opposition. Misinformation fuelled villagers' fears, skepticism and rumours of blood stealing researchers. When it came to gathering subjects, researchers were rarely involved in the challenging work of enticing villagers to participate, preferring to rely on chiefs. Chiefs, however, often relied on heavy-handed and ethically questionable techniques. The article concludes by looking at the much-discussed concept of group consent, and showing that historically a chief never had the authority to consent on behalf of villagers.     

Guest Lecture 9.45–10.30 Wednesday 17 September 2003. Csp Colposcopy Guidelines

The success of the Cervical Screening Programme (CSP) is due in part to its management being underpinned by Quality Assurance. These measures ensure uniform standards across the country. Since 1992 Colposcopy Guidelines have been in place; these were updated in 1997 and have just been redefined. It is entirely consistent with the National CSP that colposcopy is governed by Guidelines. The aim of clinical practice guidelines is to raise the standard of care and improve outcomes. The objectives are, therefore:

• a) to develop evidence based guidelines;
• b) to ensure the guidelines are widely adopted.

The credibility of guidelines is crucial to their adoption and this depends far more on the demonstration of an evidence base than that the authors are ‘experts’. Development by a professional group or body who are seen as having a legitimate role is very important as is involvement of all ‘stakeholders’ in ensuring acceptability. In terms of their nature, guidelines should be valid i.e. they will achieve what they are intended to achieve, and they should be robust i.e. they will work when implemented by different individuals in different settings. Colposcopy lends itself well to guidelines because it is largely a routine practice, but substandard care can have serious consequences. In previous years there has been a set of Guidelines for Practice ^1, 1Duncan 1992 ² 2Duncan 1995 and a set of Quality Standards ³ 3Luesley 1996 . On this occasion these two components have been put together in a simple publication. It needs to be borne in mine that the new guidelines were being developed in the context of a number of potential changes which could interact with each other and impact on the Guidelines. These include: The process for the development of the Guidelines included an Editor, an editorial group, and a group of contributors to produce a draft set of evidence based guidelines across 18 areas. New areas covered included HIV +ve women, immuno suppressed women, and working practice. The draft has been available for comment for several months and amendments have been made. Clearly there are areas where evidence is lacking and where different views are expressed. The most contentious area not surprisingly is in the topic of managing mild dyskaryosis; controversy in this has persisted for many years. The quality standards are either attainable or within attainment and are a driver for rising standards. These programme practice guidelines and standards have earned UK colposcopy international respect. They provide a benchmark for QA assessment and will continue to require amendment as new developments come into being.     

Posters. P3 North west non‐gynaecological cytology EQA pilot CD ROM scheme 2002–2003

The 8th circulation of this scheme was preceded by a CD ROM circulation of selected digital images and presented as individual JPEG file images in a single folder on the CD ROM. The number of images per case ranged from three to eight. The delegates will have an opportunity to assess these themselves prior to uncovering the consensus diagnosis provided by the participants. Of the 76, 29 participants of the scheme provided a completed answer sheet for the image‐based circulation. To date, 19 have now also supplied answers on the actual slide circulation. The same diagnosis on image and slide circulation varied from 5/19 to 19/19 with a mode of 14/19. The case that provided the poorest correlation was because of a generalized undercall of suspicious in a case which achieved almost complete consensus on the slide circulation. It had been the most difficult to photograph. The case that provided the next poorest correlation 11/19 was the case that had the poorest consensus diagnosis on the slide circulation. The two cases that provided the best correlation 18/19 and 19/19 were two cases that provided 100% consensus diagnosis on the slide‐based circulation. Comments were received from 20 participants about the image circulation ranging from ‘great’ to ‘awful’ with the majority of 12 participants not happy for their diagnostic capability to be assessed on such images alone. Two stated that the CD was easier to use on their home computer than their NHS one. In conclusion an image circulation overcomes many of the inherent problems with a slide circulation for EQA purposes and can provide an overall 70% correlation with a slide circulation but a significant number of pathologists do not find this an acceptable method for EQA.     

Mesothelioma Symposium 11.30–12.30 Tuesday 16 September 2003. Cytopathology of malignant mesothelioma

The diagnosis of malignant mesothelioma on the cytology of serous effusions is a two‐phase process. First is to determine that the effusion is malignant based on morphological features such as a highly cellular fluid with many large three dimensional cell aggregates, and/or the recognition of minor malignant criteria including prominent cell engulfment, uniformly present very prominent nucleoli, or the finding of very large (giant) cells. In cell block sections, strong positive staining with EMA often with cell membrane accentuation provides compelling support for a cytological diagnosis of malignancy. Second is to recognize that the malignant cells have a mesothelial phenotype and do not represent metastatic malignancy (usually adenocarcinoma). Criteria in support of mesothelioma include the lack of a ‘two cell’ population, that is one native (mesothelial) and one foreign (metastatic), cells with abundant dense staining cytoplasm, the presence of ‘windows’ where mesothelioma cells lie in close apposition and intracytoplasmic glycogen presenting either as small peripheral vacuoles on MGG stained smears or large yellow refractile crescents on Papanicolaou stained smears. In addition, mesothliomas often possess connective tissue stromal cores occurring as either well‐formed collagen within papillary aggregates or lying free as pink (MGG) or light green (Pap) amorphous material in the background of the smear or in loose association with mesothelioma cells. Finally small orange staining squamous‐like cells can occasionally be identified and sometimes this may be a very prominent finding and has resulted in the false impression of a squamous cell carcinoma. Almost certainly these cells represent apoptotic tumour cells. The connective tissue mucin hyaluronic acid may be found as a net‐like pattern in the smear background or as large hard‐edged magenta‐stained vacuoles on MGG‐stained smears. Cell block sections provide architectural information and it is usually possible to separate mesothelioma aggregates with their cuboidal cells, central nuclei and abundant dense cytoplasm arranged in solid, papillary or hollow clusters from those of adenocarcinoma with less dense, often foamy cytoplasm, often composed of columnar cells with elongated nuclei. Aggregate form in adenocarcinoma can be variable but true acini are a rare finding. These cell block sections provide an ideal medium for histochemistry (PAS with and without diastase digestion) and immunocytochemistry. By using a panel of antibodies (Calretinin and CK 5/6, BerEp4, CEA, B72.3) it is almost always possible to distinguish mesothelioma from metastatic adenocarcinoma. Calretinin and CK 5/6 positive staining and absent staining with BerEp4, CEA and B72.3 is considered diagnostic of mesothelioma.