Reassessment of the rate of fixative diffusion

The diffusion of fixatives is slow. Early work using plasma gels and animal tissues showed the distance penetrated by a fixative to be a simple function of the fixation time but this relation has not been established in human tissues. The rates of diffusion into whole human spleens were measured for three primary fixatives over periods ranging from one to 25 days. A positive correlation was demonstrated between penetration distance (mm) and fixation time (hours). The diffusion rates were slower than those in previous studies. These results have possible implications for the handling of surgical specimens.

Anal intraepithelial neoplasia: part of a multifocal disease process

Invasive carcinomas of the anogenital epithelium share a common aetiological factor--human papillomavirus (HPV) type 16. Although genital intraepithelial neoplasia may be multifocal, there have been no studies of the prevalence of anal intraepithelial neoplasia in women with intraepithelial neoplasia of the genital tract. We tested the hypothesis that women with high-grade cervical intraepithelial neoplasia are at higher risk of disease in the anus than are control women of similar age with no history of anogenital neoplasia. 29 (19%) of 152 women with cervical intraepithelial neoplasia grade III had histological evidence of anal intraepithelial neoplasia. Of the 29 patients, 11 had grade III anal lesions; 2 of those women had concomitant invasive anal squamous-cell carcinomas. Only 7% (8/115) women with high-grade lesions of the cervix alone had evidence of anal intraepithelial neoplasia; by contrast, 57% (21/37) of those with more than one focus of intraepithelial neoplasia (cervix plus vulva, vagina, or both) had anal lesions. HPV 16 DNA was identified in 18 (51%) of 35 anal biopsy samples in the study group. No evidence of anal intraepithelial neoplasia was found in the control group (50 women), although 2 patients had grade I cervical lesions. HPV 16 DNA was identified in 12 (24%) of biopsy samples from the cervix and 7 (14%) from the anus in the control group; all 7 women with anal HPV 16 had concomitant cervical infection. The role of anal examination in the assessment of women with any focus of genital intraepithelial neoplasia requires further investigation.

Delay in fixation does not affect the immunoreactivity of proliferating cell nuclear antigen (PCNA)

The effect of delayed fixation on the immunoreactivity of proliferating cell nuclear antigen (PCNA) was investigated using eight breast carcinomas. Topologically shuffled samples of each tumour were immersed in fixative at times of 0.5, 1, 2, 4, 6, 18, and 24 h after surgical removal. In addition to a PCNA index (percentage of positive cells per 1200 tumour cells), a semi-quantitative PCNA grading system was used, based on estimates of more than or less than 50 per cent of positive tumour cells at each time interval. The PCNA index of six tumours increased by a mean of 10 per cent with a fixation delay of 24 h. The PCNA grade of all eight tumours showed no change with delayed fixation.

Nd:YAG laser endometrial ablation: histological aspects of uterine healing

Laser ablation of the endometrium performed under hysteroscopic control is a novel procedure for the conservative management of menorrhagia in cases of dysfunctional uterine bleeding. The effect this has on the uterine cavity and the mechanism of reepithelialisation and endometrial regeneration have been examined by means of histological examination of endometrial biopsies and four hysterectomy specimens obtained for various indications at varying time intervals after laser endometrial ablation. During the first 3 months, fragments of necrotic and granulation tissue are found surrounded by a limited polymorph response. By 3 months, the uterine cavity appears to be completely reepithelialised. After 6 months, areas of normal-appearing endometrium may persist, but in other areas there is an attenuated cuboidal surface epithelium closely applied, to the underlying myometrium. Stromal fibrosis reminiscent of Asherman syndrome is also apparent.

Assessment of specimen fixation in a surgical pathology service

The quality of specimen fixation was examined within a routine diagnostic histopathology service. For each specimen the adequacy of fixation was assessed and the transit time between operating theatre and the laboratory was measured. Preliminary fixation was found to be inadequate in 25% of specimens and some form of manipulation to assist fixation was required in 36% of specimens. The mean transit time was 22 (SD 10.7) hours. Specimen fixation and transport are additional factors to consider in quality assurance of histopathology.

Is the grading of breast carcinomas affected by a delay in fixation?

The effect of delay in fixation on the modified Bloom and Richardson grade of eight breast carcinomas was investigated. Topologically shuffled samples of each tumour were immersed in fixative at times of 0.5, 2, 4, 6, 18 and 24 h after surgical removal. The grade of each tumour was assessed at delays of 0.5 and 6 h. The tubule formation and nuclear pleomorphism components of the grade showed no change with a delay in fixation of 6 h. The number of mitotic figures declined by a mean of 53% over the same period and this resulted in a decrease in the histological grade of one of the tumours. The implications of these findings for the handling of breast specimens in a diagnostic histopathological laboratory are discussed.

Altered patterns of gap junction distribution in ischemic heart disease. An immunohistochemical study of human myocardium using laser scanning confocal microscopy

Arrhythmias are a common and potentially life-threatening complication of myocardial ischemia and infarction in humans. The structural pathways for the rapid intercellular conduction of the electrical impulse that stimulates coordinated contraction in the myocardium are formed by the gap junctions situated at intercalated disks. By raising antibodies to cardiac gap-junctional protein, and using these antibodies in an immunohistochemical procedure in combination with the technique of laser scanning confocal microscopy, we have succeeded in localizing gap junctions, with a clarity not previously possible, through thick volumes of human myocardial tissue. To explore the structural basis for ischemia and infarction-related arrhythmogenesis, antibody labeling and laser scanning confocal microscopy were applied to study the organization, distribution, and other characteristics of gap junctions in the explanted hearts of patients undergoing cardiac transplantation for advanced ischemic heart disease. In areas of myocardium free from histologically detectable structural damage, there was no significant difference in the size of distribution of labeled gap junctions, or in their number per intercalated disk, between left ventricular tissue (in which functional impairment was severe) and right ventricular tissue (in which functional impairment was minimal). However, in myocytes at the border of healed infarcts--zones to which the slow conduction responsible for reentry arrhythmias has been localized--the organization of gap junctions was markedly disordered; instead of being aggregated into discrete intercalated disks, gap-junctional immunostaining was spread extensively over myocyte surfaces. Some infarct zones were bridged by continuous strands of myocytes, coupled to one another by gap junctions, thereby linking healthy myocardium on either side. At their thinnest, these bridges were in some instances no wider than a single attenuated myocyte. The conclusions are 1) a widespread, generalized derangement of gap junction organization does not appear to underlie functional impairment in the ischemic heart, 2) a disorderly arrangement typifies gap junctions in myocytes of the infarct border zone, and this may contribute to alterations in conduction that are capable of precipitating reentry arrhythmias, and 3) delicate chains of myocytes traverse some healed infarcts, apparently forming electrically coupled bridges across what would otherwise constitute blocked zones. The weakest link in this chain can be a single, degenerating myocyte; avoidance of arrhythmia may therefore depend on the continued survival of this single cell.

The decedent affairs office. A unique centralized service

The success of a centralized decedent affairs office depends on support by clinicians, the department chairman, and hospital administration. The benefits to the institution include improved public relations with a decedent's family, compliance with state and federal laws, increased organ donations, and better risk management programs. The only drawback of establishing such an office is the additional personnel necessary for 24-hour coverage. However, modifications in the functions and staffing levels of a decedent affairs office may be made, depending on the needs of individual institutions. We hypothesized that consent for autopsy would be easier to obtain and cause less emotional upheaval for family members if procedures were well established and specially trained individuals were involved in the process. With these ideas in mind, we established a decedent affairs office at The University of Texas Medical Branch in 1984.

In vitro studies of uterine electrosurgery

This study investigated electrosurgical techniques in vitro with emphasis on the tissue effects and heat transfer through full-thickness blocks of excised uterine tissue. Uterine morphometry was also examined. The 7-mm cutting resection loop was associated with a surrounding zone of thermal necrosis between 1.07-1.40 mm. There was no variation in this zone when power was altered, but a statistically significant increase was demonstrated with duration of exposure. A depth of destruction of 3.24-3.49 mm was possible with the desiccating coagulation technique, but fulguration achieved a depth of only 1.70-1.78 mm. A greater tissue effect was demonstrated as time intervals were increased. There was a fall-off in the measured rise in temperature with distance; at 4 mm from the active electrode, a mean rise of 4.5C was noted, whereas at 12 mm the mean temperature rise was 3.9C. There was a statistically significant increase in the mean temperature as power output in the cutting mode was increased. At 180 W, the mean rise was 2.0C but by 260 W, it was 3.9C. When the time interval was increased and the power held constant (220 W), a mean rise of 2.5C was recorded at 1 second, compared with 4.6C at 5 seconds, achieving statistical significance. Power increments in the coagulating mode did not alter the temperature profile, but increasing duration of exposure was associated with a significant rise in mean temperature (from 0.8 to 4.6C). A stepwise increase in the baseline temperature was noted with repetitive insults. The mean myometrial thickness of the anterior and posterior walls measured 1.8 and 1.9 cm, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Liposarcoma of the esophagus

Liposarcoma is one of the most common soft tissue sarcomas found in adults, yet it rarely develops in the alimentary tract. This report describes the pathological features and management of a liposarcoma of the esophagus.

Long survival after excision of a primary malignant melanoma of the oesophagus

A woman who had a large primary malignant melanoma of the oesophagus, with evidence of submucosal invasion and several local metastases, underwent resection two years after the onset of retrosternal pain and has survived for 12 years with no recurrence.

Early amniocentesis at 11-14 weeks' gestation for the diagnosis of fetal chromosomal abnormality--a clinical evaluation

Early amniocentesis between 11 and 14 weeks' gestation was offered to 110 women at risk of a chromosomally abnormal fetus due to maternal age. Four were found to be unsuitable for the procedure, and 106 early amniocenteses were performed. In 102 cases, clear amniotic fluid was obtained with a single tap. There were two dry taps and two bloodstained taps; sampling was repeated in three of these cases before 15 weeks. In the fourth case, placental biopsy was performed at 16 weeks. Thus, we were able to obtain a satisfactory sample in all but three cases (2.8 per cent). Karyotyping of cells harvested from the early amniotic fluid samples was successful in all the 105 cases. Cell culture from the initial samples revealed a normal karyotype in 99 cases, two balanced translocations, two tetraploid karyotypes, and two cases of pseudomosaicism. Of the 105 pregnancies successfully sampled, there have been two losses to date (1.8 per cent). Two further patients presented with premature rupture of membranes, both pregnancies having successful outcomes. Sixty-two babies have delivered to date, with four congenital anomalies. There were no respiratory problems. Twenty-nine pregnancies are continuing without known complications, and details are not yet available on the remaining 12. The results indicate that early amniocentesis may replace the traditional test at 15-17 weeks.

Marking resection margins in surgical biopsy specimens

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The incidence of WESa in 3,072 donors in the United States

The rare red cell antigen, WES(a), which is controlled by an autosomal dominant gene, was reported by Sistonen et al.(1) to have an incidence in the Finnish population of 0.56 percent. A study was undertaken to determine the incidence of the WES(a) antigen within the United States. A total of 3,072 donor samples were obtained for testing from eight different geographical locations. It was determined that the incidence of the WES(a) antigen in the white donor population tested was 2 per 1,610 or 0.12 percent and in the black donor population tested, 7 per 1,460 or 0.48 percent. In the random population the incidence would he 0.29 percent.

Cytogenetic studies of amniotic fluid taken before the 15th week of pregnancy for earlier prenatal diagnosis: a report of 114 consecutive cases

One hundred and fourteen samples of amniotic fluid taken before 15 weeks of gestation were cultured for cytogenetic studies. The results of culturing these early amniotic fluid (EAF) samples were compared with the results of culturing 114 standard amniotic fluid (SAF) samples taken after 15 weeks of gestation matched for maternal age and received in the laboratory within the same week. Cell culture was successful in all 114 of the EAF samples and in 111 SAF samples. There was no significant difference in the days to harvesting and days to reporting in the two groups. Three samples of SAF failed to grow and two EAF samples produced tetraploid karyotypes, so that in these five cases amniocentesis had to be repeated. These problems were attributed to toxicity of a fungicide used in the culture medium. Pseudo-mosaicism was noted in two EAF samples and one SAF sample; and maternal cell contamination was noted in one EAF and one SAF sample. Thus, culturing and karyotyping cells harvested from EAF and SAF are similar, indicating that EAF samples from 12-14-week pregnancies could be used for prenatal diagnosis.

Does delay in fixation affect the number of mitotic figures in processed tissue?

The effect of delay in fixation on the number of mitotic figures in tissues has received little attention, and previous studies have reached differing conclusions. The numbers of mitotic figures in the normal mucosa of six colectomy specimens were counted with delays in fixation of 30 minutes, one hour, two hours, three hours and six hours for samples from each specimen. The numbers of mitotic figures were counted in 50 whole crypts in each specimen by two observers. All phases of mitosis were counted. The number of observable mitotic figures declined by about 30% with a delay in fixation of two hours and by 50% with a delay of six hours. This observation has important implications for the handling of surgical specimens.