The cytological localization of intracellular neuronal acetylcholinesterase

Sections of cat ciliary ganglia were stained for acetylcholinesterase activity by several modifications of the acetylthiocholine method in order to achieve optimal accuracy of cytological localization of the enzyme. These were compared by ordinary light and phase contrast microscopy with similar sections stained by standard techniques for Nissl substance, the Golgi apparatus, and the neurofibrillae, and by intravital methylene blue. The pattern of cytoplasmic distribution of acetylcholinesterase corresponded most closely with that of the Nissl substance. Following total inactivation of the ganglionic acetylcholinesterase by intravenously administered di-isopropyl fluorophosphate, the reappearance of the enzyme in vivo occurred at the same cytoplasmic sites prior to its reappearance at the cell membrane or preganglionic axonal terminations. These observations, and reports cited from the literature, provide support for the hypothesis that acetylcholinesterase is synthesized within the endoplasmic reticulum, then transported via its canaliculi to the surface of the cell and its processes, where its functional sites are oriented externally to the lipoidal membrane.     

False-negative Papanicolaou smears from women with cancerous and precancerous lesions of the uterine cervix

The occurrence from 1980 to 1989 of false-negative Papanicolaou smears in women with cancerous and precancerous lesions of the uterine cervix was studied. The 4,781 cases of cancer (2,814 invasive carcinomas and 593 carcinomas in situ) and precancerous lesions (418 severe dysplasias, 748 moderate dysplasias and 208 mild dysplasias) included 70 cases (1.5%) with false-negative smears. These 70 cases included 43 invasive carcinomas (61.4%), 17 carcinomas in situ and adenocarcinomas in situ (24.2%), and 10 dysplasias (14.4%); all were diagnosed histologically. The mean age of women with false-negative smears was 44.1 +/- 13.7 years. Review of the original cytologic samples showed a screening error in 41 cases (58.5%), an interpretation error in 2 cases (2.9%) and a sampling error in 27 cases (38.6%). Methods for eliminating false-negative smears are discussed.     

Characteristics of tumour vessels in cytological squash smears of astrocytic tumours

S. Sato, Y. Sato, K. Marutsuka, H. Takeshima and Y. Asada Characteristics of tumour vessels in cytological squash smears of astrocytic tumours Objective: Smear preparations are useful tools from which to diagnose brain tumours intraoperatively. Although vascular proliferation is histologically a key feature of high‐grade astrocytoma, the characteristics of tumour vessels in smear preparations have not been determined. Methods: We examined the density and morphological parameters (area, width, nuclear layer and branches of vessel wall) of tumour vessels in squash smears of 43 primary astrocytomas (grade II diffuse astrocytomas, n = 9; grade III anaplastic astrocytomas, n = 13; grade IV glioblastomas, n = 21) and normal brain tissues (n = 11). Results: Vessel density and all morphological parameters were significantly higher in grade IV than in the other grades of tumours and in normal brain tissue. Vessel area, width and nuclear layer were greater in grade III than in normal brain tissue. The sensitivity and specificity of these vessel parameters for astrocytomas were 75–100% and 82–100%, respectively. Conclusions: Tumour vessel evaluations from squash smears provide useful information for the intraoperative diagnosis and grading of astrocytic tumours.     

Microglandular hyperplasia of the uterine cervix. Cytologic diagnosis in cervical smears

OBJECTIVE: To identify cytomorphologic features specific to microglandular hyperplasia (MGH) in cervical cytologic smears. STUDY DESIGN: Twenty-four cervical smears from 24 patients obtained before the histologic diagnosis of MGH made on colposcopically directed biopsies during a period of two years (1995-1997) were evaluated. RESULTS: Of cases with MGH, 13/24 (54%) showed the presence of bidimensional or tridimensional cellular clusters made up of cubic or cylindrical glandular cells with vacuolated cytoplasm; cells with dense cytoplasm, basaloid in appearance, corresponding to immature squamous metaplasia; and subcylindrical reserve cells with small, round nuclei and scant cytoplasm. Clusters showed microlumina or fenestrated spaces, preserved polarity and absence of nuclear peripheral dispersion. In the control group these cellular clusters were found in 6/100 (6%). Statistical analysis (chi 2) showed a strong, highly significant association (P < 0.001) of the cytologic parameters selected and the histologic diagnosis of MGH. CONCLUSION: Until now, no specific cytologic parameters were described for MGH. This study underscored the value of cytomorphologic parameters described for typical cellular clusters showing microlumina or fenestrated spaces with shared party walls and an admixture of glandular cells, and immature squamous metaplastic and subcylindrical reserve cells in the cytologic diagnosis of MGH.     

Classification of cervical smears with discordance between the cytologic and/or histologic ratings

The problems of diagnostic variability between certified cytotechnologists was studied. Three cytology laboratories submitted a total of 28 cervical smears that had a discordance between the cytologic and/or histologic ratings. Eight independent cytotechnologists provided blind readings on each slide, expressed as "absence of cervical intraepithelial neoplasia (CIN)" to "CIN III." The median rating was absence of CIN or CIN I for 8 slides, CIN II for 5 and CIN III for 15. With a kappa value greater than 0 reflecting agreement beyond chance expectation and a value of 0.40 indicating fair agreement, the kappa value for 8 X 28 ratings was 0.36 (P = .0001), with a 90% confidence interval (CI) between 0.34 and 0.37. The kappa value was 0.14 (P = .10), with a 90% CI between 0.10 and 0.18, on a subsample of nine smears with two or more positive cytology diagnoses but a negative histology. Sixteen of the 28 slides represented cases of histologically proven cancer. Treating cytologic diagnoses of CIN II and CIN III as positive, the sensitivity of the cytologist with reference to histology varied between 71% and 86% while the specificity ranged from 18% to 62%. The positive predictive value was 1/2.5 to 1/1 and the negative predictive value was 1/6 to 1/1. The predictive power (true positives/false positives) ranged from 1.0 to 2.2. The cytodiagnosis of these cervical smears from cases of discordance thus exhibited limited reliability. Standardization of the relevant cytologic knowledge and its routine application is needed to improve the level of performance.     

Review of cervical smears from 76 women with invasive cervical cancer: cytological findings and medicolegal implications

OBJECTIVE: To review cervical smears from 76 women which were taken prior to the diagnosis of invasive cervical cancer and to determine the appropriateness of the cytology reports issued on the smears. METHODS: Cervical smears, clinical records, cervical smear history and cytology reports from 76 women with invasive cervical cancer were reviewed. After microscopic review of the cervical smears, the cases were divided into two groups: Group 1 comprised 50 women who were found to have had at least one false-negative (F/N) smear report prior to the diagnosis of invasive cervical cancer. Group 2 comprised 26 women for whom no evidence of F/N reporting was found. RESULTS: A total of 209 cervical smears from the 50 women in group 1 were available for review (range 2-12 smears per woman); 100 of the 209 smears were considered to have been reported appropriately. Ninety-seven smears which had been reported originally as negative or inadequate were found, on review, to contain numerous severely dyskaryotic cells and were reclassified as F/N smears. All of the 50 women had at least one F/N smear and 29 had two or more. Twelve smears from eight women contained only a few (<200 severely dyskaryotic cells). Forty women developed invasive squamous carcinoma and 10 developed invasive adenocarcinoma. The stage at diagnosis ranged from 1A to stage 4. Seventy-one smears from the 24 women in group 2 were available for review (range 1-15 smears per woman). In two cases included in group 2, no smears were provided for review as the smears had been lost or mislaid. Review of the 71 smears confirmed the accuracy of the original cytological classification of the smear. Nineteen women were diagnosed with squamous cancer, two microinvasive cancer, one glassy cell, two adenocarcinomas, and one with adenosquamous carcinoma. One women was found to have an embryonal rhabdomyosarcoma of the corpus uteri involving the cervix. DISCUSSION/CONCLUSION: The medicolegal implications are discussed in the light of the above findings. Evidence of breach of duty of care was presented in all 50 cases in group I although causation was not established in every case. There was no evidence of failure of duty of care in terms of the standard of the cervical cytology reports issued or standard of clinical management in 17 of the 26 cases in group 2. However, in seven of the 26 cases in group 2, clinical management of the case was substandard due to failure to investigate symptoms of irregular bleeding regardless of a negative cytology report (two cases), failure to act upon a suspicious smear report or consecutive inadequate smear reports (two cases), failure of follow-up after treatment of CIN3 (two cases) and histological misdiagnosis (one case).     

Significance of cytologic smears in the diagnosis of small cell carcinoma of the uterine cervix

OBJECTIVE: To provide improved identification of small cell carcinoma (SMCC) and reevaluate the significance of cervical cytologic smears in its diagnosis. STUDY DESIGN: Analyses of histocytologic morphology and clinical data were performed by reviewing clinical records, histopathology and cervical cytology smears from 18 SMCC cases of the uterine cervix (including one recurrent case and three SMCC cases with adenocarcinoma) between 1986 and 2001. RESULTS: Most cases showed minimal cytoplasm, finely stippled ("salt and pepper") chromatin, prominent nuclear molding and smearing effect. Cytologic smears diagnosed or suggested 79% of SMCC cases before histologic confirmation. Of the cases, 89% displayed moderate to high cellularity. The tumor cells were arranged mostly in clusters of varying sizes with no typical architectural pattern. In addition, the tumors often exhibited very pleomorphic cells and recognizable nucleoli. CONCLUSION: Cytologic features of SMCC cells are characteristics enough for specific diagnosis or at least an early indication of it. Timely detection by cervical cytologic smears will allow clinicians to initiate prompt treatment of these aggressive tumors.     

Efficacy of cotton-tipped applicators for obtaining cells from the uterine cervix for Papanicolaou smears

A study was made of the efficacy of two techniques for the preparation of Papanicolaou smears. In one technique ("swab-spatula technique"), a scraping of the endocervix with a saline-moistened cotton-tipped applicator was combined with a scraping of the ectocervix with a plastic spatula. In the second technique ("swab technique"), the endocervix and ectocervix were scraped with only a saline-moistened cotton-tipped applicator. The swab technique produced more inadequate smears with a scanty cellular yield (24/408 = 6%) than did the swab-spatula technique (9/361 = 3%). The swab technique also produced higher false-negative rates (60% for CIN I, 42% for CIN II, 16% for CIN III, 20% for invasive cancer, and 32% overall) as compared with those of the swab-spatula technique (27% for CIN I, 29% for CIN II, 14% for CIN III, 0% for invasive cancer and 18% overall). Because of the higher rates of inadequate samples and false negativity in smears prepared by cotton-tipped applicators alone, it is recommended that the spatula not be omitted in taking cervical samples for the preparation of Papanicolaou smears for the detection of dysplasia or cancer. This study also reflects a poor performance of a cervical cancer detection system in the setting of a major medical school and suggests the need for instruction and periodic evaluation of the performance of the staff taking the smears. This study also substantiates doubt on the value of a second recent smear as a follow-up procedure for cervical dysplasia.