Prospective parallel randomized trial of the MultiCyte™ ThinPrep(®) imaging system: the Scottish experience.

BACKGROUND: Computer-assisted screening of cervical liquid-based cytology (LBC) preparations using the ThinPrep® Imaging System (TIS) has shown improved qualitative and quantitative gains. The use of Multicyte™ has not been described in a well-established national screening programme with a low incidence of high-grade dyskaryosis. OBJECTIVES: To assess the impact of computer-assisted screening within the Scottish Cervical Screening Programme (SCSP). METHODS: Two groups of three laboratories, each sharing a ThinPrep® Imager, screened 79 366 slides randomized to test and 90 551 to control arms by laboratory accession. Screeners were not blinded. Standard laboratory reporting profiles of the SCSP, sensitivity, specificity and false-negative rates of all grades of LBC abnormalities with respect to final cytology reports, predictive value for cervical intraepithelial neoplasia grade 2 or worse (CIN2+) on histology; and screening rates were compared for both arms. RESULTS: Inadequate and negative reporting rates were significantly lower and low-grade reporting rates significantly higher in the imager arm. Imager-assisted screening showed significantly better specificity than manual screening with respect to the final cytology result. There was no evidence of a significant difference in the detection of CIN2+ or CIN3 +. Positive, abnormal and total predictive values (high-grade, low-grade and all abnormal cytology found to be CIN2+, respectively) were similar in both arms. Productivity was significantly higher in the imager arm. CONCLUSION: Computer-assisted screening in a well established screening programme showed significantly improved productivity without loss of quality. These findings should inform future policy for cervical screening programmes.

Endobronchial ultrasound-transbronchial needle aspiration and its practical application.

Endobronchial ultrasound-transbronchial needle aspiration (EBUS-TBNA) has emerged over the past decade as one of the most exciting and innovative developments in the field of respiratory medicine. This procedure allows sampling of mediastinal lymph nodes and masses in both malignant and benign disease and overcomes some of the disadvantages associated with mediastinoscopy and blind transbronchial needle aspiration. We describe the clinical use, indications for and limitations of EBUS-TBNA along with several illustrated clinical examples.

An investigation of adequate volume for the diagnosis of malignancy in pleural fluids.

OBJECTIVE: The cytological examination of pleural effusions is an important investigation in the diagnosis of malignancy. Maximizing the chances of identifying malignant effusions is therefore desirable. Recent Royal College of Pathologists guidelines, based on the British Society for Clinical Cytology codes of practice, have suggested that a minimum of 20 ml of pleural fluid is required for diagnostic purposes. METHODS & RESULTS: We examined 2155 pleural fluids received over a 6-year period in order to define a minimum required volume for adequacy. By examining the plateau phase of a graph of threshold volumes for initial samples received for each patient (n =1584) we determine that a minimum fluid volume of 25 ml is required and that more than 50 ml does not improve sensitivity. CONCLUSION: Between 25 and 50 ml of fluid are required for the adequate assessment of pleural effusions for malignancy.

Interdigitating dendritic cell sarcoma of the parotid gland.

Interdigitating dendritic cell sarcomas (IDCSs) are extremely uncommon tumours that arise predominantly in lymphoid tissue. We report a case of an IDCS arising in the parotid gland of a 73-year-old man. Clinically, a primary salivary gland tumour was suspected but fine needle aspiration cytology suggested a soft tissue tumour. A diagnosis of IDCS was made on histopathological examination of the resection specimen, with subsequent confirmation by electron microscopy. Given the extreme rarity of this tumour at this site, it is unlikely to be a common diagnostic problem, but the importance of multiple diagnostic modalities is emphasized. The findings of cytology, histology, immunohistochemistry and electron microscopy have not previously been described together in a single case report of this tumour.

Preoperative histological classification of primary lung cancer: accuracy of diagnosis and use of the non-small cell category.

AIMS: To compare the preoperative classification of lung carcinoma made on cytological and histological specimens with the postoperative classification made on the resected specimen. In addition, to find out how often the term "non-small cell lung cancer, not otherwise specified" (NSCLC) was used, and in such cases to note the final diagnosis. METHODS: Between 1991 and 1995, 303 patients had a lung resection in Aberdeen for primary carcinoma. For each patient, the departmental records were examined for preoperative specimens (cytological and histological). A note was made of whether each specimen was positive or negative for malignancy and, if positive, what the cell type was. Where patients had more than one sample submitted, the most specific result was taken. RESULTS: Fifty four per cent of patients had a correct specific preoperative diagnosis of malignancy, whereas 34% were labelled as NSCLC. Patients with squamous carcinoma were more likely to have a diagnosis of malignancy (88%) that was specifically correct (75%). Patients who had adenocarcinoma were less likely to have a preoperative diagnosis of malignancy (64%) that was specifically correct (35%). For those in whom a diagnosis of NSCLC was made, 55% turned out to have adenocarcinoma whereas 24% had squamous carcinoma. CONCLUSIONS: By adhering strictly to criteria, a high accuracy of diagnosis can be achieved for squamous carcinoma, but the diagnosis of adenocarcinoma seems to be more of a challenge. NSCLC is a useful and appropriate classification, the use of which reduces the rate of inaccurate specific diagnosis. There are occasions when pathologists can provide a more accurate diagnosis by being less precise.

The accuracy of "one-stop" diagnosis for 1,110 patients presenting to a symptomatic breast clinic.

UNLABELLED: To minimise delay in diagnosis and reduce patient anxiety, triple assessment with immediate reporting has been used in our symptomatic breast clinic since 1991. This article examines the accuracy of the diagnostic modalities used and the efficacy of the "one-stop" diagnostic policy. The data on 1,110 new patients presenting to the symptomatic breast clinic between January and July 1993, were analysed and subsequent three year follow-up and outcome established. Fine needle aspiration cytology (FNAC) gave the highest predictive value (97.3%) with a sensitivity of 93.5% and a specificity of 98.1%. Ultrasonography provided a 97.0% prediction with a sensitivity of 88.9% and a specificity of 97.4%, whereas mammography had a prediction of 96.4% with sensitivity of 93.2% and a specificity of 96.7%. When the mammogram or ultrasound scan were reported as unequivocally benign (M1), there were no missed cancers. The false positive and false negative rates for FNAC were 0% and 1.4%, respectively. Following assessment, a diagnosis was made in 96% of patients. Sixty-two percent of the patients were discharged at the first clinic visit. Four breast malignancies were subsequently diagnosed in the discharged group; two with new microcalcifications due to ductal carcinoma in situ, one with invasive disease in a different quadrant of the breast from that originally investigated, and in one patient the cancer was missed. CONCLUSION: A "one-stop" symptomatic breast clinic provides an accurate and effective means of establishing a correct diagnosis.

A case-control study of true-positive versus false-negative cervical smears in women with cervical intraepithelial neoplasia (CIN) III.

Cervical smears (n = 150) from five departments showing high-grade dyskaryosis were examined by three cytologists. All the smears came from patients with biopsy-proven CIN III. One hundred had been correctly reported (true positives) but 50 had originally been reported as negative and had been found to be positive only on review (false negatives). There were significant differences between the two sets in the characteristics of the dyskaryotic cell population. The false-negative smears tended to have fewer than 200 dyskaryotic cells. The nuclei of the dyskaryotic cells tended to have fine rather than coarse nuclear chromatin. A smear with fewer than 50 dyskaryotic cells is 26 times more likely to be reported as negative than one with more than 200 dyskaryotic cells. The results suggest that there is a type of severely dyskaryotic smear that is inherently likely to be missed on routine screening.

A novel diagnostic index for use in the breast clinic.

The diagnostic accuracy of clinical examination, mammography, ultrasonography and fine needle aspiration (FNA) cytology in discriminating between benign and malignant breast lesions has been retrospectively assessed in 603 patients who attended the Professorial Breast Clinic and then underwent surgical biopsy, in Aberdeen Royal Infirmary, between January 1989 and September 1992. In this series of patients, FNA cytology gave the highest overall prediction of malignancy (92.6%) with a sensitivity of 87% and a specificity of 98%, whilst ultrasonography gave the lowest correct overall prediction (75.6%), with a sensitivity of 70% and a specificity of 79%. Using all the available findings (clinical examination, mammography, ultrasonography, FNA) as well as the patients' age, a stepwise logistic discriminant analysis was used to derive a mathematical equation for use as a novel diagnostic index. Weighted scores, derived from each variable, were used in the discriminant equation to predict the likelihood of malignancy in patients of different ages (>90%). For young patients (<35 years) the discriminant analysis predicted the diagnosis in 98% of women correctly. Quadruple assessment provides an opportunity for establishing the likely diagnosis in most patients the same day they visit the Breast Clinic. The diagnostic index, currently being evaluated prospectively in our breast clinic, may be a further aid to establishing a correct diagnosis.

An audit of the clinical investigation of pleural effusion.

BACKGROUND: Pleural aspiration with pleural biopsy is advised for the investigation of pleural effusion. The clinical investigation of pleural effusion in a group of teaching hospitals was audited with reference to adequacy and diagnostic value of sampling procedures. METHODS: A retrospective review of case records of all patients investigated for pleural effusion during an eight month period was performed. The records of 112 patients, age range 16-91 years, who underwent 150 procedures were reviewed. RESULTS: Microbiology samples were obtained from 137 procedures, of which five provided a positive culture, including one for mycobacteria. Cytology samples were obtained from 145 procedures though approximately two thirds of samples were less than the recommended 30 ml. The pleural biopsy rate was 30%, varying from 0% in general or thoracic surgery to 68% in thoracic medicine (thoracic surgeons carried out thoracoscopy). Twenty nine per cent of pleural biopsy samples were of poor quality. The complication rate was 2% for aspiration alone, and 4% for aspiration plus biopsy. The sensitivity of the first diagnostic procedure for a diagnosis of malignancy or tuberculosis was 53% for cytology alone, 50% for biopsy alone and 72% for cytology plus biopsy. CONCLUSION: The samples obtained from pleural aspiration and biopsy in the initial investigation of pleural effusion are often inadequate. Further education is necessary to improve the quantity and quality of specimens submitted for histological and cytological examination.

The distribution of lymph nodes in and around the parotid gland: an anatomical study.

The numbers of lymph nodes in and around the parotid salivary gland and their sites in relation to the facial nerve within that gland have been established in the 20 glands of 10 individuals whose age distribution approximated to that of patients most likely to suffer metastatic disease to these nodes. Virtually all the nodes were found to be superficial to the facial nerve.

Metastatic patterns of squamous carcinoma in the parotid lymph nodes.

The clinical and pathological patterns of squamous carcinoma of the skin metastasising to the parotid lymph nodes have been analysed in 28 patients in whom such metastasis occurred over the period 1972 to 1981. Prognosis appears to be closely related to whether tumour has spread out with the nodes into the parenchyma of the parotid gland or is still confined within the nodes.