False Negative Results in Cervical Cancer Screening-Risks, Reasons and Implications for Clinical Practice and Public Health

False negative (FN) results in cervical cancer (CC) screening pose serious risks to women. We present a comprehensive literature review on the risks and reasons of obtaining the FN results of primary CC screening tests and triage methods and discuss their clinical and public health impact and implications. Misinterpretation or true lack of abnormalities on a slide are the reasons of FN results in cytology and p16/Ki-67 dual-staining. For high-risk human papillomavirus (HPV) molecular tests, those include: truly non-HPV-associated tumors, lesions driven by low-risk HPV types, and clearance of HPV genetic material before sampling. Imprecise disease threshold definition lead to FN results in visual inspection with acetic acid. Lesions with a discrete colposcopic appearance are a source of FN in colposcopic procedures. For FAM19A4 and hsa-miR124-2 genes methylation, those may originate from borderline methylation levels. Histological misinterpretation, sampling, and laboratory errors also play a role in all types of CC screening, as well as reproducibility issue, especially in methods based on human-eye evaluation. Primary HPV-based screening combined with high quality-assured immunocytochemical and molecular triage methods seem to be an optimal approach. Colposcopy with histological evaluation remains the gold standard for diagnosis but requires quality protocols and assurance measures.

Relationship Between CA 19.9 and the Lewis Phenotype: Options to Improve Diagnostic Efficiency

BACKGROUND/AIM

Approximately 10% of patients are unable to synthesize CA 19.9 (Lewis-negative), and these results are erroneously considered false-negatives. The aim of this study was to confirm that CA 19.9 cannot be detected by immunoassays in Lewis-negative patients.

MATERIALS AND METHODS

CA 19.9 levels were measured by immunological assays and Lewis phenotype was determined by the haemagglutination reaction.

RESULTS

Patients with Lewis phenotype (a+b-) or (a-b+) had significantly higher CA 19.9 levels than Lewis-negative patients with active cancer (p<0.001), no-evidence of disease (NED) patients (p<0.001) or patients with benign disease (p<0.001). Ninenty-four percent of patients (33/35) with undetectable CA 19.9 had a Lewis-negative phenotype. Additionally, 94.7% (34/36) of patients with Lewis-negative phenotypes had undetectable CA 19.9 serum levels.

CONCLUSION

Patients with undetectable CA 19.9 serum levels tend to be Lewis-negative, and CA 19.9 is not useful in diagnosis or follow-up.

Value of fine-needle aspiration in evaluating large thyroid nodules

BACKGROUND

The American Thyroid Association (ATA) recommends using ultrasound-guided fine-needle aspiration (FNA) in order to evaluate supracentimetric and suspect thyroid nodules. The purpose of this study was to evaluate the effective use of FNA before surgery for nodules over 3 cm in diameter.

METHODS

In this retrospective study, we analyzed the results of ultrasound-guided FNA and postoperative histological analysis in 843 nodules >3 cm.

RESULTS

The FNA was informative in 42.6%. The correlation with the final histological analysis was 94.8% for benign nodules and 71.0% for malignant nodules. The FNA had a positive predictive value of 71%, a specificity of 97%, a sensitivity of 56%, and a 4.7% rate of false-negative results.

CONCLUSION

Because there is a nonnegligible FNA risk of error, notably allowing the evolution of a cancer in 1 of 20 cases, the FNA data should not delay surgical intervention for potentially suspect nodules >3 cm in diameter. © 2016 Wiley Periodicals, Inc. Head Neck 39: 32-36, 2017.

Detection of a divergent Parainfluenza 4 virus in an adult patient with influenza like illness using next-generation sequencing

BACKGROUND

Human Parainfluenza viruses are a common cause of both upper and lower respiratory tract infections, particularly in children. Of the four Parainfluenza virus serotypes, Parainfluenza 4 is least well characterised from both the clinical, epidemiological and genetic perspectives.

METHODS

Flocked nose or throat swabs from a previous study investigating viral prevalence in community-based adults suffering from influenza like illness were used as the basis for this study. Samples in which no virus was detected using a 16 viral respiratory pathogen real-time PCR panel were barcoded and pyrosequenced using the Roche 454 GS FLX Titanium chemistry. The sequences were analysed using the VirusHunter bioinformatic pipeline. Sanger sequencing was used to complete the detected Parainfluenza 4 coding region.

RESULTS

A variant Parainfluenza 4 subtype b strain (QLD-01) was discovered in an otherwise healthy adult who presented with influenza like illness. Strain QLD-01 shared genomic similarities with both a and b subtypes. The extent of divergence of this genome from the 5 available whole Parainfluenza 4 genomes impacted the predicted binding efficiencies of the majority of published Parainfluenza 4 PCR assays.

CONCLUSIONS

These findings further support a possible role for Parainfluenza 4 in the aetiology of adult respiratory disease within the community setting, and highlight the caution needed to be used in designing PCR assays from limited sequence information or in using proprietary commercial PCR assays.

False-negative results of breast core needle biopsies - retrospective analysis of 988 biopsies

BACKGROUND

Breast cancer is the most common malignant neoplasm and the most common cause of death among women. The core needle biopsy is becoming a universal practice in diagnosing breast lesions suspected of malignancy. Unfortunately, breast core needle biopsies also bear the risk of having false-negative results.

MATERIAL/METHODS

988 core needle breast biopsies were performed at the Maria Skłodowska-Curie Memorial Cancer Center and Institute of Oncology, Gliwice Branch, between 01 March 2006 and 29 February 2008. Malignant lesions were diagnosed in 426/988 (43.12%) cases, atypical hyperplasia in 69/988 (6.98%), and benign lesions in 493/988 (49.90%) cases.

RESULTS

Twenty-two out of 988 biopsies (2.23%) were found to be false negative. Histopathological assessment of tissue specimens was repeated in these cases. In 14/22 (64%) cases, the previous diagnosis of a benign lesion was changed. In 8/22 (36%) cases, the diagnosis of a benign lesion was confirmed. False-negative rate was calculated at 2.2%. The rate of false-negative diagnoses resulting from a radiological mistake was estimated at 36%. The rate of false-negative diagnoses, resulting from histopathological assessment, was 64%. False-negative results caused by a radiological error comprised 1.5% of all histopathologically diagnosed cancers and atypias (sensitivity of 98.5%). There were no false-positive results in our material - the specificity of the method was 100%.

CONCLUSIONS

Histopathological interpretation is a substantial cause of false-negative results of breast core needle biopsy. Thus, in case of a radiological-histopathological divergence, histopathological analysis of biopsy specimens should be repeated. The main radiological causes of false-negative results of breast core needle biopsy are as follows: sampling from an inappropriate site and histopathological non-homogeneity of cancer infiltration.

False negative results in glaucoma detection with Heidelberg Retina Tomograph II

Purpose

To evaluate the rate of false negative results with the Heidelberg Retina Tomograph (HRT II) in a glaucoma practice.

Design

Cross-sectional study.

Methods

We analyzed the HRTs taken between October 2002 and October 2003 in our glaucoma clinic, and selected the patients who had a good quality image (SD < 40 μ) with a normal Moorfield’s Regression Analysis (MRA). A masked independent observer classified those patients as normal, glaucoma suspect, or glaucomatous on the basis of optic disc stereo photos (ODP) and at least 2 consecutive reliable automated perimetries. The diagnosis of glaucoma was based on a glaucomatous optic disc with a congruent, reproducible visual field defect.

Results

Four hundred and fifty patients who had undergone an HRT examination were analyzed. One hundred and nine patients had an HRT classified as normal on the MRA, and a good quality image. Fifteen of those 109 patients (13.7%) were classified as glaucomatous on the basis of an abnormal ODP with corresponding visual field defect. Seven (6.4%) patients were classified as glaucoma suspect.

Conclusion

Fourteen percent of glaucoma patients with glaucoma remained undetected with the HRT II Moorfield’s regression analysis as a sole means to detect glaucoma.