Validation of ROS1 by immunohistochemistry against fluorescent in situ hybridisation on cytology and small biopsy samples in a large teaching hospital.

OBJECTIVE: Rearranged ROS1, present in 1%-2% of non-small cell lung cancer (NSCLC) patients, usually young, never or light smokers, is assessed by fluorescence in situ hybridization (FISH) to determine eligibility for tyrosine kinase inhibitors (TKI). Immunohistochemistry (IHC) for the protein product of ROS1 rearrangement, a cost-effective alternative, is validated on cytology and small biopsy samples. METHODS: From 1 March to 31 December 2019, cytology cell blocks and small biopsy samples from a selected cohort of NSCLC patients were concurrently tested for ROS1 gene rearrangement by Vysis 6q22 Break Apart FISH probe and IHC using Cell Signalling D4D6 antibody. Mismatch cases were tested by an RNA fusion next generation sequencing (NGS) panel. RESULTS: In a prospective population of 95 cases, 91 were negative and two were positive by both FISH and IHC. Both dual positive cases were female never smokers and benefited from TKI treatment. Another two cases were positive by FISH but negative by IHC and repeat by NGS showed one to be negative but one failed. Turnaround time for IHC was 0 to 8 days from request to authorisation, whilst that of FISH was 9 to 42 days at a cost of £51 and £159 respectively. CONCLUSION: IHC to assess for the protein product of ROS1 gene rearrangement on cytology cell blocks and small biopsy samples in a routine setting is a promising screening method to assess eligibility for TKI treatment with positive and indeterminate cases confirmed by FISH or NGS as it has good negative predictive value, faster turnaround time and is cost effective, with proven technical and clinical validation.

16/18 genotyping in triage of persistent human papillomavirus infections with negative cytology in the English cervical screening pilot.

BACKGROUND: In the English pilot of primary cervical screening with high-risk human papillomavirus (HR-HPV), we exploited natural viral clearance over 24 months to minimise unnecessary referral of HR-HPV+ women with negative cytology. Three laboratories were permitted to use 16/18 genotyping to select women for referral at 12-month recall. We estimated the clinical impact of this early genotyping referral. METHODS: The observed numbers of women referred to colposcopy and with detected high-grade cervical intraepithelial neoplasia (CIN2+), and of women who did not attend early recall in the three laboratories were compared with those estimated to represent a situation without an early genotyping referral. The 95% confidence intervals (CI) for the differences between the protocols were calculated by using a parametric bootstrap. RESULTS: Amongst 127,238 screened women, 16,097 (13%) had HR-HPV infections. The genotyping protocol required 5.9% (95% CI: 4.4-7.7) additional colposcopies and led to a detection of 1.2% additional CIN2+ (95% CI: 0.6-2.0), while 2.3% (95% CI: 2.1-2.5) fewer HR-HPV+/cytology- women did not attend the early recall compared with the non-genotyping protocol. CONCLUSIONS: In a screening programme with high quality of triage cytology and high adherence to early recall,16/18 genotyping of persistent HPV infections does not substantially increase CIN2+ detection.

Primary cervical screening with high risk human papillomavirus testing: observational study.

OBJECTIVE: To provide the first report on the main outcomes from the prevalence and incidence rounds of a large pilot of routine primary high risk human papillomavirus (hrHPV) testing in England, compared with contemporaneous primary liquid based cytology screening. DESIGN: Observational study. SETTING: The English Cervical Screening Programme. PARTICIPANTS: 578 547 women undergoing cervical screening in primary care between May 2013 and December 2014, with follow-up until May 2017; 183 970 (32%) were screened with hrHPV testing. INTERVENTIONS: Routine cervical screening with hrHPV testing with liquid based cytology triage and two early recalls for women who were hrHPV positive and cytology negative, following the national screening age and interval recommendations. MAIN OUTCOME MEASURES: Frequency of referral for a colposcopy; adherence to early recall; and relative detection of cervical intraepithelial neoplasia grade 2 or worse from hrHPV testing compared with liquid based cytology in two consecutive screening rounds. RESULTS: Baseline hrHPV testing and early recall required approximately 80% more colposcopies, (adjusted odds ratio 1.77, 95% confidence interval 1.73 to 1.82), but detected substantially more cervical intraepithelial neoplasia than liquid based cytology (1.49 for cervical intraepithelial neoplasia grade 2 or worse, 1.43 to 1.55; 1.44 for cervical intraepithelial neoplasia grade 3 or worse, 1.36 to 1.51) and for cervical cancer (1.27, 0.99 to 1.63). Attendance at early recall and colposcopy referral were 80% and 95%, respectively. At the incidence screen, the 33 506 women screened with hrHPV testing had substantially less cervical intraepithelial neoplasia grade 3 or worse than the 77 017 women screened with liquid based cytology (0.14, 0.09 to 0.23). CONCLUSIONS: In England, routine primary hrHPV screening increased the detection of cervical intraepithelial neoplasia grade 3 or worse and cervical cancer by approximately 40% and 30%, respectively, compared with liquid based cytology. The very low incidence of cervical intraepithelial neoplasia grade 3 or worse after three years supports extending the screening interval.

Adenosquamous carcinoma of the lung diagnosed by cytology?: a diagnostic dilemma.

Adenosquamous cell carcinomas of the lung are rare tumours and are associated with a poor prognosis compared to other non-small cell carcinomas. We report a case of a solitary lung carcinoma evaluated by bronchial brush and lavage cytology, bronchial biopsy and pleural fluid cytology. Cytological assessment of the pleural fluid demonstrated non-small cell carcinoma and immunohistochemical staining confirmed a metastatic lung adenocarcinoma. The bronchial brush and lavage specimens, however, demonstrated the cytomorphological features of squamous cell carcinoma, which was confirmed by the bronchial biopsy. The finding of a mixed squamous and glandular component predicts a poor prognosis for this patient. The identification of a squamous component with the non-small cell carcinoma is important as this excludes the patient from anti-VEGF monoclonal antibody treatment due to the increased risk of haemorrhage.