SPUTUM CYTOLOGY

Respiratory Cytology--Current Trends Including Endobronchial Ultrasound-Guided Biopsy and Electromagnetic Navigational Bronchoscopy: Analysis of Data From a 2013 Supplemental Survey of Participants in the College of American Pathologists Interlaboratory Comparison Program in Nongynecologic Cytology

CONTEXT

Nongynecologic cytology (NGC) practices are expanding in relationship to historical gynecologic cytology screening programs. Bronchopulmonary cytology is experiencing an evolution regarding new procedural types. The College of American Pathologists (CAP) tracks practice patterns in NGC by developing questionnaires, surveying participants, and analyzing respondent data.

OBJECTIVE

To analyze responses to a 2013 CAP supplemental survey from the Interlaboratoy Comparison Program on bronchopulmonary NGC.

DESIGN

The "NGC 2013 Supplemental Questionnaire: Demographics in Performance and Reporting of Respiratory Cytology" was mailed to 2074 laboratories.

RESULTS

The survey response rate was 42% (880 of 2074) with 90% of respondents (788 of 880) indicating that their laboratories evaluated cytology bronchopulmonary specimens. More than 95% of respondents indicated interpreting bronchial washings (765 of 787) and bronchial brushings (757 of 787). A minority of laboratories (43%, 340 of 787) dealt with endobronchial ultrasound-guided samples, and an even smaller fraction of laboratories (14%, 110 of 787) saw cases from electromagnetic navigational bronchoscopy. Intraprocedural adequacy assessments by pathologists (and less often by cytotechnologists or pathologists-in-training) were routinely performed in percutaneous transthoracic aspiration cases (74%, 413 of 560) with less involvement for other case types. Most laboratories reported that newly diagnosed primary pulmonary adenocarcinomas were triaged for molecular testing of epidermal growth factor receptor and anaplastic lymphoma kinase.

CONCLUSIONS

The parameters examined in this 2013 survey provide a snapshot of current pulmonary cytopathology practice and may be used as benchmarks in the future.

Can free DNA be detected in sputum of lung cancer patients?

SUMMARY

Free DNA is present in the serum of cancer patients in a higher concentration than that in non-cancer patients. Free DNA in sputum may originate from malignant or inflammatory diseases. The aim of the study was to examine the presence of free DNA in sputum and the relationship to lung cancer. The contribution of inflammatory cells was established as well. The amount of free and cellular DNA in sputum was determined using real-time beta-globin PCR in 28 lung cancer patients and 68 controls. Free DNA was present in sputum samples of the cancer patients and controls. We found no differences in DNA concentration in sputum of patients with and without lung cancer. For all patients combined the amount of free DNA was related to the amount of inflammation. Further, we found increased hypermethylation of RASSF1A in lung cancer patients compared to controls to show that tumour related DNA is present in sputum. In conclusion, free DNA can be detected in sputum of lung cancer patients. The amount of free DNA is related to the amount of inflammation, but not to the presence of lung cancer.

[Usefulness of induced sputum cytology in the study of central masses in elderly patients]

OBJECTIVE

To analyze the diagnostic yield of cytology obtained by means of sputum induction in elderly patients with central masses.

METHODS

A total of 23 patients older than 75 years with centrally located pulmonary masses identified by computerized tomography were studied. All patients collected three spontaneously produced sputum specimens and underwent three sputum-induction sessions. Induction was considered satisfactory when the patient expectorated within the following 15 minutes. All sputum specimens were processed by May-Grünwald-Giemsa and Papanicolau staining techniques. The definite diagnostic was considered that obtained by means of bronchial biopsy or chest percutaneous aspirative puncture (PAP).

RESULTS

With sputum induction, 19 patients (83%) collected satisfactory specimens and in 14 cases cytology was positive for malignancy (sensitivity 74%) and negative in five. No false-positive cases were recorded and in no patient did complications occur in association with sputum induction. The analysis of agreement between induced sputum and definite diagnosis showed a kappa index of 0.66.

CONCLUSIONS

Among elderly patients with central pulmonary masses, the cytology of induced sputum should be considered as the first diagnostic procedure because of its harmlessness, remarkable sensitivity and high histologic correlation.