Is Crush Cytology of Central Nervous System Lesions Relevant in Surgical Practice Today?

Crush cytology: an expeditious diagnostic tool for gastrointestinal tract malignancy

Background and study aims  Crush cytology is a simple and rapid method used for diagnosis of central nervous system lesions. We have evaluated the diagnostic accuracy of crush cytology for gastrointestinal tract lesions. Patients and methods  This was a prospective, cross-sectional, single center study, conducted on the patients who had suspected malignant lesions between August 2018 and March 2020. The crush cytologic diagnoses were correlated with histology to determine the diagnostic accuracy. Results  During the period of interest, a total of 451 patients (26.4 % esophagus & GE junction, 16.6 % stomach, 5.9 % ampulla & duodenum, and 50.9 % colorectal) had a suspected malignant lesion on endoscopic examination. Histology confirmed 92.9 % cases as malignant lesions and 7.1 % as nonmalignant. On crush cytology, 84.5 % were positive for malignancy, 8.9 % were negative for malignancy and 6.6 % were reported as suspicious for malignancy. The overall sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of crush cytology were 97.3 %, 90 %, 99.2 %, 72.5 % and 96.9 %, respectively. Conclusions  Crush cytology is a highly sensitive, specific, rapid and cost effective technique to diagnose gastrointestinal malignancies in endoscopically suspected malignant lesions. However, it cannot entirely substitute histopathological examination for definite tumor typing, grading, confirming invasion and in cases in which cytology is suspicious. Crush cytology is an added asset to the histology to maximize diagnostic accuracy and accelerating decision making for the management of lesions.

Intraoperative squash cytology provides a qualitative intraoperative diagnosis for cases in which frozen section yields a diagnosis of equivocal brain tumour

OBJECTIVE

We assessed whether intraoperative squash cytology could provide surgeons with a qualitative diagnosis of brain lesions when frozen section diagnosis is equivocal.

METHODS

The study included 51 lesions that were diagnosed intraoperatively as equivocal brain tumour on the basis of frozen section. We retrospectively classified the lesions into five groups according to the final histopathological diagnoses (I: malignant lymphomas; II: diffuse astrocytic and oligodendroglia tumours; III: pituitary adenomas, IV: metastatic carcinomas; V: others). We assessed the squash cytology features of Groups I-IV and of the specific lesion types, and compared features among the groups.

RESULTS

The four groups differed in a range of salient cytomorphological features: lymphoglandular bodies in Group I (eight of nine cases), cytoplasmic fibrillary processes in Group II (six of eight cases), low-grade nuclear atypia in Group III (seven of seven cases), and large nuclei (approximately 80 μm² ) and nuclear crush artefacts in Group IV (seven of nine cases).

CONCLUSION

Findings of lymphoglandular bodies on intraoperative squash cytology can be considered characteristic of malignant lymphomas, while cytoplasmic fibrillary processes indicate diffuse astrocytic and oligodendroglial tumours. We conclude that squash cytology could yield a qualitative intraoperative diagnosis in over 25% of cases for which frozen section yields a diagnosis of equivocal brain tumour.