Cytological diagnosis of sarcoidosis revisited: A state of the art review

Abstract

Diagnosis of sarcoidosis has never been an easy task. This is primarily because there is no single diagnostic test that can clinch the diagnosis. Demonstration of granulomas remains an essential criteria, but as granulomatous inflammation can be seen in host of conditions, it is necessary to exclude all possible causes, as well as to correlate with other findings, before arriving at the diagnosis of sarcoidosis. Cytology has been used effectively since the last few decades in demonstration of granulomas in various organs. Recent developments in various fields of cytodiagnosis of sarcoidosis including transesophageal ultrasound-guided fine-needle aspiration and endobronchial ultrasonograpy-guided transbronchial needle aspiration have revolutionized this field. These techniques are safe, minimally invasive, and give real-time information during aspiration. In comparision to the conventional methods, these allow easier sampling and have better sensitivity. In addition to these methods, a variety of ancillary techniques are also utilized and are reviewed here.

Rapid cytological analysis of endobronchial ultrasound-guided aspirates in sarcoidosis

“…Some studies have used cytopathologists for EBUS-TBNA with ROSE [10,13,14] in patients with suspected sarcoidosis, but did not utilise the diagnostic information to enable a decision to be made not to proceed to TBLB. This study confirms a growing body of evidence in recent years that shifts the paradigm from the primacy of histology in the diagnosis of sarcoidosis to the importance of cytological assessment [24]. Fine-needle cytology is still underutilised in the diagnosis of sarcoidosis [25].…”

Nodular lymphocyte‐predominant Hodgkin lymphoma

“…FNA is increasingly being used in the assessment of lymphadenopathy to spare patients from a potentially unnecessary, invasive excisional biopsy. Its usefulness in the diagnosis of infectious processes, sarcoidosis, and common types of NHL have been well documented 8‐11. In several rarer types of lymphoma, however, cytomorphologic features are not well described.…”

Cell Block Examination Is Critical for Sarcoidosis Diagnosis by Endobronchial Ultrasound-Guided Mediastinal Lymph Node Fine Needle Aspiration

“…Currently, the diagnosis of sarcoidosis is established when there is compatible clinical/radiological evidence together with morphological confirmation. 2,3 The only clinical situation when diagnosis of sarcoidosis can be made reliably without biopsy is Lofgren syndrome due to its distinct presentation of combined hilar lymphadenopathy, erythema nodosum on the shins, arthritis and fever. 15 A number of bronchopulmonary specimens and diagnostic app ro aches have b een used fo r sar co id o sis tissue confirmation with variable success rates.…”

“…1 Although the etiology of this granulomatous disease remains unknown, current knowledge suggests it results from disordered immune regulation in genetically predisposed individuals after exposure to certain environmental agents. 2 Tissue confirmation, together with clinical and radiological suspicion, is an integral part of sarcoidosis diagnosis. 3 The morphological characteristics of sarcoidosis include nonnecrotizing granuloma as well as exclusion of similarly presenting diseases such as tuberculosis, fungal infection, lymphoma, and metastatic carcinomas.…”