Category I: Nondiagnostic
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The Papanicolaou Society for Cytopathology guidelines for respiratory cytology recommend six categories with strict definitions, criteria, and associated malignancy risks. The nondiagnostic category is the first of these and comprises a group of specimens assigned to this category either because they are qualitatively or quantitatively inadequate to render a specific diagnosis or display such significant artifactual change that an accurate diagnosis cannot be rendered. Precise adequacy criteria vary depending on specimen type but for certain specimen types remain elusive. Adequacy assessment for sputum cytology depends on the presence of deep cough pigment-laden macrophages or a minimum volume of sputum necessary to prepare two to four slides. Clearly the number of cases assigned to the nondiagnostic category will vary depending on the criterion utilized and neither guarantees adequate sampling of a nodule detected on imaging studies. Criteria are best developed for EBUS (endobronchial ultrasound guided) fine-needle aspirates of well-defined pulmonary nodules. Cellularity alone is not a criterion for adequacy as some acellular specimens composed predominately of stoma or amyloid are diagnostic, while highly cellular specimens containing only benign respiratory epithelium in the presence of a distinct pulmonary nodule are judged nondiagnostic.
Definitionally, a nondiagnostic specimen is one which provides no useful diagnostic information about the pulmonary nodule, cyst, or mass lesion seen on imaging studies. In a given specimen, any degree of cellular atypia which is recognized as beyond that clearly consistent with changes associated with inflammation or repair excludes an interpretation of nondiagnostic for that sample.
Nondiagnostic specimens include those that contain only normal ciliated respiratory epithelium, non-ciliated bronchiolar epithelium, pneumocytes, and/or macrophages when a distinct pulmonary nodule is identified on imaging studies.
Nondiagnostic aspirates may also contain structures present deeper in the bronchial wall, for example, cartilage. Non-specific negative findings do not exclude a malignancy.
Specimens containing only normal-appearing ciliated respiratory epithelium, non-ciliated bronchiolar epithelium, and pneumocytes may be considered adequate only when a vague ill-defined abnormality or consolidation is detected on imaging studies.
Clinical correlation and correlation with imaging findings are a necessary component of adequacy assessment.
KeywordsAdequacy Nondiagnostic Sputum EBUS-FNA Sampling Imaging Clinical Cytology Respiratory Pulmonary Malignancy risk
- 1.Koss LG. Histology and cytology of the normal respiratory tract. In: Koss LG, editor. Diagnostic cytology and its histopathologic basis. 3rd ed. Philadelphia: JB Lippincott Company; 1979;549.Google Scholar
- 4.Alsharif M, Andrade RS, Groth SS, Stelow EB, Pambuccian SE. Endobronchial ultrasound-guided transbronchial fine-needle aspiration: the University of Minnesota experience with emphasis on usefulness, adequacy assessment, and diagnostic difficulties. Am J Clin Pathol. 2008;130(3):434–43.CrossRefGoogle Scholar