Cytologic diagnosis of pulmonary adenocarcinoma with micropapillary pattern: Does it correlate with the histologic findings?

Abstract

Micropapillary adenocarcinoma is associated with poor-prognosis in several organs including the lung. The presence of small tight balls of neoplastic cells devoid of fibrovascular core in cytological preparations (micropapillary tufts) has been described as characteristic of micropapillary adenocarcinoma. In the lung, however, this criterion has not been validated. The cytological material of 46 cases of histologically proven pulmonary adenocarcinoma with a micropapillary component was compared to 33 cases with no micropapillary component to determine the specificity of micropapillary tufts for the histologic diagnosis of micropapillary adenocarcinoma. Other histologic patterns of invasive pulmonary adenocarcinomas (acinar, papillary, and solid) were also compared with patterns of neoplastic cell aggregates in cytological preparations. There were no significant differences in the distribution of micropapillary clusters between the two groups. The positive predictive value for the cytologic diagnosis of a micropapillary component in lung adenocarcinomas was of 64%. Similar findings were observed for other invasive patterns. Therefore, the detection of micropapillary tufts in cytology is not specific for the diagnosis of a pulmonary micropapillary adenocarcinoma in the lung.

A Grading System of Lung Adenocarcinomas Based on Histologic Pattern is Predictive of Disease Recurrence in Stage I Tumors

“…It has been recently reported that there is no correlation of histologic patterns and cytologic patterns seen in aspiration biopsies of lung adenocarcinomas. 29 In core biopsies, limited sampling of the tumors may not be representative of the heterogeneity of the primary tumor. Therefore, the scoring system must be validated in these small samples or a modified scoring system that includes nuclear grade could be applied to smaller tissue samples.…”

“…In addition, we defined micropapillary pattern, which is not specified as a distinct subtype in the 2004 WHO classification, as small papillary tufts (morule-like clusters) of neoplastic cells without a fibrovascular core seen mostly as detached clusters from the surrounding tumor, similar to earlier studies. 18,29 Comprehensive histologic subtyping was performed in the primary tumor in a semiquantitative manner with the percentage of the 5 possible tumors histologic subtypes quantified in 10% increments, totaling 100% per tumor as described earlier. 21 Predominant pattern and second most predominant pattern in a mixed-type adenocarcinoma were defined as the histologic subtypes that comprised the highest and second highest percentage(s) of a particular tumor.…”

The value of cell block based on fine needle aspiration for lung cancer diagnosis

“…And reactive type II pneumocytes (RPII) undergo hyperplasia and reactive changes in response to injury resulting from various conditions, such as infections, interstitial lung diseases, organizing pneumonia, pulmonary drug toxicity, and tuberculosis (10,(15)(16)(17). A lepidic pattern of AC may be observed in small biopsy specimens but is difficult to diagnose in cytological material (18,19). In the aforementioned situations, it is challenging for cytopathologists to arrive at correct diagnoses.…”

Prognostic considerations of the new World Health Organization classification of lung adenocarcinoma

“…The most specific criteria, such as papillary structures, may not be present in a large number of samples. Much of this disagreement may be due to sampling, as secondary and tertiary patterns on resection may be overrepresented in a given small sample [8,9]. Some promising efforts to grade cytology samples suggest that prognostication may be part of future classifications [10].…”