Benign Reactive Proliferations vs. Malignancy
One of the most frequent questions at frozen section of pleural tissue is whether or not a pleural lesion is benign or malignant. Differentiating benign reactive mesothelial hyperplasia or organizing pleuritis from a malignancy on frozen section may be a more difficult and a more immediately important differential than determining the type of cancer that a patient has on frozen section (Figs. 6.1-6.3). Immediate treatment decisions by the surgeon may depend on the frozen section diagnosis of benign reactive process vs. malignancy as discussed in the “Introduction” of Chap. 1. Conditions associated with benign reactive mesothelial hyperplasia and organizing pleuritis are listed in Table 6.1. As discussed in the “Introduction” of Chap. 1, reactive, inflammatory processes can potentially produce clinical, radiographic, gross, and microscopic features that mimic those of malignancy (Figs. 6.4-6.10).