However, clinical data will need to be taken into account before the final stage can be obtained. Only limited information can be obtained from these specimens namely a diagnosis of malignancy and the tumour classification. All the tissue should be fixed in formalin and routinely processed. Multiple sections should be cut and some left unstained for additional special histochemical and immunohistochemical procedures. The diagnosis of malignancy on these small samples is reliable but tumour classification less so.17 Classification is based on the best differentiated area and therefore undifferentiated carcinomas are much more frequent on small biopsies than larger resection specimens.
Lung tumours show marked heterogeneity which is most evident on larger tumour samples.
The important aim is to make a distinction between small and non-small cell carcinoma because treatment is different. Ishiwara S. Lymph node mapping and curability at various levels of metastases in resected lung cancer. The changing pattern of lung carcinoma. Lung carcinoma surgical pathology report adequacy. International Histological Classifications of Tumours.