The role of fine-needle aspiration biopsy in the diagnosis of malignant tumors

Abstract

Cytopathology and histopathology play a key role in the process of diagnosing oncological diseases and premalignant conditions. Fine-needle aspiration (FNA) is one of the techniques used for obtaining biopsy of a wide variety of body tissues, causing patients minimal discomfort. Therefore, it is often considered to be the best strategy for investigating and diagnosing some precancerous or potential malignant lesions. Being successful as a means of confirming the clinical suspicion of metastatic recurrence in the cases of an already known cancer, the interest has further focused on the preliminary diagnosis of various types of benign or malignant tumors. In cases of inoperable tumors, this technique is useful for formulating the final diagnosis. FNA biopsy proved its effectiveness as a highly accurate, cost-effective, and safe technique, with potential high diagnostic yield. Immunohistochemistry, used as an additional tool to classical histopathological examination, remains a very practical and reliable technique that promises good results especially in determining the site of origin within metastatic disease.

Figure 1

The distribution frequency of the sampling site

Figure 2

The share of sites in inadequate sample cases

Figure 3

The share of malignant and non-malignant from the adequate samples analyzed

Figure 4

The share of positive and negative markers used for immunohistochemistry (IHC) examination

Figure 5

The share of cases where IHC markers were helpful to specify the origin of metastasis

Figure 6

Immunohistochemical staining of metastatic tumors in diverse sites: (A) Micrograph with GATA3 nuclear immunostaining (×400) highlighting clusters of ECs in a patient with metastatic BC to the pleura (GATA3 is a nuclear marker, more sensitive than GCDFP-15 or mammaglobin for metastatic BC immunostaining); (B) Clusters of ECs with moderate ER nuclear expression (×200) in a patient with metastatic BC to the mediastinal tissue (ER is used by pathologists in BC, to predict response to Tamoxifen or other anti-estrogens; it is relatively specific for breast origin in metastatic sites); (C) CDX2 immunostaining (×200) highlighting ECs in a patient with metastatic gastric carcinoma to the peritoneum (CDX2 is a fairly specific marker of gastrointestinal origin for adenocarcinoma; it can be used to determine origin of metastatic carcinoma as part of a panel); (D) NKX3.1 nuclear immunostaining (×400) highlighting cluster of ECs in a patient with metastatic prostate carcinoma to the vertebra; (E) Clusters of ECs with incomplete HER2 membrane immunostaining (×200) in a patient with metastatic BC to the mediastinal tissue [HER2 testing must be performed on every primary invasive carcinoma and on a metastatic site (if stage IV); anti-HER2 therapy (Trastuzumab/Herceptin) plus chemotherapy reduces recurrence, metastases and mortality in HER2 gene amplified BC patients; anti-HER2 therapy may improve survival in metastatic disease]; (F) TTF-1 nuclear immunostaining (×200) highlighting ECs in a patient with metastatic lung adenocarcinoma to the mediastinal tissue. BC: Breast carcinoma; CDX2: Caudal-type homeobox 2; ECs: Epithelial cells; ER: Estrogen receptor; GATA3: GATA-binding protein 3; GCDFP-15: Gross cystic disease fluid protein-15; HER2: Human epidermal growth factor receptor 2; TTF-1: Thyroid transcription factor-1