Fine-needle aspiration cytology diagnosis of metastatic gastrointestinal stromal tumor in the liver: a report of three cases

A Clinical case of Duodenal Gastrointestinal Stromal Tumor with a Peculiarity in the Surgical Approach

We describe a case of duodenal, third portion, segmental resection for gastrointestinal stromal tumor. A 76-year-old man was referred for gastrointestinal bleeding, dyspnea and asthenia. Esophagogastroduodenoscopy showed a duodenal bleeding fistula. Computerized tomography demonstrated a retroperitoneal mass that compressed and displaced forward the third duodenal tract. Segmental resection of the third portion of the duodenum with a subtotal gastrectomy was performed. The patient was reconstructed with a termino-terminal duodenal anastomosis of the second and the fourth tract and with a Roux-en-Y gastrojejunum anastomosis. There were no postoperative complications. This duodenectomy procedure could be useful as a less extensive resection for duodenal gastrointestinal stromal tumor located in the third portion of the duodenum when the tumor is well capsulated, when the surrounding structures are not infiltrated and when there are no vascular difficulties. The technique reduces the morbidity and mortality correlated with duodenocefalopancreasectomy and improves postsurgical quality of life without worsening the risk of recurrence.

Fine needle aspiration: past, current practice and recent developments

Fine needle aspiration (FNA) is a diagnostic technique that has become widely used. The procedure may be performed by interventional radiologists, endoscopists, pathologists and cytotechnologists; diagnostic interpretation of FNA samples is performed by pathologists and cytotechnologists. I provide here an introduction to the technique and applications of FNA with a review of current practice parameters and recent developments in the molecular application of FNA.

Fine-needle aspiration biopsy of hepatic lesions: computerized tomographic-guided versus endoscopic ultrasound-guided FNA

BACKGROUND

Computerized tomographic (CT)-guided fine-needle aspiration (FNA) cytology is a well-established tool in the diagnosis of hepatic lesions. Endoscopic ultrasound-guided FNA (EUS-FNA), developed recently and used predominantly in evaluating mediastinal and pancreatic lesions, provides access to a significant portion of the liver and to perihepatic structures not readily accessible by a percutaneous approach.

METHODS

A recent experience (1997-2002) with CT-guided FNA of liver lesions at the University of Alabama Birmingham (UAB) was compared with the first 2.5 years of EUS-FNA experience (2000-2002). Cases were identified using a SNOMED search and all reports and cytologic slides were retrieved for review.

RESULTS

In 6 years, 34 percutaneous CT-FNA liver biopsies were performed at UAB; in approximately 2.5 years, 16 EUS-FNA liver biopsies were done. In both groups the primary clinical indication was suspected metastatic carcinoma (CT, 41% of cases vs. EUS, 56%). The 2 techniques yielded a similar range of benign, atypical, and malignant diagnoses (CT: 26%, 18%, and 56% vs. EUS: 19%, 25%, and 56%). Because of the clinical setting in which EUS-FNA is usually performed, a much narrower range of neoplasms was sampled by EUS-FNA. Benign gastrointestinal epithelial cells were identified in 60% of the EUS-FNA specimens.

CONCLUSIONS

Early experience suggests EUS-FNA is comparable to CT-FNA in terms of diagnostic utility for hepatic lesions. Anatomy limits EUS-FNA to only a fraction of the hepatic parenchyma, but that fraction includes the hilum and left lobe of the liver and the proximal biliary tract. The gallbladder, extrahepatic biliary system, and perihilar lymph nodes are readily accessible. Proximate high-resolution ultrasound imaging and cytopathologist involvement in the EUS-FNA process are further advantages. Awareness of artifacts inherent in EUS-FNA sampling (i.e., gut epithelial cells) can minimize a potential diagnostic pitfall.

The utility of fine-needle aspiration in the diagnosis of gastrointestinal stromal tumors: a cytomorphologic and immunohistochemical analysis with emphasis on malignant tumors

BACKGROUND

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal neoplasms of the tubular gut and mesentery. Fine-needle aspiration biopsy (FNAB) currently is a useful tool in the diagnosis of GIST because of various mutations of the KIT protooncogene that are recognized as characteristic of these tumors. Despite such advances, the malignant potential of GIST remains variable, and few studies have reported their findings in patients with malignant GIST. Therefore, in the current study, the authors have reported their experience with FNAB as a diagnostic tool in one of the largest series of malignant GISTs and have analyzed the cytomorphologic features of the tumors relative to their clinical behavior to determine which, if any, cytologic features are indicators of malignancy.

METHODS

All patients with histologically confirmed GIST who were diagnosed by image-guided FNAB and confirmed with positive CD117 staining from 1998 to 2003 were included in the study. All tumors were reviewed for various cytomorphologic features. For study purposes, the patients were divided into two groups: Group A included all patients with malignant tumors, defined as those with metastatic disease or recurrent disease after adequate surgery with or without chemotherapy; Group B included all other patients.

RESULTS

In total, 26 tumors from 23 patients (8 males and 15 females) with a mean age of 60.9 years were available for review. There were 14 primary tumors, 7 metastases (to the liver), and 5 recurrences. Twenty-one tumors were unequivocally malignant and were placed into Group A; the remaining 5 tumors were placed into Group B. The tumors in both groups were characterized by spindled or epithelioid cells with minimal nuclear atypia or pleomorphism and a moderate amount of cytoplasm. None of the cytologic features that were evaluated could distinguish reliably between benign tumors and malignant tumors, as expected. However, on cytologic examination, all tumors that demonstrated mitoses (n = 7 tumors) and/or pretreatment necrosis (n = 3 tumors) were identified as malignant.

CONCLUSIONS

FNAB remains a reliable method for the diagnosis of GIST. Immunohistochemical staining of cytologic material with CD117 has been reliable in establishing this diagnosis by FNAB, provided adequate tissue is procured. In the current study, the presence of necrosis or mitoses in cytologic specimens was correlated with a diagnosis of malignant GIST.

Mast cells and c-Kit expression in liver allograft rejection

AIMS

The pathogenesis of rejection following liver transplantation is not fully understood. It has been postulated that mast cells may play a role in acute and chronic rejection of a number of other solid organ grafts. The aim of this study was to assess the possible role of mast cells and c-Kit+ cells in acute and chronic liver allograft rejection.

METHODS AND RESULTS

Biopsy specimens from (i) 'time zero' grafts with a minimal degree of perfusion injury (controls), (ii) transplanted livers with different grades of acute rejection, and (iii) transplanted livers with end-stage chronic rejection, were stained immunohistochemically using monoclonal anti-mast cell tryptase and polyclonal anti-c-Kit antibodies. Tryptase- and c-Kit-positive cell densities were assessed by image analysis. Tryptase-positive mast cell densities (P<0.001) were strongly correlated with acute liver allograft rejection grades and chronic liver allograft rejection. Furthermore, a similarly strong relationship was found between c-Kit+ cell densities and increasing rejection grade (P<0.001).

CONCLUSIONS

Tryptase- and c-Kit-positive mast cells form part of the inflammatory infiltrate in both acute and chronic liver allograft rejection, and may be important effector cells in these processes.

Fine needle aspiration biopsy of the liver: Algorithmic approach and current issues in the diagnosis of hepatocellular carcinoma

The role of fine needle aspiration biopsy (FNAB) in the evaluation of focal liver lesions has evolved. Guided FNAB is still useful to procure a tissue diagnosis if clinical, biochemical and radiologic findings are inconclusive. Major diagnostic issues include: (i) Distinction of benign hepatocellular nodular lesions from reactive hepatocytes, (ii) Distinction of well-differentiated hepatocellular carcinoma (WD-HCC) from benign hepatocellular nodular lesions, (iii) Distinction of poorly differentiated HCC from cholangiocarcinoma and metastatic carcinomas, (iv) Determination of histogenesis of malignant tumor, and (v) Determination of primary site of origin of malignant tumor. This review gives a general overview of hepatic FNAB; outlines an algorithmic approach to cytodiagnosis with emphasis on HCC, its variants and their mimics; and addresses current diagnostic issues. Close radiologic surveillance of high-risk cirrhotic patients has resulted in the increasing detection of smaller lesions with many subjected to biopsy for tissue characterization. The need for tissue confirmation in clinically obvious HCC is questioned due to risk of malignant seeding. When a biopsy is indicated, core needle biopsy is favored over FNAB. The inherent difficulty of distinguishing small/early HCC from benign hepatocellular nodular lesions has resulted in indeterminate reports. Changing concepts in the understanding of the biological behavior and morphologic evolution of HCC and its precursors; and the current lack of agreement on the morphologic criteria for distinguishing high-grade dysplastic lesions (with small cell change) from WD-HCC, have profound impact on nomenclature, cytohistologic interpretation and management. Optimization of hepatic FNAB to enhance the yield and accuracy of diagnoses requires close clinicopathologic correlation; combined cytohistologic approach; judicious use of ancillary tests; and skilled healthcare teams.