Mutations in gastrointestinal stromal tumors diagnosed by endoscopic ultrasound-guided fine needle aspiration.

Gastrointestinal stromal tumors (GISTs) are characterized by overexpression and mutations of c-Kit. Approximately 80% of c-Kit mutations occur in exon 11, being a response factor to imatinib (Gleevec) therapy. We aimed to assess whether c-Kit and PDGFRA mutation analysis of GISTs obtained by endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) could be routinely performed. Mutation analysis of c-Kit hotspot exons (9, 11, 13 and 17) and PDGFRA hotspot exons (12 and 18) was performed in aspirates 51 mesenchymal tumors. We identified c-Kit mutations in 61% of GIST cases, in accordance with previously published ranges (30-90%). Nearly 95% (19/20) of c-kit-mutant tumors carried exon 11 mutations. Mutation analysis is possible in FNA cell blocks and can assist in the diagnosis and therapeutic decisions in GIST cases.

Detection of intracytoplasmic immunoglobulin by flow cytometry in B-cell malignancies.

The aim of this study was to compare the results of flow cytometric (FCM) determination of heavy and light chain cytoplasmic immunoglobulin (cIg) with those obtained by the peroxidase-antiperoxidase (PAP) method. Fifty-one patients, including five non-T-acute lymphoblastic leukemias, 16 B-chronic lymphocytic leukemias (CLL), 13 non-Hodgkin's lymphomas, seven hairy cell leukemias, four multiple myeloma/plasma cell leukemias, and six T-cell leukemia/lymphomas, as well as 12 normal controls, were studied. Saponin-permeabilized cell suspensions were indirectly stained with monoclonal antibodies and analyzed by flow cytometry. Acetone-fixed cytocentrifuge smears were stained for cIg by the PAP method. The results obtained indicate that: (a) detection of cIg by FCM is a feasible and useful technique to confirm the B-cell lineage of leukemias and lymphomas, particularly those characterized by low-density surface immunoglobulin, such as CLL; and (b) cIg detection by FCM and PAP staining are complementary methods to recognize with certainty the monoclonality of B-cell malignancies.

Detection of terminal deoxynucleotidyl transferase (TdT) by flow cytometry in leukemic disorders.

We applied a new technique to the detection of intracellular TdT in 26 leukemic patients, including 16 non-T acute lymphoblastic leukemia (ALL), four T-ALL, one T-lymphoblastic lymphoma in leukemia phase, one undifferentiated leukemia, one de novo lymphoblastic phase of chronic myeloid leukemia, and three acute monocytic leukemias (AMOL). Mononuclear cell suspensions were incubated in saponin to permeabilize the cell membrane. The cells were then stained by indirect immunofluorescence (IF) using anti-human TdT monoclonal antibodies and were analyzed by flow cytometry (FCM). The TdT results were compared with those obtained by biochemical TdT assay (26 cases), immunoperoxidase determination (PAP) (12 cases), and fluorescence microscopy (seven cases). The results obtained by PAP and fluorescence microscopy were 100% concordant with those obtained by FCM and biochemical assay. TdT determination by FCM allows the analysis of large numbers of cells in a fast, objective, and reliable manner, as compared with biochemical assay, PAP, and fluorescence microscopy determinations.

In situ DNA fragmentation assay for detection of apoptosis in paraffin-embedded tissue sections. Technical considerations.

Detection, by light microscopy, of cells in situ undergoing apoptosis has been improved by use of an in situ apoptosis (DNA fragmentation) assay on formalin-fixed and paraffin-embedded tissue sections. We studied conditions of tissue preparation and fixation that may affect the test results. In this study, we intended to determine whether archival tissues prepared under unknown conditions can be used for the in situ apoptosis assay. All tissue sections were pretreated with Proteinase K, followed by incubation with biotinylated 11-deoxyuridine triphosphate in terminal deoxynucleotidyl transferase and then avidin-biotin-peroxidase complex. The following formalin-fixed and paraffin-embedded histologic sections were tested: (1) normal tissues from surgically resected specimens fixed immediately or stored at 4 degrees C and then fixed after 1, 2, 4, 6, or 24 hours; (2) archival autopsy material from histologically normal tissues; and (3) freshly prepared normal tissues from C57 mice. We observed that fixation- and prefixation-elapsed times do not adversely affect the results of the assay. Similar, if not identical results were seen in archival human tissues stored for up to 25 years, the normal tissues freshly prepared from surgical specimens, and the tissues from C57 mice. We conclude that the in situ assay of DNA fragmentation is rapid, sensitive, and reproducible. The use of formalin-fixed and paraffin-embedded archival material as old as 25 years opens the way for a variety of studies of apoptosis in diverse pathologic states.

Tissue effects of salivary gland fine-needle aspiration. Does this procedure preclude accurate histologic diagnosis?

Recent reports have alluded to various tissue effects secondary to fine-needle aspiration (FNA), particularly infarction observed in resected salivary gland masses, precluding accurate histologic diagnosis. Our experience with the use of 25-gauge needles indicates otherwise. We retrospectively reviewed 94 resected salivary gland masses previously sampled by FNA, looking for infarction, hemorrhage, needle track tumor seeding, and fibrosis. We assessed the significance of these complications and their impact on the histologic diagnosis. The median interval from FNA to excision was 25 days. Variable degrees of infarction and hemorrhage were present in 7 cases (7%) and 9 cases (10%), respectively. Infarction ranged from 5% to 80% (average, 20%), while hemorrhage averaged less than 20% of the material on the tissue sections. Significant infarction was present in acinic cell carcinomas (3/7), but histologic diagnosis was not compromised, and tissue alterations were absent. We conclude that FNA of salivary gland lesions using 25-gauge needles is safe and does not significantly alter the histologic diagnosis. The tissue effects observed did not preclude accurate diagnostic interpretation in any case.

Sialolithiasis. Differential diagnostic problems in fine-needle aspiration cytology.

Sialolithiasis with obstruction of major salivary gland ducts can lead to clinical tumefaction related to cystic dilatation. In addition to mucus accumulation, these pseudoneoplasms feature hyperplasia and squamous metaplasia of the ductal lining epithelium, with varying degrees of inflammation. The authors report five examples of this lesion aspirated from two males and three females ranging in age from 45 to 80 years (median 65 years). Three were in the submaxillary gland, and two were in the parotid. In three cases, stone fragments were identified, and diagnoses of sialolithiasis were rendered; two of these patients underwent surgical excision. The remaining two cases showed prominent foam cells and metaplastic squamous cells in a mucoid background that mimicked low grade mucoepidermoid carcinoma. Stone fragments were not identified and a differential diagnoses of sialolithiasis versus low grade mucoepidermoid carcinoma were suggested. Surgical excision revealed sialolithiasis in both instances. When stone fragments are identified in aspirated material, these cases pose little diagnostic difficulty. However, when this material is not present, epithelial changes and mucus accumulation may be difficult to distinguish from low grade mucoepidermoid carcinoma. Cautious interpretation is suggested in this setting.

Secondary pericardial malignancies: a critical appraisal of the role of cytology, pericardial biopsy, and DNA ploidy analysis.

The authors studied 112 pericardial fluids (45 malignant, and 67 benign) from 63 men and 33 women. All cytologic (n = 112) and histologic (n = 61) specimens were reviewed. Statistical analysis was conducted in 61 paired cytology and histology specimens (45 malignant and 16 benign) and correlated with available ploidy analysis of fluid specimens (n = 34). In cases of malignancy (41 patients), the primary site was known in 34 patients, whereas no origin for metastatic disease was apparent in 3 patients. Pericardial cytology yielded the initial diagnosis in four patients. After careful review of all cytology and histology specimens, seven truly discrepant cases were noted, six of which had positive cytology. Tissue biopsy sampling error was the cause for such discrepancies. DNA diploidy obtained by flow cytometry correlated with benign cytology, whereas aneuploidy was associated with malignant cytology in a total of 32 of 34 cases (94%). Cytologically malignant effusions rendered diploid DNA in 2 of 10 cases (20%). In conclusion, cytology is the single most important parameter in the evaluation of secondary pericardial malignancy and should be considered the gold standard. Causes for false-negative cytologic diagnoses include scant cellularity and obscuring blood. Hence, careful screening is recommended. The low sensitivity of flow cytometric DNA analysis does not favor its routine use.

Basal cell (monomorphic) and minimally pleomorphic adenomas of the salivary glands. Distinction from the solid (anaplastic) type of adenoid cystic carcinoma in fine-needle aspiration.

Cytologic features of the cell-stroma interface are useful in distinguishing between monomorphic adenomas of the basal cell type and adenoid cystic carcinoma. In basal cell adenomas, the collagenous stroma interdigitates with adjacent cells, whereas in adenoid cystic carcinoma, the two are separated by a sharp smooth border. Furthermore, the stroma of basal cell adenomas can contain rare spindle cells or capillaries, but the cylinders of adenoid cystic carcinoma are acellular. The authors review their experience with five cases of basal cell adenoma, and three cases that were designated "minimally pleomorphic adenomas." The latter group showed the small blue cell pattern of basal cell adenoma at the time of fine-needle aspiration, and histology revealed only small foci of typical pleomorphic adenoma. With the exception of one cystic case, the cell-stroma interface of basal cell adenoma was observed in all eight cases. These cases are contrasted with three adenoid cystic carcinomas with extensive solid (anaplastic) areas. All showed the small blue cell pattern and cell-stroma interface features of basal cell adenoma. Neither showed the smooth-bordered cylinders of adenoid cystic carcinoma. Two of these three were incorrectly interpreted as benign at the time of fine-needle aspiration. The authors suggest that the stroma aspirated from solid adenoid cystic carcinoma represents desmoplastic tumor stroma that mimics the pattern of basal cell adenoma in smear material. Distinction between basal cell adenoma and the solid type of adenoid cystic carcinoma at the time of fine-needle aspiration remains a very difficult problem.

Cytologic findings in thyroglossal duct carcinoma.

Approximately 150 cases of thyroglossal duct carcinoma, predominantly of the papillary type, have been reported, but the preoperative fine-needle aspiration (FNA) diagnosis of such neoplasms has rarely been cited. The authors describe FNA findings in four samples obtained from three patients who were 29, 50, and 83 years of age, histologically diagnosed as papillary (n = 2) and squamous (n = 1) thyroglossal duct carcinomas. Atypia and squamous cell carcinoma were the FNA diagnoses in the patients with papillary carcinomas. The remaining case was correctly diagnosed as keratinizing squamous cell carcinoma. Cellularity was scant in two cases and moderate in one, and all displayed a cystic background. The authors also reviewed FNA features in 11 papillary and 2 Hurthle cell carcinomas from the English language literature; diagnostic findings were present in less than one third of the cases. In conclusion, familiarity with the FNA findings of thyroglossal duct carcinoma is limited by its rarity. The presence of large, atypical squamous cells, or psammoma bodies, in the FNA material of a midline anterior cystic neck mass should suggest papillary thyroglossal duct carcinoma.

Diagnostic value of brush cytology in the diagnosis of duodenal, biliary, and ampullary neoplasms.

Endoscopy is a valuable tool in the diagnosis and management of duodenal lesions and biliary strictures. We assessed the value of cytology in the evaluation of these lesions and analyzed the causes of discrepancy among clinical, histologic, and cytologic parameters. The study included 118 patients with duodenal ulcers, ampullary neoplasms, or biliary strictures who were examined between 1975 and 1995; 120 cytologic examinations were performed. The specimens included brushings of the duodenum (DB, n = 50), ampulla (AB, n = 32), and biliary ducts (BB, n = 38). Endoscopic biopsies performed concurrently included the duodenum (n = 37), the ampulla (n = 22), and the biliary ducts (n = 23). Comparison of cytologic and histologic results showed the following sensitivity and specificity: DB, 40% and 97%, respectively; AB, 100% each; BB, 75% and 93%, respectively. The DB, AB, and BB revealed malignant neoplasms in 2 of 5, 7 of 7, and 6 of 8 cases, respectively. Twenty-three duodenal neoplasms were diagnosed by either modality and included 11 adenocarcinomas, 9 villous tumors, 2 metastatic renal cell carcinomas, and 1 large cell non-Hodgkin's lymphoma. Endoscopic brush cytology is an effective means of diagnosing ampullary neoplasms, and it complements tissue biopsy in cases of bile duct stricture. Location, predominance of tumor-induced stroma, an extramucosal growth pattern, sampling error, and interpretative experience influence the diagnostic evaluation. Cytologic diagnosis of an adenoma does not exclude an underlying malignant neoplasm in ampullary tumors. In some instances, it may be difficult to distinguish between villous tumors with severe dysplasia and adenocarcinomas by cytology alone.

Fine needle aspiration cytology of papillary neoplasms.

This article covers the fine needle aspiration biopsy cytomorphology of papillary carcinomas of different organs, differential diagnoses, and clinical correlation. Diagnostic problems and helpful cytologic features are emphasized. The purpose is to have a concise source of information that helps the pathologist to evaluate these neoplasms.

Intravascular lymphomatosis with bone marrow involvement.

We describe the case of a 56-year-old man who presented with numbness and tingling of the extremities, weakness, and fatigue. Laboratory findings included anemia and thrombocytopenia. A diagnosis of intravascular lymphomatosis was established when liver, omentum, and bone marrow samples were examined. A review of the literature reveals that most cases of intravascular lymphomatosis have cytopenias, mainly anemia and thrombocytopenia, but bone marrow involvement is rare. In our case, a subtle neoplastic infiltrate in the marrow sinusoids was highlighted with a B-cell marker. While immunohistochemical analysis was not performed in most reported cases in the literature, our studies suggest that a systematic search in bone marrow of cases of intravascular lymphomatosis may reveal unsuspected neoplastic cells. We conclude that bone marrow involvement in intravascular lymphomatosis appears to be rare, has subtle features, and is difficult to diagnose if unsuspected and not searched for.

Q-switched neodymium:yttrium-aluminum-garnet laser treatment of lentigo maligna.

Lentigo maligna is a premalignant lesion of atypical melanocytes that typically arises on the head and neck of elderly patients. It is considered a melanoma in situ with a significant risk for transformation to invasive lentigo maligna melanoma. Surgery is the preferred method of treatment; however, because of the advanced age of the typical patient with lentigo maligna, the frequency of complicating medical problems, and the cosmetic or functional aspects of treatment, surgical excision is not always feasible. The purpose of this pilot study was to evaluate the efficacy and safety of Q-switched neodymium:yttrium-aluminum-garnet laser treatment of lentigo maligna. Eight patients were treated with 532 and/or 1064 nm wavelengths from the laser. All patients showed a response to laser therapy, and 2 patients treated with 1 treatment from each wavelength had complete eradication of the LM, with no evidence of recurrence in 42 months. Further study is warranted, but Q-switched neodymium:yttrium-aluminum-garnet laser is a promising alternative treatment for lentigo maligna.

Benign spindle and inflammatory lesions of the breast: diagnosis by fine-needle aspiration.

We describe fine-needle aspiration (FNA) findings in 7 patients with breast masses showing numerous spindle cells in smear material. The benign nature of these lesions was confirmed by clinical follow-up (n = 4) or surgical excision with histologic examination (n = 3). The final diagnosis included one case each of myofibroblastoma, juvenile hypertrophy, post-FNA reactive stromal proliferation, stromal induction in proliferative fibrocystic disease, and subareolar abscess. There were two instances of granulation tissue. The case of stromal induction was initially felt to be suspicious for phyllodes tumor. The post-FNA stromal reaction was considered sufficiently atypical to warrant histologic investigation. The importance of historical and physical examination findings in accurate interpretation of these uncommon cases is emphasized. Some will require histologic assessment for final diagnosis.

Subcutaneous masses of the scalp and forehead: diagnosis by fine-needle aspiration.

We report our cytologic findings and clinical correlations in benign (N = 2) and malignant (N = 16) subcutaneous masses of the scalp (N = 15) and forehead (N = 3), studied by fine-needle aspiration (FNA). Diagnoses were divided in 3 groups: (1) Scalp plasmacytoma (as a manifestation of multiple myeloma) (6 cases) was the most frequent diagnosis. In one patient it was the presenting manifestation of the disease. (2) Miscellaneous malignancies included 8 carcinomas, 1 melanoma, and 1 malignant lymphoma. The scalp or forehead mass was the initial presentation and FNA was the initial diagnostic approach in five patients. (3) A single case each of pilar-type keratinous cyst and hematoma were the only benign masses encountered. In conclusion, a significant number of subcutaneous masses of the scalp or forehead represent metastatic or systemic malignancies, and they may be the initial manifestation of the disease. Rapid and accurate diagnosis by FNA provides guidelines for appropriate therapy, especially in those patients who present with advanced disease.

Fine-needle aspiration cytology findings in 214 cases of nonparotid lesions of the head.

The use and limitations of fine-needle aspiration (FNA) of lesions of the parotid gland are known, but those of nonparotid lesions of the head have been described only sporadically. We conducted this study to evaluate the utility of FNA and to analyze the causes of diagnostic discrepancies for these lesions. A total of 6,898 FNAs of different sites was performed at our institutions between January 1991-August 1998, and 214 (3.1%) of the cases were FNAs of nonparotid lesions of the head. The most common diagnosis of nonparotid lesions was squamous-cell carcinoma, in 22% (n = 48), and the most common site aspirated was the scalp, in 34% (n = 73). Lipomas and keratinous cysts comprised 5% (n = 9) of the total. A statistical analysis was conducted on 98 paired cytology and histology (n = 83) and cytology and flow cytometry (n = 15) specimens (70 malignant and 28 benign). FNA recognized the malignant and benign nature of the lesion in 60 and 26 cases, respectively with 86% sensitivity 93% specificity and 88% accuracy. Causes of false-negative FNA diagnoses (n = 10) included sampling error (n = 6), bloody smears with scant cellularity (n = 3), and bland cytomorphology (n = 1). Florid granulation tissue and a mucocele of the tongue accounted for the two false-positive cases. We conclude that FNA is an effective tool for triage of surgery candidates with nonparotid lesions of the head. Adequate samples with sufficient cellularity are required for avoiding false-negative diagnoses. Occasionally, tissue biopsy is needed for diagnosis of equivocal cases.

Fine-needle aspiration cytology of mucous retention cyst of the tongue: distinction from other cystic lesions of the tongue.

Mucous retention cyst (MRC) is a common submucosal lesion of the oral cavity that, when deeply seated, simulates a neoplasm. This report describes the fine-needle aspiration cytology findings of a lingual MRC of complex architecture and with metaplastic epithelium. In addition, we emphasize its cytologic differential diagnosis from other benign and malignant cystic lesions of the tongue. To the best of our knowledge, this is the first report of aspiration cytology of a complex MRC of the tongue.

Detached single cilia: another potential pseudomicrobe seen in bronchoalveolar lavage specimens.

High magnification examination of Romanovsky-stained bronchoalveolar lavage (BAL) material may be needed, if one is to confidently exclude small organisms such as toxoplasmosis, histoplasmosis, and the negative images of mycobacteria. Pseudomicrobes have been described, and detailed criteria must be carefully applied, if incorrect diagnoses are to be avoided. We recently noted numerous free-lying, uniform, eosinophilic, straight or slightly curved bacilliform structures in such a specimen. These were seen on Diff-Quik-stained material, but were extremely pale on Papanicolaou-stained slides. Comparison with the cilia of contaminating bronchial cells showed these pseudomicrobes to have similar length, diameter, and tinctorial properties. Electron microscopy of the sedimented cell pellet showed isolated, detached single cilia (DSC) far removed from any bronchial cells. Twenty BAL's from 13 males and seven females (median age = 48.5) undergoing infection surveillance were then retrospectively reviewed. DSC were present in 16 specimens (80%), but were rare in three of these. Although present in cases with prominent bronchial cell contamination (n = 6 cases), DSC were also encountered when ciliated cells were rare (n = 13), or absent (n = 1). Familiarity with these distinctive structures should make it unlikely that they will be mistaken for infectious organisms.

Cytology of suture granulomas in post-hysterectomy vaginal smears.

In histologic sections, foreign body giant cells are often associated with a granulomatous reaction to embedded suture material. However, this finding is unusual in exfoliative cytology samples. We describe the cytologic findings associated with suture granulomas in nine vaginal smears obtained from four women, ages 53 to 72. The patients had undergone hysterectomy for endometrial adenocarcinoma (three patients) and cervical carcinoma in situ (one patient). Smears taken 6 to 34 mo after surgery showed a moderate to severe acute inflammatory reaction, foreign body giant cells, and polarizable suture material. A vaginal cuff biopsy from one patient confirmed the diagnosis. Although multinucleated giant cells in postmenopausal vaginal smears are usually a non-specific finding, phagocytosed refractile material observed post hysterectomy may reflect a chronic tissue reaction to suture material. The presence of an acute inflammatory reaction, foreign body type giant cells, and the appropriate past surgical history, should prompt the pathologist to rapidly screen the slide under polarized light to evaluate the possibility of suture granulomas.

Papillary neoplasms of the breast: fine-needle aspiration findings in cystic and solid cases.

Papillary neoplasms of the breast are uncommon; at the time of needle aspiration, the diagnostic yield from such lesions can be initially classified as cystic or solid. We describe the fine-needle aspiration findings in four cystic papillary neoplasms (three intracystic papillary carcinomas and one intracystic papilloma) and three solid masses (two sclerosing ductal lesions and one infiltrating ductal carcinoma with prominent papillary component). The smears were examined with respect to the following features: cellularity, architectural pattern in cell groups, cytologic pleomorphism, degree of cohesiveness, morphology and size of individual cells, anisonucleosis, nuclear-cytoplasmic ratio, irregularity of nuclear contour, chromatin texture, macronucleoli, the presence of bipolar nuclei, apocrine cells, and multinucleated giant cells. A combination of cytologic and clinical characteristics may be helpful in distinguishing benign from malignant papillary lesions.