Fine needle aspiration cytology of malignant melanoma of soft parts. Report of two cases

Two cases of malignant melanoma of soft parts were diagnosed by fine needle aspiration (FNA) biopsy. One case involved the right thumb of a 22-year-old woman; the other involved a submental mass in a 36-year-old man who had been previously diagnosed as having malignant melanoma of soft parts. The FNA smears showed discohesive polygonal or oval and fusiform cells with eccentric nuclei, irregular nuclear chromatin and prominent nucleoli. FNA cell block sections contained polygonal or fusiform cells with clear cytoplasm, eccentrically placed nuclei and prominent nucleoli. Ultrastructural and immunocytochemical studies on aspirated material supported the diagnosis of malignant melanoma.     

Heat-induced morphological and biochemical changes in the nuclear lamina from Ehrlich ascites tumor cells in vivo

Membrane-depleted nuclei from Ehrlich ascites tumor (EAT) cells isolated at low ionic strength in the presence of EDTA exhibit highly decondensed chromatin fibers and a loss of morphologically identifiable nucleoli. Treatment of these nuclei with nucleases and 2 M NaCl followed by low-speed centrifugation permitted the facile isolation of the nuclear lamina layer. Under the same conditions, but after heat-shock treatment of the living cells, the chromatin appears in a more condensed state, the nucleoli are well-defined, and the nuclear lamina layer was destabilized in concert with the appearance of an internal nuclear matrix and nucleolar skeleton. Furthermore, we also found both an increase in the protein mass as well as the appearance of a relatively large number of new proteins in this fraction, which are phosphorylated. The major proteins of the nuclear lamina, the lamins, and the residual vimentin remained insoluble. These heat-shock-induced changes were also accompanied by a dephosphorylation of lamins A and C but not of lamin B.     

Metanephric adenoma vs. Wilms' tumor: a report of 2 cases with diagnosis by fine needle aspiration and cytologic comparisons

BACKGROUND: Metanephric adenoma (MA) is a rare benign renal neoplasm that can occur at any age, whereas, Wilms' tumor (WT) is the most common malignant renal neoplasm in children and is occasionally seen in adults. CASES: In case 1, a 26-year-old male had a left renal mass. Fine needle aspiration (FNA) showed 3-dimensional sheets of cells with nuclear overlapping, molding, irregular nuclear membrane and distinct nucleoli. Frequent mitotic figures could be seen. The cytologic differential diagnosis included Wilms' tumor, neuroectodermal tumor and metanephric adenoma. Nephrectomy revealed Wilms' tumor. In case 2, a 24-year-old female presented with erythrocytosis and a right renal mass. FNA showed small, uniform cells with smooth nuclear membrane, fine chromatin and inconspicuous nucleoli. A diagnosis of metanephric adenoma was made and confirmed on nephrectomy. CONCLUSION: Differentiating MA from WT based on cytologic features on FNA biopsy prior to surgical resection can he difficult.     

The condensin complex is essential for amitotic segregation of bulk chromosomes, but not nucleoli, in the ciliate Tetrahymena thermophila

The macronucleus of the binucleate ciliate Tetrahymena thermophila contains fragmented and amplified chromosomes that do not have centromeres, eliminating the possibility of mitotic nuclear division. Instead, the macronucleus divides by amitosis with random segregation of these chromosomes without detectable chromatin condensation. This amitotic division provides a special opportunity for studying the roles of mitotic proteins in segregating acentric chromatin. The Smc4 protein is a core component of the condensin complex that plays a role in chromatin condensation and has also been associated with nucleolar segregation, DNA repair, and maintenance of the chromatin scaffold. Mutants of Tetrahymena SMC4 have remarkable characteristics during amitosis. They do not form microtubules inside the macronucleus as normal cells do, and there is little or no bulk DNA segregation during cell division. Nevertheless, segregation of nucleoli to daughter cells still occurs, indicating the independence of this process and bulk DNA segregation in ciliate amitosis.     

Arias-Stella atypia in a paratubal cyst: a rare phenomenon with potential diagnostic pitfalls

BACKGROUND: Arias-Stella reaction is commonly encountered in the endometrium during the gestational period and puerperium. Similar changes in the tubal epithelium are exceedingly rare. The cytologic findings of this phenomenon have never been described before. CASE: Cytologic findings of Arias-Stella changes in the lining cells of a left paratubal cyst in a 41-year-old woman were examined. The smears showed occasional small clusters or isolated tubal epithelial cells consisting of a mixture of ciliated and secretory cells. Some of the ciliated cells showed a marked increase in nuclear and cytoplasmic volume and possessed coarse chromatin, prominent, angulated nucleoli, dense, amphophilic cytoplasm; and a discrete cell membrane. The nuclear membrane was still thin and regular, and these cells were mitotically inactive. The preservation of apical cilia in some of them ensured their benign nature. In some areas, clusters of secretory cells with an increase in both nuclear and cytoplasmic volume and ample, clear cytoplasm were also found. There were small, monolayered sheets of regular and benign-looking epithelial cells with a honeycomb arrangement, suggesting that the Arias-Stella atypia was focal. CONCLUSION: In view of the presence of scattered giant cells with coarse chromatin and angulated macronucleoli, a false positive cytologic diagnosis of malignancy can be made if one does not pay attention to the coexistence of apical cilia and other subtle changes, including the usual nuclear/cytoplasmic ratio, thin and regular nuclear membrane and absence of mitotic activity.     

Ultrastructural organization of carcinoma Lewis (3LL) cells during cisplatin resistance formation

The electron-microscopic analysis of the morphological status of 3LL (Lewis) carcinoma tumour cells in the process of cisplatin resistant phenotype formation has been performed. It was shown that selection of tumour cells forming cell clones characterized by more complicated nuclear and cytoplasm organization took place. The tumour cells had the diffused nuclear chromatin; nuclear envelope had the numerous pores with expanded diaphragms. The prominent nucleoli consisted of the active centres surrounded by considerable areas of the condensed nucleolar chromatin. Cell cytoplasm contained the well-developed Goldgi complex and the numerous well-structured myelinoid formations in the form of dense-wrapped concentric membrane structures. The obtained data can morphologically confirm the hypothesis of Gately D.P. and Howel S.B., 1993, thain the process of resistant phenotype formation the tumour cells can create the cellular mechanisms to remove the drug from the cell and to correct the damages of the cellular nucleus and cytoplasm.     

Chromatin motion is constrained by association with nuclear compartments in human cells

BACKGROUND: In comparison with many nuclear proteins, the movement of chromatin in nuclei appears to be generally constrained. These restrictions on motion are proposed to reflect the attachment of chromatin to immobile nuclear substructures. RESULTS: To gain insight into the regulation of chromosome dynamics by nuclear architecture, we have followed the movements of different sites in the human genome in living cells. Here, we show that loci at nucleoli or the nuclear periphery are significantly less mobile than other, more nucleoplasmic loci. Disruption of nucleoli increases the mobility of nucleolar-associated loci. CONCLUSIONS: This is the first report of distinct nuclear substructures constraining the movements of chromatin. These constraints reflect the physical attachment of chromatin to nuclear compartments or steric impairment caused by local ultrastructure. Our data suggest a role for the nucleolus and nuclear periphery in maintaining the three-dimensional organization of chromatin in the human nucleus.     

Chromatin position in human HepG2 cells: Although being non-random,significantly changed in daughter cells

Mammalian chromosomes occupy chromosome territories within nuclear space the positions of which are generally accepted as non-random. However, it is still controversial whether position of chromosome territories/chromatin is maintained in daughter cells. We addressed this issue and investigated maintenance of various chromatin regions of unknown composition as well as nucleolus-associated chromatin, a significant part of which is composed of nucleolus organizer region-bearing chromosomes. The photoconvertible histone H4-Dendra2 was used to label such regions in transfected HepG2 cells, and its position was followed up to next interphase. The distribution of labeled chromatin in daughter cells exhibited a non-random character. However, its distribution in a vast majority of daughter cells extensively differed from the original ones and the labeled nucleolus-associated chromatin differently located into the vicinity of different nucleoli. Therefore, our results were not consistent with a concept of preservation chromatin position. This conclusion was supported by the finding that the numbers of nucleoli significantly differed between the two daughter cells. Our results support a view that while the transfected daughter HepG2 cells maintain some features of the parental cell chromosome organization, there is also a significant stochastic component associated with reassortment of chromosome territories/chromatin that results in their positional rearrangements.     

Fine needle aspiration cytologic findings of breast mucinous neoplasms: differential diagnosis between mucocelelike tumor and mucinous carcinoma

OBJECTIVE: To report the cytologic findings of mucocelelike tumor and mucinous carcinoma. STUDY DESIGN: All mucinous neoplasms diagnosed by fine needle aspiration and confirmed by histologic examination were reviewed to detect the cytologic findings helpful for the differentiation. The cytologic findings were correlated with the histologic findings. RESULTS: Cytologically, mucinous carcinomas were highly cellular and showed many single epithelial cells and variably formed epithelial cell clusters in abundant extracellular mucin. Malignant cells exhibited round, atypical nuclei; granular chromatin; and small nucleoli. Mucocele like tumor showed low cellularity with scanty, monolayered, small sheets of epithelial cells and abundant, extracellular mucin. Myoepithelial cells were present within the epithelial cell sheets. Tumor cells were usually small, with uniform, round nuclei; fine chromatin; and absence of nucleoli. CONCLUSION: Cytologic findings of mucocelelike tumor and mucinous carcinoma were different in cellularity, shape of cell clusters and nuclear features, although mucocelelike tumors having a carcinoma component were similar to mucinous carcinoma. Awareness of the cytologic findings of breast mucinous neoplasms is important to make a specific diagnosis.     

Image analysis of Feulgen-stained c-H-ras-transformed NIH/3T3 cells

Feulgen-DNA content, nuclear phenotypes, and levels of chromatin condensation were evaluated by image analysis in NIH/3T3 cells transformed with the c-H-ras oncogene of T24 cells. Three nuclear phenotypes, differing from those of untransformed control cells and defined in terms of patterns of chromatin condensation, were demonstrated microspectrophotometrically for the tumor cells. Polyploidy could only be observed in nuclei with extensive and deeply stained areas covered with condensed chromatin, i.e., only in a small fraction of the tumor cell nuclear population. The increased chromatin condensation that appeared with cell transformation affected the euchromatin zones. The image analysis provided data that, compared with those obtained in other situations involving cell transformation, could be relevant to the understanding of changes in chromatin supraorganization related to tumorigenesis and to tumor cell diagnosis.     

Evidence of repetitive patterns of chromatin distribution in cell nuclei of rat liver

Samples of rat livers were fixed in glutaraldehyde, contrasted en bloc with phosphotungstic acid, embedded in an epoxy resin and serially sectioned. The study of three-dimensional models of 20 complete nuclei shows that all of them share some general features: they have more than one nucleolus (2-4), an irregular layer of compact chromatin adjacent to the nuclear membrane and well-delimited clumps of chromatin both in the nuclear sap and surrounding the nucleoli. A space of 8 sections containing the central nucleolus and a lateral one was studied in detail. In this space, 8 clumps of compact chromatin were found in 17 nuclei and 9 clumps in the other 3 nuclei. No other number of clumps was found in those zones. In all the nuclei studied the compact chromatin surrounding the central nucleolus contacts the nuclear envelope. This contact takes place in a region almost diametrically opposed to the lateral nucleolus in 13 nuclei. In 7 nuclei, these structures were at angles between 50 and 125 degrees. These results support the existence of nonrandom repetitive patterns of chromatin distribution in liver cells.     

The cytopathologic diagnosis of esophageal adenocarcinoma

The diagnostic cytologic features were analyzed in 18 cases of histopathologically proven esophageal adenocarcinoma accessioned at the Johns Hopkins Hospital between 1975 and 1988 for which cytologic material was available. Primary esophageal adenocarcinoma was diagnosed in 15 of 18 cytologic specimens (83%); in 3 cases (17%), carcinoma was suspected, but the changes were nondiagnostic. The most consistent cytologic changes included both architectural features (loss of orientation and nuclear crowding) and criteria of malignancy (high nuclear/cytoplasmic ratios and prominent nucleoli). In the 15 diagnostic cases, the nucleoli were small in 8 and round in 11; in the majority of these cases, the nuclei contained one to three nucleoli. In addition, nuclear and cytoplasmic molding was seen in 9 of these 15 cases, hyperchromasia was present in 8, coarse chromatin clumps were seen in 5, and tissue fragments tended to be multilayered. Review of the three nondiagnostic cases showed that scant material was present in two; the third case had abundant material, but only nondiagnostic changes, suggesting a sampling error. Barrett mucosa was seen in 7 of the 18 cases. These cases show that esophageal adenocarcinoma can be reliably diagnosed on cytologic preparations, based on the consistent architectural features and the usual cellular criteria of malignancy.     

Endocervical glandular neoplasia and its mimics in ThinPrep Pap tests. A descriptive study.

OBJECTIVE: To document the cytologic features of endocervical adenocarcinoma in situ (AIS) and invasive endocervical adenocarcinoma as observed in ThinPrep slides and to compare these features with those that have been described for conventional smears. STUDY DESIGN: Six cases of endocervical AIS and three cases of invasive adenocarcinoma were evaluated with respect to 3 low-power and 14 high-power features. All cases were biopsy proven. Glandular "look-alikes" (tubal metaplasia, n = 3; florid repair, n = 3; sampling of lower uterine segment, n = 1) were also examined. RESULTS: All cases of AIS contained dark groups and sheets at screening power. At higher power, nuclear detail was extremely well visualized. All cases had crowding, continuous depth of focus, variability of nuclear size and shape within groups, irregular nuclear membranes, uniformly stippled chromatin and at least occasional single atypical cells. Only one case lacked nucleoli. Traditional features (strips, feathering, rosettes and mitoses) were observed about as frequently as in conventional smears. Invasive lesions had many of the same features, with relatively more inflammation and lysed blood. Nonneoplastic look-alikes could be distinguished from neoplasms using traditional criteria. CONCLUSION: In this small study, AIS and invasive endocervical adenocarcinoma maintained the features previously described for conventional smears. Improved visualization of nuclear detail may allow the application of additional criteria, such as irregular nuclear membranes and the more consistent presence of nucleoli, for distinguishing glandular neoplasms from their look-alikes.     

Diffusion-limited compartmentalization of mammalian cell nuclei assessed by microinjected macromolecules

In order to investigate the accessibility of the nucleoplasm for macromolecules with different physical properties, we microinjected FITC-conjugated dextrans of different sizes as well as anionic FITC-dextrans and FITC-poly-L-lysine into mammalian cell nuclei. Small dextrans displayed a homogeneous nuclear distribution. With increasing molecular mass (42 to 2500 kDa), FITC-dextrans were progressively excluded from chromatin regions, accumulating in and thereby outlining an apparently extended interchromatin space. Anionic FITC-dextrans (500 kDa) showed complete exclusion from labeled chromatin regions, while the positively charged FITC-poly-L-lysine was to some extent present within the chromatin regions. Moreover, the FITC-poly-L-lysine preferentially localized at the nuclear periphery. We also found a size-dependent exclusion of FITC-dextrans from nucleoli regions, while the FITC-poly-L-lysine accumulated in the nucleoli. Thus, the distinct and restricted nuclear accessibility for macromolecules is dependent on molecule size and electrical charge.     

A further contribution on nucleoli of human lymphocytes.

Cultured human lymphocytes were investigated by means of light as well as electron microscopic procedures to provide more information on the structural organization of their nucleoli. The transformation of ring shaped nucleoli to nucleoli with less or more distinct nucleolonemata in PHA stimulated cells was characterized by a marked increase of granular RNP components in number indicating the activation of their production. This phenomenon seems to be related not only to the activation of the ribosomal RNA synthesis but also to its processing. The appearance of fibrillar RNP components in the central area of the ring shaped nucleoli apparently represents the first sign of the nucleolar RNA synthesis in these cells. The proportion of fibrillar and granular nucleolar RNP comonents in PHA inresponsive lymphocytes was similar to that in lymphocytes from patients with the usual type of lymphocytic leukemia. The intranucleolar chromatin areas appeared to be larger in PHA stimulated lymphocytes but the proportion of these areas to the nucleolar body did not show substantial difference as compared to the resting cells.     

In situ ultrastructural localization of sugar-binding sites in lizard granulosa cell nuclei

Mannose-binding sites were detected at the ultrastructural level in nuclei of lizard granulosa cells in situ by means of mannosylated ferritin. When ultrathin sections of material embedded in glycol methacrylate were incubated with mannosylated ferritin, a strong labelling was observed over nucleoli, chromatin and the external leaflet of the nuclear envelope, but no labelling was detected in the perinuclear space except for nuclear pores. This labelling was clearly inhibited when sections were incubated in a solution containing both mannosylated ferritin and a sugar-related neoglycoprotein (mannosylated serum albumin). These ultrastructural data supporting the existence of nuclear lectin-like components in reptilian cells are in agreement with our previous findings about such components in nuclei isolated from mammalian cells. Owing to the unique organization of the granular component of the nucleoli in specialized granulosa cells, we are able to show that some of the mannose-binding sites are associated with ribosomal precursors.     

Calculus artifact. A challenge in urinary cytology.

OBJECTIVE: To retrospectively review calculus artifact and compare it with instrument artifact and papillary transitional cell carcinoma (TCC). STUDY DESIGN: Voided urine specimens from patients with calculi (65), TCC (low grade, 10, high grade, 34) and history of prior instrumentation (12) were studied. RESULTS: Nineteen specimens of calculus artifact had unremarkable cytology. Forty-six specimens had abnormal single cells or papillary clusters and cell balls or a mixture of both. The papillary groups had smooth as well as irregular borders, a cytoplasmic collar and cells with occasional cytoplasmic vacuoles, slightly increased nuclear/cytoplasmic (N/C) ratio and inconspicuous nucleoli. Squamous preponderance and birefringent crystals were seen. In instrumentation artifact, papillary clusters or three-dimensional cell balls had smooth borders, cytoplasmic collars, an occasional cytoplasmic vacuole, normal N/C ratio, regular nuclear membrane and finely granular nuclear chromatin. In TCC, papillary clusters with loss of polarity and irregular borders were present in both grades but were predominant in low grade TCC. No cytoplasmic collar was noted. In high grade TCC, single cells and nuclear alterations were more pronounced, with increased N/C ratio, hyperchromasia, coarse chromatin, irregular nuclear envelopes, prominent nucleoli and rare mitosis. CONCLUSION: Calculus artifact can produce papillary clusters masquerading as papillary TCC. Unlike instrument artifact, there may be significant nuclear atypia, which could be reversible. To avoid diagnostic pitfalls, further investigation is suggested after removal of calculus.     

Cytology of pulmonary adenocarcinomas showing enteric differentiation

OBJECTIVE: To evaluate cytologic differences between primary pulmonary adenocarcinomas showing enteric differentiation (PAED) primary pulmonary adenocarcinomas of ordinary structure (PAC) and pulmonary metastases from colorectal carcinomas (MCR). STUDY DESIGN: During an 18-year period (1986-2003), cytologic materials were obtained from 5 PAEDs confirmed by pathologic examination of surgically resected specimens at the Cancer Institute Hospital. Aspiration cytologic and/or imprint smears of routine samples stained by the Papanicolaou method from the PAED cases were reviewed in comparison with 10 cases each of PAC showing a tubular pattern and MCR. RESULTS: The aspiration biopsy cytology and imprints showed similar features. Abundant necrotic debris in the background was recognized in a majority of all cases independent of the group. None to slight overlapping of tumor cells and less frequent palisading or glandular arrangements were characteristic features of PAED, significantly differing from MCR. Moreover, differences in nuclear features were evident as follows: in the MCR group, nuclear chromatin was hyperchromatic and coarsely condensed, and there were prominent nucleoli, whereas a slightly hyperchromatic pattern with some small to enlarged nucleoli was typical of PAED and PAC cases. CONCLUSION: Although diagnosis of PAED by routine cytology is difficult due to the features of the lesion, differential diagnosis between PAED, PAC and MCR is a possible using conventional cytologic criteria.     

Intraocular lymphoma. Cytologic diagnosis and the role of immunologic markers

We retrospectively reviewed the cytology and immunohistochemistry of vitreous cells from 14 patients with benign or malignant intraocular diseases. Nine patients had intraocular lymphoma and five had benign forms of diffuse uveitis. The most useful cytologic criteria for lymphoma included an irregular nuclear outline, a coarse chromatin pattern and prominent nucleoli. In several cases, it was necessary to obtain more than one specimen to establish the diagnosis of lymphoma. When vitreous fluid was mixed with a balanced salt solution prior to processing, a resulting artifact interfered with interpretation of the specimen. A diagnosis of lymphoma was established by cytology in all nine patients; immunohistochemical techniques were less sensitive than was cytology.