The use of antibodies to intermediate filament proteins in the differential diagnosis of lymphoma versus metastatic carcinoma

Summary Forty-nine cases encompassing 16 different types of malignant lymphoma were examined for their intermediate filament protein (IFP) type by indirect immunofluorescence microscopy of cryostat sections. In all cases, vimentin was shown to be the only IFP type detectable in these tumours. Lymphomas are negative for keratin and desmin, which are characteristic for benign and malignant epithelial or muscular tissues respectively. In addition, eighteen cases are described in which antibodies to intermediate filament proteins were used successfully to distinguish between lymphoma and metastatic carcinoma where differential diagnosis was difficult or impossible on the basis of routine histology.     

Fine needle aspiration cytology of metastatic lymphoepithelioma. A case report

A case is presented of lymphoepithelioma (undifferentiated nasopharyngeal carcinoma) metastatic to the cervical lymph nodes in a 12-year-old boy for whom material was obtained by fine needle aspiration (FNA) for the primary diagnosis as well as for ancillary studies. Papanicolaou-stained smears demonstrated the characteristic cytopathologic features of Regaud-type lymphoepithelioma; the diagnosis was substantiated by immunocytochemical and electron microscopic studies. This report discusses the reliability and rapidity of FNA in definitively diagnosing undifferentiated metastatic malignancies as well as providing superior material for ancillary studies demanded by lesions with complicated and difficult differential diagnoses.     

Nasopharyngeal carcinoma and Burkitt's lymphoma in a Canadian family. I. HLA typing,EBV antibodies and serum immunoglobulins.

Two nasopharyngeal carcinomas of the lymphoepithelioma type and two Burkitt''s lymphomas with the characteristic histopathologic features developed in three siblings and one first-degree cousin in a large French-Canadian family. Epstein-Barr virus antibody titres in the two lymphoepithelioma cases but not in the Burkitt''s lymphoma cases were, as expected, greatly elevated. HLA typing of the family members failed to disclose HLA antigens A2 and B Sin-2, which have been associated with lymphoepithelioma in Asia. The occurrence, however, of a plasmacytoma in one other first-degree cousin and low serum IgA values in several siblings and cousins suggests the possibility of a genetically determined predisposing B-cell dysfunction in the development of these tumours.     

Immunohistochemical demonstration of keratins in human ovarian neoplasms. A comparison of methods

A comparison of five immunohistochemical methods for the demonstration of keratins in human ovarian neoplasms using affinity-purified polyclonal rabbit antibody was made. The use of indirect immunofluorescence on frozen sections briefly fixed in acetone was found to be the most sensitive method and demonstrated keratin in all 14 primary and 1 metastatic ovarian epithelial neoplasms studied. Protein A-peroxidase, peroxidase--antiperoxidase (PAP), indirect peroxidase, or the avidin--biotinylated peroxidase complex (ABC) methods applied to formalin-fixed tissues were less sensitive and led to false negative results in 9 of 15, 1 of 15, 8 of 15, and 6 of 15 cases, respectively. A single case of dysgerminoma failed to reveal keratin by any method.     

Immunohistochemical differentiation of malignant mesothelioma, mesothelial hyperplasia and metastatic adenocarcinoma in serous effusions, utilizing staining for carcinoembryonic antigen, keratin and vimentin

The cytologic diagnosis of malignant mesothelioma and its distinction from mesothelial hyperplasia and metastatic adenocarcinoma is consistently difficult; tissue studies utilizing the immunohistochemical profiles of carcinoembryonic antigen (CEA) and keratin have demonstrated a reproducible distinction between these tumors. Mesothelium contains vimentin in addition to keratin, but its characterization is hindered by its poor preservation in formalin fixatives; alcohol fixation is far superior. Alcohol-fixed, Papanicolaou-stained smears of serous fluids from five cases of reactive mesothelium, five metastatic adenocarcinomas and five malignant mesotheliomas were stained with polyclonal CEA, antikeratin monoclonals AE1 and AE3 (combined) and monoclonal vimentin utilizing the peroxidase-antiperoxidase method. The study revealed the excellent preservation of mesothelial vimentin staining in all three groups. The reactive mesothelium and mesothelioma groups were strongly positive for vimentin and keratin whereas the metastatic adenocarcinoma group was only positive for keratin and CEA (except one case). These findings support the results of previous tissue studies, disclosing CEA staining in the metastatic adenocarcinomas, but not in the mesotheliomas, and the inability of keratin staining to distinguish between the two. The findings also emphasize that positive vimentin staining will usually exclude a metastatic adenocarcinoma, but will not distinguish between neoplastic and reactive mesothelial states.     

Fine needle aspiration cytology of Hodgkin's lymphoma: A cytohistologic correlation study from a cancer center in Kuwait

OBJECTIVE: To assess the diagnostic accuracy offine needle aspiration cytology (FNAC) in the diagnosis of Hodgkin's lymphoma (HL). STUDY DESIGN: We selected all the cases in which a cytologic diagnosis of HL, suggestive of or suspicious for HL, or HL as the prime differential diagnosis was offered on FNAC. These cases were correlated with histopathologic follow-up. Cases of primary HL diagnosed on cytology but without histopathology were excluded from the study. RESULTS: Histopathologic follow-up was available in 46 cases. Of these, 42 were correctly diagnosed as HL, and there was a discorrelation in 4 cases, comprising 3 cases of non-HL (T-cell-rich B-cell lymphoma [TCRBCL]-2, anaplastic large cell lymphoma-1) and 1 case of metastatic carcinoma. Overall accuracy was 91.3%. In 14 cases, the cytologic features were diagnostic ofrecurrence; hence, no histopathologic examination was done. No follow-up was available for the remaining 19 cases, which were excluded from the study. CONCLUSION: FNAC is very useful for rapid and accurate approach to the diagnosis of recurrent and most cases of primary HL. Because of morphologic similarities, it is difficult to differentiate HL from anaplastic large cell lymphoma and TCRBCL on FNAC. It is advisable to request a histopathologic examination in all cases of primary HL.     

Diagnosis of metastatic renal cell and thyroid carcinomas by intermediate filament typing and cytology of tumor cells in fine needle aspirates

Coexpression of keratin and vimentin was found in carcinoma cells of 13 fine needle aspirates of metastatic lesions that showed some cytologic features considered to be consistent with a renal or thyroid origin, but in which a large number of other possible primary sites would have to be taken into account on the basis of the morphologic evidence alone. Immunochemistry thus narrowed the cytologic differential diagnosis to thyroid, renal, endometrial and ovarian carcinomas, which are known to show true coexpression of keratin and vimentin. In most cases, clinical data available at the time of the fine needle aspiration supported the thyroid or renal origin of the carcinoma cells found in the aspirates. In two cases, which lacked significant clinical information, the diagnosis of metastatic renal cell carcinoma was provided on the basis of the combined morphologic and immunocytochemical evidence. In these two cases, computed tomography or ultrasonography revealed kidney tumors, which were removed and confirmed histologically to be clear cell carcinomas.     

Fine needle aspiration cytology of neoplasms metastatic to the breast

The fine needle aspiration (FNA) cytologic findings in 18 cases of metastatic neoplasms of the breast are reported. The cases were encountered in a combined series of 2,529 FNA breast biopsies, of which 666 were malignant; the metastatic neoplasms of the breast thus constituted 2.7% of all the malignant breast tumors. The series consists of 15 women and 3 men, with a mean age of 48 years (range of 11 to 73 years). Sixteen biopsies confirmed metastatic malignancy in patients with known extramammary primaries; the prebiopsy clinical diagnoses in six of the patients were benign breast lesions. In eight patients, the clinical differential diagnosis was either a benign or malignant primary breast lesion versus a metastatic malignancy. In two additional patients, the FNA biopsy identified metastatic neoplasms from unsuspected extramammary primaries. The metastatic neoplasms included three small-cell carcinomas of the lung, one squamous-cell carcinoma of the lung, two malignant melanomas, three ovarian malignancies, including a dysgerminoma, and one each of carcinoma of the fallopian tube, endometrial carcinoma, transitional-cell carcinoma of the urinary bladder, prostatic carcinoma, acute granulocytic leukemia, lymphoma, mycosis fungoides, hepatoma and neuroblastoma of the retroperitoneum. Recognition of unusual cytologic patterns raised the suspicion of, or confirmed the diagnosis of, malignancy in all cases, with no false-negative diagnoses. None of the cases were cytologically interpreted as a primary breast malignancy. Ancillary studies performed on the FNA material, including immunocytochemistry, contributed to a definitive diagnosis in three cases. FNA diagnosis of metastatic malignancy of the breast is essential in order to avoid unnecessary mastectomy and to ensure appropriate chemotherapy and/or irradiation treatment.     

Functional analysis of mouse keratin 8 in polyoma middle T-induced mammary gland tumours

Keratin 8 and 18 are commonly used as tumorigenic markers for various types of carcinomas. They are known to be involved in cell migration, cell invasiveness, plasminogen activity and drug and radiation resistance. To ascertain a potential function for simple epithelium keratins in mammary adenocarcinoma in vivo, keratin-8-deficient mice (mK8) were mated with transgenic mice carrying the middle T oncogene driven by the MMTV promoter. The resulting mK8 knockout and control progeny carrying the middle T transgene developed mammary gland tumours with the same incidence. However, the onset of palpable mammary gland tumours occurred earlier in mK8 mutant than in control mice. This effect was prominent in males where the onset in control animals is delayed overall, because of the lower hormonal inducibility of the MMTV promoter. Metastatic foci were observed in the lungs of all females and of a few males, idependently of the genotype. Histological analysis revealed no morphological differences of the tumorigenic cells in primary tumours nor in metastatic foci. As expected, keratin 8 was absent in the mK8 tumours. Keratin 7 (mK7), keratin 18 (mK18) and keratin 19 (mK19) protein were observed in both primary and metastatic foci. These results constitute the first in vivo analysis of the role of simple epithelium keratins in mammary carcinogenesis. It demonstrates that the latency, but not the incidence nor the morphological features, of PyV middle T-induced mammary gland tumours is affected by keratin 8 deficiency     

The use of a panel of monoclonal antibodies in the evaluation of cytologic specimens from the central nervous system

A panel of monoclonal antibodies was tested immunohistochemically to determine the utility of such reagents in distinguishing among metastatic carcinoma, lymphoma, leukemia and primary brain tumors. The monoclonal antibodies used were: (1) a cocktail comprised of three anti-glial fibrillary acidic protein antibodies (alpha-GFAP); (2) UJ13A, a panneuroectodermal antibody; (3) B72.3, which recognizes a carcinoma-distinctive tumor-associated glycoprotein complex; and (4) 2D1, a pan-leukocyte antibody. Fifty-three specimens (21 cerebrospinal fluids, 1 ventricular fluid, 2 brain cyst fluids, 12 needle washings, 15 imprints, 1 subdural fluid and 1 post-shunt fluid) were obtained from 21 gliomas, 2 meningiomas, 1 pineoblastoma, 11 metastatic tumors, 3 lymphomas, 1 leukemia and 14 cases without tumor. alpha-GFAP stained all 21 gliomas and 5 of 5 cases containing reactive brain fragments. UJ13A had a reactivity pattern similar to that of alpha-GFAP, but also stained the meningiomas, pineoblastoma, oat-cell carcinoma and embryonal rhabdomyosarcoma. B72.3 stained all adenocarcinomas and the large-cell carcinoma. 2D1 stained lymphoma and leukemia, all inflammatory cells and 4 of 12 glioblastomas. Although no single antibody was diagnostic of a specific tumor type, this panel accurately differentiated among most primary brain tumors, metastases, leukemias and lymphomas.     

Keratin 20 - a diagnostic and prognostic marker in colorectal cancer?

Colorectal cancer cells characteristically show strong expression of keratin 20 (K20) and lack expression of keratin 7 (K7). The biological significance of reduced K20 expression, however, is unclear. 381 colorectal cancers with 148 corresponding metastases were evaluated for K20 and K7 expression by immunohistochemistry using a tissue microarray technique. K20 immunoreactivity was assessed semiquantitatively as either negative, low (<50% of cancer cells) or high (≥50% of cancer cells). Progression-free and cancer-specific survivals were determined using the Kaplan-Meier method. Expression of K20 was observed in 348 out of 372 (94%) evaluable primary tumors, with 135 (36%) cases showing low K20 and 213 (57%) cases high K20 expression, while 24 (6%) tumors completely lacked K20 immunoreactivity. Reduced K20 expression (lack of staining or low expression) was significantly associated with poor differentiation, large tumor size and mismatch repair deficiency, but did not significantly affect patients' outcome. Immunoreactivity of K20 and K7 in metastatic tissues matched well with that of corresponding primary tumors, with high concordance for lymph node (p<0.001) and distant metastases (p<0.001), respectively. In conclusion, our data illustrate the value of keratin subtyping in carcinoma of unknown primary (CUP) syndrome: K20 expression is common in colorectal cancer and the K20 high / K7 negative immunoprofile represents the predominant phenotype. Reduced K20 expression may, however, lead to false-negative assessment of metastatic deposits if only small amounts of tissue are obtained (e.g. in needle biopsies), particularly in poorly differentiated cancers. Reduced expression of K20 may be used to select tumors for microsatellite instability testing.     

Malignant melanoma in fine needle aspirates and effusions. An immunocytochemical study using monoclonal antibodies

The value of monoclonal antibodies (MAbs) for the immunodetection of keratin, vimentin and two melanoma-associated antigens recognized by NKI/C3 and NKI/Bteb for the diagnosis of malignant melanoma has been previously established on histologic preparations. In the present study, cytologic preparations from 20 fine needle aspirates and effusions from patients with malignant melanoma were evaluated using these antibodies. Twenty of 20 smears were negative for keratin, and 20 of 20 smears were positive for vimentin. Positivity for NKI/C3 was seen in 12 of 12 cases studied, and for NKI/Bteb in 12 of 13 cases. These results indicate that a panel of MAbs consisting of anti-keratin, anti-vimentin, NKI/C3 and NKI/Bteb is useful for a more accurate diagnosis of malignant melanomas on cytologic preparations. The expression of these antigens in melanoma cells in cytologic smears can be a valuable aid in the detection of primary (noncutaneous) and metastatic melanomas by fine needle aspiration.     

Lymphoepithelioma – a tumour rarely observed in children (3 cases)

Lymphoepithelioma rarely develops in children. In its early stage it may manifest itself only as enlarged cervical lymph nodes, which is likely to cause difficulties in the initial diagnosis. Radiotherapy is the treatment of choice, however, chemotherapy has also been used. The paper describes three cases of children treated for lymphoepithelioma at the Department of Children Hematology and Oncology in Lublin between 1991 – 2001. In all cases, the diagnosis was based on histopathological examinations of the tumour or lymph node biopsies. The methods of treatment used were different in each case and the longest disease free survival was 3 years. Therefore it seems necessary to design a uniform protocol of treatment for children with lymphoepithelioma.The first child was treated only to radiotherapy. This choice was based on lack of results of well conducted trials of cytostatic treatment. The good result of our treatment confirmed the data presented by other with the use of radiotherapy alone.In the second case, in case of large tumour, paralysis of cranial nerves, this patient was refered to combined treatment (radio-chemotherapy). In this case the partial remission was achived.In the third case, chemotherapy (cisplatin + 5-fluorouracil) resulted in perfect remission of the primary tumour and metastases to the lymph nodes while radiotherapy allow to achive complete control of the primary tumour and metastases to lymph nodes.     

Nucleolar organizer regions in aspirates of malignant lymphomas and benign disorders of the lymph nodes.

Silver staining of nucleolar organizer regions (AgNOR) was used to differentiate malignant lymphoma and chronic lymphadenitis. Aspiration smear samples from lymph nodes of 120 cases, including 43 non-Hodgkin's lymphoma, 3 Hodgkin's disease, 56 chronic lymphadenitis, 7 tuberculosis, 6 reactive hyperplasia and 5 samples from other diseases (epidermoid cyst, branchial cyst, mixed tumor, lymphoepithelioma and nodulous disease), were investigated. The number of AgNORs in 200 cells in each sample was counted, and the mean +/- SD in each disease was calculated: non-Hodgkin's lymphoma, 6.58 +/- 2.37; Hodgkin's disease, 4.22 +/- 0.5; chronic lymphadenitis, 1.16 +/- 0.1; tuberculosis, 1.13 +/- 0.14; reactive hyperplasia, 1.48 +/- 0.25; other diseases, 1.47 +/- 0.31. The results indicate that the AgNOR count in malignant lymphoma differed highly significantly from that in benign disease (P less than .001). The size of AgNORs in malignant lymphoma and chronic lymphadenitis was measured, and the maximum diameter and area of lymphocyte and lymphoma cell were: lymphocyte, 0.93 +/- 0.12 microns, 0.61 +/- 0.13 microns 2; lymphoma cell, 0.83 +/- 0.22 microns, 0.50 +/- 0.25 microns 2. The AgNOR sizes in malignant lymphoma were significantly smaller than in chronic lymphadenitis (P less than .001).     

Cytomorphology of Metastatic Melanoma—Use of S-100 Protein In the Diagnosis of Amelanotic Melanoma

The cytomorphological features of cells from 52 cases of metastatic melanoma obtained by fine needle aspiration cytodiagnosis were studied. Morphologically, 11, 19 and 22 cases were classified as spindle, epithelial, and mixed cell types of metastatic melanoma respectively. There were 34 melanotic and 18 amelanotic melanomas. Besides melanin, the presence of intranuclear cytoplasmic inclusions, eosinophilic macronucleoli and giant cells were helpful in the diagnosis of a melanoma. Where attempted, staining for S-100 protein was positive in all the 19 cases (eight amelanotic and 11 sparsely pigmented melanomas). In addition eight cases of metastatic tumour where a differential diagnosis of poorly differentiated carcinoma or large cell lymphoma was entertained, were also studied for localization of S-100 protein and all were found to be negative. Electron microscopy was performed in five cases and showed the presence of melanosomes and/or premelanosomes.     

The role of fine needle aspiration cytology (FNAC) in the investigation of superficial lymphadenopathy; uses and limitations of the technique

Aspirates (n = 163) from 157 patients with enlarged superficial lymph nodes were obtained over a 5-year period in a combined surgical/FNAC clinic. A definitive diagnosis was achieved in over 77% of the cases: benign 52.7%, malignant 25.1%. The diagnostic accuracy was 94.4%, sensitivity 85.4%, and specificity 100%. The false-negative rate was 12.5% but decreased to 3.5% when lymphoma cases were excluded. There were 36 cases of metastatic disease, the majority of which were from a primary breast carcinoma. The main diagnostic difficulty was in distinguishing low-grade lymphoma from reactive hyperplasia. An added advantage was that aspirated material could be used in ancillary tests to help with the differential diagnosis. FNAC has a well-defined role in the investigation of superficial lymphadenopathy. Used in the proper setting it will provide a definitive diagnosis in the majority of cases, especially relating to recurrent malignancy or metastatic disease. Patients with a reactive cytological picture and no clinically suspicious symptoms could be spared unnecessary surgery and reviewed through follow up. This technique is cost-effective, of high diagnostic accuracy, and results in considerable resource savings.     

Fine needle aspiration cytology of primary lymphoma of the thyroid: a report of 17 cases.

Between 1980 and 1998, 4272 thyroid surgical specimens with a preoperative fine needle aspirate were sent to our Anatomical Pathology Department. Among these cases there were 17 primary thyroid lymphomas, which constituted 0.3% of all the thyroid lesions and 2.3% of the thyroid malignancies. Seven cases were diffuse large B-cell (DLBC) lymphomas and 10 were MALT lymphomas. Of the DLBC lymphomas six were correctly diagnosed by fine needle aspiration cytology (FNAC) and one was diagnosed as positive for malignancy, and among MALT lymphomas four were diagnosed as lymphoma, four as suspicious for lymphoma, and three as Hashimoto's thyroiditis (HT). Our data indicate that the diagnosis of primary thyroid lymphoma of high grade is easy, and immunocytochemistry (ICC) can confirm suspicious cases. The diagnosis of MALT lymphoma is more difficult; ICC can confirm suspicious cases, and false-negative results seem to be caused by sampling error, because HT usually coexists with MALT lymphoma.     

Histopathological and immunological studies of nasopharyngeal carcinoma.

From 1968 to 1973, 793 cases of nasopharyngeal malignancies in Japan were examined histopathologically and immunologically. The majority of the carcinomas were undifferentiated squamous cell carcinomas, including transitional cell carcinoma and lymphoepithelioma. These findings correspond well with those of other countries. There were more well differentiated carcinomas in the old than in the young age groups. The positive rate (80%) and the geometric mean of the anti-VCA-antibody titers (more than 1:750) were remarkably high in the lymphoepithelioma group. These two factors seem to be very important to the study of oncogenesis of nasopharyngeal carcinoma (NPC). The relationship between subpopulations of peripheral lymphocytes in NPC and histopathological classification was investigated. The lymphoepithelioma group had a higher proportion of B cells (complement receptor cells) to T cells (erythrocyte rosette forming cells) than healthy persons throughout the clinical course, and its prognosis was not good.     

Extrauterine malignancies. Role of Pap smears in diagnosis and management.

OBJECTIVE: To further elucidate the cytologic manifestations of extrauterine malignancies, to evaluate their possible distinction from primary cervical malignancies and to analyze their clinical significance and role in staging. STUDY DESIGN: Papanicolaou (Pap) smears in 33 cases with abnormal cells originating in histologically proven extrauterine carcinomas were evaluated. These cases came from the files of the Medical College of Pennsylvania and Lankenau Hospitals. RESULTS: Ovary, gastrointestinal tract and breast were the three most frequent primary sites, accounting for 28 of the 33 cases (85%). The histologic types encountered were adenocarcinoma, 29 cases (88%); mucoepidermoid carcinoma, 1 (3%); small cell carcinoma, 1 (3%); cloacogenic carcinoma and large cell lymphoma, 1 (3%). The following diagnoses were rendered at the time of initial evaluation: adenocarcinoma consistent with metastasis, 21 cases; carcinoma, primary versus metastatic, 2; adenocarcinoma, suspicious for endometrial primary, 2; suspicious for carcinoma, 1; and atypical glandular cells, 7. CONCLUSION: The yield for positive Pap smear diagnoses in extrauterine malignancies is best in patients with an established diagnosis of a primary neoplasm. The degree of tumor differentiation and extent of tumor involvement did not appear to correlate with diagnostic yield. There appeared to be no statistically significant association of tumor diathesis with primary versus metastatic carcinoma and presence or absence of documented local involvement of the endometrium, cervix or vagina. Therefore, while Pap smears can serve as a diagnostic tool in the evaluation of extrauterine malignancies, they are best utilized as an adjunct to tumor staging and patient management.     

Reliability and limitations of fine needle aspiration cytology of lymphadenopathies. An analysis of 1,261 cases

In a study spanning over two years, 1,261 cases with clinically significant lymphadenopathies were subjected to fine needle aspiration cytology (FNAC) to evaluate the reliability and limitations of the procedure. In the first phase of the study, consisting of 100 cases, the cytologic diagnosis was compared with histopathology, and the results were analyzed with a view to standardizing the procedure. In the second phase of the study, consisting of 1,161 patients, FNAC was used as the primary modality of diagnosis. Excision biopsy was done only when there was a clinical-cytologic discrepancy, failure to respond to treatment or FNAC diagnosis of non-Hodgkin's lymphoma. The highest diagnostic accuracy with FNAC was observed in metastatic carcinoma. Though tuberculous lymphadenitis, reactive hyperplasia and lymphoma were diagnosed with almost similar accuracy, reactive hyperplasia and non-Hodgkin's lymphoma proved difficult to diagnose. Although FNAC has proven to be a simple, safe, reliable and cost-effective diagnostic tool for lymphadenopathies, the limitations of the procedure should be kept in mind and excision biopsy used whenever required.