Warthin's tumor: an immunohistochemical study of its lymphoid stroma

Pathogenesis of Warthin's Tumor: Neoplastic or Non-Neoplastic?

Warthin's tumor is the second most frequent neoplasm next to pleomorphic adenoma in the salivary gland, mostly in the parotid gland. The epithelial cells constituting a tumor are characterized by the presence of mitochondria that undergo structural and functional changes, resulting in the development of oncocytes. In addition to containing epithelial cells, Warthin's tumors contain abundant lymphocytes with lymph follicles (germinal centers) that are surrounded by epithelial cells. The pathogenesis of Warthin's tumor is not fully understood, and several hypotheses have been proposed. The risk factors for the development of Warthin's tumor, which predominantly occurs in males, include aging, smoking, and radiation exposure. Recently, it has been reported that chronic inflammation and aging cells promote the growth of Warthin's tumor. Several reports regarding the origin of the tumor have suggested that (1) Warthin's tumor is an IgG4-related disease, (2) epithelial cells that compose Warthin's tumor accumulate mitochondria, and (3) Warthin's tumor is a metaplastic lesion in the lymph nodes. It is possible that the pathogenesis of Warthin's tumor includes mitochondrial metabolic abnormalities, accumulation of aged cells, chronic inflammation, and senescence-associated secretory phenotype (SASP). In this short review, we propose that DNA damage, metabolic dysfunction of mitochondria, senescent cells, SASP, human papillomavirus, and IgG4 may be involved in the development of Warthin's tumor.

Lymphocyte recruitment via high endothelial venules in lymphoid stroma of Warthin's tumour

AIMS

Warthin's tumour is composed of bilayered oncocytic epithelium and organised lymphoid stroma, which resembles mucosa-associated lymphoid tissue (MALT); however, the histogenesis of the lymphoid stroma is not fully understood. We hypothesised that lymphocytes consisting of the stroma are recruited via high endothelial venules (HEVs) by the mechanism operating in normal lymphocyte homing in secondary lymphoid organs. The aim of this study was to determine immunohistochemically the molecules expressed on these HEVs.

METHODS

Tissue sections of Warthin's tumour (n = 10) were immunostained for vascular addressin-related antigens including peripheral lymph node addressin (PNAd) and mucosal addressin cell adhesion molecule 1 (MAdCAM-1). An L-selectin·IgM chimera in situ binding assay was also carried out. Triple immunostaining for PNAd, CD3, and CD20/CD79α was performed to determine which lymphocyte subsets are closely associated with these HEVs.

RESULTS

HEVs in the lymphoid stroma of Warthin's tumour express PNAd, which is detected by MECA-79 as well as recently developed monoclonal antibodies S1 and S2. These HEVs were bound by L-selectin·IgM chimeras in a calcium-dependent manner, and numbers of lymphocytes, particularly T cells, attached to these HEVs.

CONCLUSIONS

The lymphoid stroma of Warthin's tumour is most likely developed by lymphocytes recruited via HEVs.

[Lymphadenoma of the parotid gland without sebaceous differentiation. Immunohistochemical investigations]

An encapsulated tumor measuring 8 cm was removed from the parotid gland in a 42-year-old man. The tumor had grown for about 5 years. The histopathological and immunohistochemical evaluation revealed a lymphadenoma without sebaceous differentiation of the epithelial component. The tumor consisted of exclusively solid epithelial islands and a lymphoid stroma with rare lymph follicles and abundant predominantly IgG plasma cells. The histogenesis of lymphadenomas is discussed in consideration of the differential diagnosis from Warthin's tumor and the data in the literature.

Molecular characterization of Warthin tumor

OBJECTIVE

Warthin tumor of the salivary gland is composed of oncocytic epithelium with a prominent follicular lymphoid infiltrate. The purpose of this study was to characterize the clonality of this lymphoid component by means of polymerase chain reaction technology.

STUDY DESIGN

DNA was isolated from paraffin-embedded tissue from 20 cases of typical Warthin tumor of the salivary gland and amplified by polymerase chain reaction to assess B- and T-cell clonality.

RESULTS

No dominant clonal populations were identified in any tumor. However, minor clonal expansions of both B and T cells were detected in up to 50% of tumors (immunoglobulin H, 50%; T-cell antigen receptor beta, 10%; T-cell antigen receptor gamma, 5%). No tumors showed evidence of bcl-2 proto-oncogene translocation, whereas 95% contained detectable Epstein-Barr virus DNA.

CONCLUSION

The B- and T-cell components of Warthin tumor are polyclonal with oligoclonal expansion of both T and B cells in some lesions.

Unilateral multiple adenolymphomas originating in the parotid gland: a clinicopathological study

The validity of Seifert's hypothesis about growth pattern of adenolymphomas has been evaluated in three of five patients with adenolymphomas of the parotid gland, who at the time of a parotidectomy, were found to have multiple unilateral adenolymphomas in the intraglandular lymph nodes. This evaluation, which was based on assessing the epithelial: lymphoid tissue ratio in excised adenolymphomas and the growth in tumor size, showed that there was no association between the histological changes in the epithelial:lymphoid tissue and the tumor size. Adenolymphomas seem to have no consistent growth pattern and develop independently. However, as multiple tumors were detected histopathologically in lymph nodes as small as 5 mm in diameter the importance of a detailed examination of patients with adenolymphomas is stressed, so that other tumours are not overlooked.

Extraparotid Warthin's Tumor: Clinical Manifestations, Challenges, and Controversies

Extraparotid Warthin's tumors continue to challenge the head and neck surgeon's diagnostic and therapeutic skills. A series of six extraparotid Warthin's tumors are presented to illustrate the need to keep a high index of suspicion for this lesion in the workup of cystic masses involving cervical levels II and III or in the event of a concomitant neck mass and a parotid Warthin's tumor. Discussion of the debate surrounding the embryogenesis and histogenesis of extraparotid Warthin's tumors follows. Clinical guidelines are suggested for the diagnosis, treatment, and follow-up of patients with extraparotid Warthin's tumors.

Characterization of lymphocyte subpopulations in Warthin's tumor

Cell suspensions from six Warthin's tumors (WTs) were characterized with fluorescence-labeled cell cytometry. WT lymphocyte subsets were identified with monoclonal antibodies directed against lymphocyte-associated cell antigens including T lymphocyte subsets, B lymphocytes, and natural killer (NK) cells. Results showed that T cell proportions were 58% and B cell proportions were 39%. The T cell helper:cytotoxic-suppressor ratio was 5.7:1 and the B to T cell ratio was 0.8:1. NK cells represented 1.3% of cells. When compared to peripheral blood lymphocytes (PBLs) in the same patients, statistically significant differences were noted between PBLs and WT lymphocytes in the percentage of B lymphocytes (P < .01), T cytotoxic-suppressor lymphocytes (P < .02), NK cells (P < .01), and in the ratios of B to T lymphocytes (P < .01) and T helper to T cytotoxic-suppressor lymphocytes (P < .03). Comparing these data to retrospective data on lymphocyte distribution in normal and reactive lymph nodes, the epithelial component does not appear to exert a local effect on the lymphoid component of WT.

Morphometrical analysis of cystadenolymphoma (Warthin's tumor). Subclassification and characterization of the lymphoid stroma in comparison with gastric lymphoid follicles

Morphometrical analysis was applied to cystadenolymphoma (Warthin's tumor, adenolymphoma: CAL). By quantitative analysis of tissue sections, the examined cases were divided into three subtypes according to the ratio of the lymphoid stroma (LS) to the whole tissue: type I "stroma-rich type", the LS of this type was more than 57% of the whole tissue; type II "typical type", the LS of this type was 37% to 56% of the whole tissue; and type III "stroma-poor type", the LS of this type was less than 36% of the whole tissue. The average age of the patients in subtypes I, II and III was 57.7, 68.0, and 62.4 years, respectively. The age of the patients with type I CAL was significantly lower than that of those with type II CAL. In many type II cases, a reticular distribution of IgE in the germinal centers was frequently observed. From an analysis of the sections immunohistochemically stained with monoclonal antibodies to B and T cells, there appeared to be a trend that the greater the percentage of the LS to the whole tissue, the lower the ratio of B cell region to the LS. In contrast to CAL, an analysis of the change of the ratio of B cell region to the lymphoid follicles (LF) seen in the gastric mucosa of patients with chronic gastritis showed that the larger the volume of LF, the higher the ratio of the B cell region to the entire LF.(ABSTRACT TRUNCATED AT 250 WORDS)

Tumor-associated lymphoid proliferation in the parotid gland. A potential diagnostic pitfall

A substantial proportion of neoplastic and nonneoplastic parotid diseases have a prominent lymphoid component. The lymphoid element in lesions such as papillary cystadenoma lymphomatosum, sebaceous lymphadenoma, and lymphoepithelial carcinoma are readily recognized as a required diagnostic element. However, when other types of benign and malignant salivary gland neoplasms demonstrate tumor-associated lymphoid proliferation, the tumor may be either misclassified or misinterpreted as metastatic disease. Examples of primary benign and malignant parotid neoplasms exhibiting tumor-associated lymphoid proliferation are documented and illustrated. Other parotid lesions that may have a lymphoid element include sialadenitis, cysts with associated lymphoid tissue, parenchymal neoplasms with an expected lymphoid component or those that arise within an intraparotid lymph node, autoimmune disease, malignant lymphoma, and metastatic disease. An approach to recognition and separation of these entities is discussed.

Extraparotid Warthin's tumours--report of 10 cases

In the period 1970-1990, 10 cases of extraparotid Warthin's tumours were registered at the Free University Hospital in Amsterdam, The Netherlands. In view of the relatively rare occurrence of these lesions, the clinical data of the patients are reported, together with a discussion on the somewhat controversial subject of extraparotid Warthin's tumours.

Immunohistochemical study of lymphoid tissue in human fetal salivary gland

Immunoreactivity of lysozyme (LY), lactoferrin (LF), alpha 1-antichymotrypsin (alpha 1-ACT), alpha 1-antitrypsin (alpha 1-AT), keratin proteins KL1, PKK1, K8.12, S-100 protein, MAM-3, MAM-6, and epithelial membrane antigen (EMA) were evaluated in lymphoid and glandular tissues of developing salivary gland of human fetus (gestational age ranging from 17 to 40 wk to investigate the role of lymphoid tissue in developing salivary glands. In a total of 79 cases, lymphoid cell aggregations were noted in parotid (57 cases), submandibular (21 cases) and sublingual (5 cases) glands. Mononuclear cells showing intense activity of LY, alpha 1-ACT and alpha 1-AT were present in the lymphoid aggregation. The glandular ducts embedded in lymphoid tissue were negative to MAM-3, MAM-6, EMA and S-100 protein, but showed positive PKK1 and KL1 reaction during early stages of development, and showed degeneration and effacement upon increase in number and LY activity of the mononuclear cells. The lymphoid aggregations progressively emerged as lymph nodes.

Oncocytic metaplasia of the nasopharynx or extra-parotid Warthin's tumour?

A case of oncocytic metaplasia obstructing the Eustachian tube in an elderly patient is described. Histologically, it was similar to Warthin's tumour of the parotid gland. The lymphocytes were predominantly T cell, unlike those of Warthin's tumour which are predominantly B cell. It is proposed that oncocytic metaplasia represents an early stage in the evolution of Warthin's tumour.

Expression of major histocompatibility complex class II antigens and interleukin-1 by epithelial cells of Warthin's tumor

The immunoreactivity for class II antigens of the major histocompatibility complex and interleukin-1 (IL-1) in Warthin's tumor (WT) cells was studied. In addition to macrophages, dendritic cells, and capillary endothelia, the luminal tumor cells and some keratinocytes in the metaplastic squamous foci exhibited immunoreactivity for both class II antigens and IL-1. The distribution of the class II antigens in the luminal tumor cells was limited to their basolateral membrane. These data, together with previous findings, strongly suggest that the luminal tumor cells of WT introduce the luminal antigen to the underlying lymphoid tissue and, thus, act as an antigen-presenting cell.

Warthin's tumor

Warthin's tumor, classed as a monomorphic adenoma, ranks second to pleomorphic adenoma in the incidence of benign neoplasms of the parotid gland. By embryologic and clinicopathologic definitions, it is a neoplasm of the parotid gland and its environs, including parotid lymph nodes. Histopathologic diagnosis requires an oncocytic (mitochondria-rich) epithelium and lymphoid stroma. Malignant Warthin's tumors are rare and are carcinomas arising from the ductal component, or non-Hodgkin's lymphomas arising from the lymphoid tissue.

Follicular non Hodgkin's lymphoma in adenolymphoma: report of a case

A case of centroblastic centrocytic follicular lymphoma arising within a bilateral adenolymphoma of the parotid glands with involvement of the adjacent lymph nodes is reported. The patient was treated with combination chemotherapy and three years after the first cycle of therapy there was no evidence of disease. The occurrence of primary malignant lymphomas in the lymphoid stroma of an adenolymphoma has seldom been discussed in literature. All cases reported of follicular centre cell type were characterized by an indolent clinical course.

Oncocytic adenocarcinoma arising in Warthin's tumor

Warthin's tumor (adenolymphoma) is a monomorphous adenoma of the salivary glands well characterized histologically. Its clinical evolution is almost invariably benign, the malignant change being extremely unusual. We present the case of a 67 year-old man with a right retromandibular tumor which has evolved over a two year period, with peripheral involvement of V, VI and VII cranial nerves on the same side, and direct invasion of intracranial structures. The biopsy revealed a classic adenolymphoma which shows foci of well differentiated adenocarcinoma. Transitional areas between benign and malignant epithelium were evident. In addition, histological findings support the hypothesis of the origin of adenolymphoma from epithelial ducts trapped in the regional lymphatic tissue.

Synchronous extra-parotid Warthin's tumour

Warthin's tumour (also known as adenolymphoma or papillary cystadenoma lymphomatosum) is benign and accounts for 12 per cent of all neoplasms of the parotid gland. A case of extra-parotid Warthin's tumour occurring synchronously in a peri-parotid lymph node is described. This is not a metastatic phenomenon and occurs as a result of salivary gland inclusions of local lymph nodes during the embryological development of the parotid. Extra-parotid Warthin's tumour should be regarded as a benign incidental finding and the prognosis is excellent.

Nasopharyngeal Warthin's tumour: a metaplastic lesion

Warthin's tumour arising from minor salivary glands of the nasopharynx is described in a patient with eosinophilic rhinitis and nasal polyposis. The microscopical features of this lesion were indistinguishable from those of Warthin's tumours of the parotid gland. The present case supports the histogenetic theory that the epithelial component of extraparotid Warthin's tumours represents reactive oncocytic metaplasia and hyperplasia induced by chronic inflammation rather than genuine neoplasia. It is suggested that the term Warthin's tumour is preferable to designations indicating neoplasia of these extraparotid lesions which are indistinguishable histologically and ultrastructurally from parotid and juxtaparotid adenolymphomas.

Difference of immunohistochemical reactions in epithelial cells of adenolymphoma

An immunoperoxidase staining technique was used for detecting alpha one-antichymotrypsin (alpha 1-ACT), alpha one-antitrypsin (alpha 1-AT), lactoferrin and transferrin in routine histological paraffin sections of 30 adenolymphomas, as well as in normal salivary gland tissue. Microscopically, the epithelial, component of adenolymphomas consisted of tall columnar luminal cells and irregularly shaped basal cells. alpha 1-ACT was detected in the luminal layer of epithelium in 27 (90%) of 30 adenolymphomas, while the basal layer was positive in 4 cases (13%). Lactoferrin could be observed in the columnar cells of 21 cases (70%) and was positive in the basal cells of 2 cases (7%). In normal salivary gland tissue, alpha 1-ACT and lactoferrin were observed in the intercalated duct and serous acinar cells. The staining pattern of alpha 1-AT in adenolymphoma was similar to those of alpha 1-ACT and lactoferrin, however, the number of positive cases for alpha 1-AT was fewer than in the alpha 1-ACT and lactoferrin. alpha 1-AT was not found in the normal salivary gland. On the contrary, the localization of transferrin in the epithelial component of adenolymphomas was exclusively different from those of alpha 1-ACT, alpha 1-AT and lactoferrin. Transferrin was found more often in the basal cells than in the tall columnar apical cells. The staining pattern of transferrin in the normal salivary gland was different from alpha 1-ACT and lactoferrin, and transferrin was positive in the cytoplasm of intercalated ducts, serous acinar and myoepithelial cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Warthin's tumor: an ultrastructural and immunohistochemical study of basilar epithelium

The cellular characteristics of the basilar epithelium in Warthin's tumor have had limited investigation. Ultrastructural examination of basal cells in 9 Warthin's tumors reveals that in addition to numerous mitochondria these cells possess a rich complement of tonofilaments. However, in three examples there are a proportion of these tonofilament-rich cells that have a narrow band of microfilaments in the peripheral cytoplasm adjacent to the basal lamina. Frozen sections of Warthin's tumor and normal salivary glands, doubly labeled with rhodamine-phalloidin for actin and monoclonal antibody 312C8-1 for cytokeratin 14, show that normal myoepithelial cells of acini and intercalated ducts have both of these filaments, as do a proportion of basal cells in the tumor. There are distinct differences in the cytokeratin polypeptide complement between normal luminal and myoepithelial cells as well as between luminal and basal cells in Warthin's tumor. Differences occur in the cytokeratin profiles between the luminal and basal cells of Warthin's tumor and comparable cells in the normal gland; however, there continue to be some similarities in the cytokeratin polypeptides of myoepithelium and the basal cells of normal salivary ducts and the basal cells of Warthin's tumor. These findings show that basal cells in Warthin's tumor are a mixed population with some capable of differentiating as myoepithelial-like cells, and that this tumor could arise from any level of the normal salivary gland duct system.

Immunohistology of adenolymphoma (Warthin's tumour): evidence for a role of vascularization in the organization of the lympho-epithelial structure

The epithelial, vascular and lymphoid components present in two cases of adenolymphoma (Warthin's tumour) were characterized by immunohistochemistry on frozen sections. Epithelial cells were positive for cytokeratin and keratin and were in close contact with numerous factor VIII related antigen-positive capillary vessels, running parallel to the epithelial basement membrane. The capillary vessels were in communication with high endothelial post-capillary venules which were often lined by HLA-DR-positive endothelial cells. The lymphoid tissue was organized in B-cell and T-cell areas. The B-cell areas consisted of B4+/To15+ B-lymphocytes admixed with DRC-1-positive follicular dendritic reticulum cells. The T-cell areas were mainly populated by T11+/T3+/T4+ lymphocytes admixed with some S-100+/HLA-DR+ interdigitating reticulum cells. Plasma cells and T8+ lymphocytes were more numerous in the proximity of the epithelium. Leu-M3+/PAM-1+ macrophages were scattered singly in the T-cell areas or were arranged in sinus-like structures around the epithelial cysts. The epithelial basement membrane, the vascular membrane and the fibrillar reticular stroma of the lymphoid tissue were immunoreactive for laminin and type IV collagen. The possibility is discussed that the accumulation of lymphoid tissue in Warthin's tumour is modulated by the epithelial cells, perhaps through their ability to organize a peculiar pattern of vascularization.

A morphometric study of cystadenolymphoma (Warthin's tumor)

This work is concerned with a morphometric analysis of cystadenolymphoma (CAL, Warthin's tumor), a growth generally found in the parotid gland. CAL is composed of various amounts of epithelium-lined cysts and of lymphoid stroma. Our results support the notion that the epithelium is the proliferating component in CAL. They also challenge the idea that CAL is a tumor, because its growth is slow and self-limiting, and occurs in a restricted space.

Hodgkin's disease occurring in a Warthin's tumor: first case report

The case of a Warthin's tumor whose lymphoid component was totally replaced by a malignant lymphoma, Hodgkin's type, is reported. The disease was characterized by a rapid downhill course, with repeated medullary relapses and subsequent episodes of bone marrow failure. Death occurred 13 months after the initial diagnosis and was due to severe visceral involvement by Hodgkin's lymphoma, as confirmed at post mortem examination.

An immunoperoxidase investigation of S-100 protein in the epithelial component of Warthin's tumor

Using the peroxidase-antiperoxidase (PAP) immunohistochemical method, we studied the epithelial component of Warthin's tumor of the human salivary gland with respect to the presence of S-100-protein-positive cells. The tumor epithelium consisted of two layers of oxyphilic cells (an apical layer of tall columnar cells and a basal layer of small cuboidal cells) and irregularly shaped, dendritic cells scattering throughout the neoplastic epithelial cells. Two types of the oxyphilic cells were devoid of the immunoreaction products for S-100 protein. However, in the epithelial layer of Warthin's tumor, S-100-protein-positive material was observed in the cytoplasm and nuclei of dendritic cells. They were more abundant in the lymphoid tissue than in the neoplastic epithelium. The morphologic appearance of these cells was identical to that of Langerhans' cells, which were absent from the normal human salivary glands. The presence of these cells, which have a special function of antigen presentation in immune responses, indicates that delayed hypersensitivity may be the main pathogenic factor in the development of Warthin's tumor.

Papillary cystic oncocytoma and Warthin's tumor of the parotid gland

A 69-year-old white female had a left superficial parotidectomy for a papillary cystic oncocytoma. The histologic appearance was identical to Warthin's tumor except that it lacked a lymphoid component. This case suggests that the general morphology of a Warthin's tumor does not depend on the presence of lymphoid tissue or association with an intra-parotid lymph node. We reviewed 50 patients with Warthin's tumors to investigate the histogenesis of the lesion. We found that most Warthin's tumors (86%) appeared to be within lymph nodes, as indicated by the presence of a lymph node capsule or sinuses. The anatomy of intra-parotid lymph nodes in glands containing Warthin's tumors has been compared with that found in 11 parotid glands containing mucoepidermoid carcinomas. So-called heterotopic ductal inclusions may actually represent the normal intimate relationship of parotid gland to intra-parotid lymph nodes.

Warthin's tumor (cystadenolymphoma) of salivary glands. A clinicopathologic investigation of 278 cases

This article reviews the detailed clinical and pathologic features of 278 cases of Warthin's tumor (cystadenolymphoma) from the files of the British Salivary Gland Tumor Panel. The tumor was found exclusively in the parotid gland, where it accounted for 14% of the total primary epithelial parotid tumors. The male predominance (1.6:1) was lower than in many earlier reports, and this observation is discussed. Some histopathologic features of both epithelium and stroma were semiquantified, and the presence of ciliated epithelium in a few tumors was confirmed. The Warthin's tumors were subclassified according to the scheme proposed by Seifert and colleagues. No examples of metaplastic Warthin's tumor were seen, but a few tumors were extensively necrotic and probably infarcted. The age distribution of patients with stroma-poor Warthin's tumor supported the concept that this variant develops by progressive adenomatous growth of typical Warthin's tumor. The histogenesis of Warthin's tumor is discussed briefly.

Extraparotid Warthin's tumor

Papillary cystadenoma lymphomatosum (Warthin's tumor) is a benign, slowly growing tumor found almost exclusively in the parotid gland or periparotid lymph nodes. Our experience with 14 cases of extraparotid Warthin's tumor (EPWT) over 22 years is presented. All cases occurred in extraparotid lymph nodes and represented 8.0% of 176 Warthin's tumors accessioned during this time. Fourteen cases of EPWT occurred in 13 patients (seven men and six women) between 41 and 77 years old. Three of the 13 patients (23%) had associated Warthin's tumor of the parotid gland. One of these patients also had a metachronous EPWT presented as a contralateral cervical mass. EPWT was discovered incidentally in six patients (46%) undergoing neck dissections for malignancies of the head and neck. Four patients (31%) presented with clinically evident solitary cervical masses. The embryologic basis for such findings is discussed. EPWT is adequately managed by conservative excision.

Cystadenolymphoma: an immunohistochemical study with special reference to Ig E and mastcells

Cystadenolymphomas (adenolymphomas) were analysed by immunohistochemical studies for the presence of immunoglobulin A, E, G and M. The distribution pattern was examined by a quantitative analysis. The relative ratio of immunoglobulins was 31.8% (Ig A), 26.6% (Ig E), 28.6% (Ig G) and 13% (Ig M). The different compartments of the lymphoid stroma were analysed separately (subepithelial area, parafollicular area, follicular area). The distribution of mast cells was studied in a parallel approach by the toluidine blue technique. These cells were found in the stroma, but also in the epithelial parts. Our results show that the subepithelial zone in cystadenolymphomas is a region of special cellular reaction (plasma cells, mast cells). The Ig E producing plasma cells and the mastcells seem to play a special role in these tumors.

Non-Hodgkin's lymphoma arising in adenolymphoma--a report of two cases

Two cases of follicle centre cell lymphoma, apparently arising within adenolymphomas of the parotid gland, are reported. These are discussed in relation to the histogenesis of adenolymphoma and their possible relationship to mucosa-associated lymphoid tissue.

Lymphoid stroma of Warthin's tumor: phenotypic analogies with gut-associated lymphoid tissue

Lymphocytes in cell suspensions and cryostat sections of Warthin's tumors (WT) have been phenotypically characterized using a battery of monoclonal and polyclonal antisera to lymphoid cell-associated antigens. The present study shows that in the WT lymphoid stroma, B cells are more numerous than T lymphocytes and include a significant percentage of surface immunoglobulin A-bearing cells. Of the T cells, the Leu 3a+ and OKT4+ lymphocytes are present in higher percentages than the OKT8+ ones. Both T-cell subsets present a topographic distribution which is similar to that found in human tonsils and gut tunica propria. Intraepithelial lymphocytes displaying an OKT8+, Leu 3a-, OKT3- phenotype are also present. These data, together with previous findings which have demonstrated that Warthin's tumor epithelium synthesizes IgA secretory piece, suggest that these cells may modulate the organization of the surrounding lymphoid stroma toward that of a mature lymphatic tissue phenotipically resembling gut-associated lymphoid tissue.

Stereologic analysis of the lymphoid stroma in parotid adenolymphoma

In 2 parotid adenolymphomas, the composition of lymphoid stroma was analysed, using stereologic point-counting methods at the electron microscopic level. In the 2 lesions, the stroma was almost identical with respect to organization and composition. Most areas of the stroma showed accumulation of mixed cell populations. On average, the latter were comprised of 5.1% fibroblastic/reticular cells, 2.7% macrophages, 68.9% small and 18.8% medium/large lymphocytes, 0.5% blastforming T-lymphocytes, 2.3% blastforming B-lymphocytes, and 1.6% plasma cells. Polymorphonuclear leukocytes and mast cells were extremely rare. Areas corresponding to the mantle zone of lymphoid follicles were found to contain 83.0% small and 15.8% medium/large lymphocytes. The present data seem to be in accordance with the speculation that the lymphoid stroma of adenolymphoma represents an immune reaction.

Immunohistochemical characterization of cellular immunoglobulins and epithelial marker antigens in Warthin's tumor

Lymphoid and epithelial cell marker studies based on paired immunofluorescence staining were performed on ethanol-fixed specimens from six Warthin's tumors of the parotid gland. A polyclonal pattern of isotype and light-chain expression was demonstrated for immunoglobulin-producing cells and afforded definitive evidence for the reactive nature of B-cell proliferation. The average percentages of IgG, IgA, IgM, IgD, and IgE immunocytes were 48.6, 38.5, 8.9, 3.3, and 0.7, respectively. The percentages of J-chain-positive cells within the first four isotypes were 11.3, 47.0, 67.2, and 64.4. Both features were more typical of immune responses in lymphoid tissues than in exocrine glands. In five of the six specimens, IgE was present in a prominent lacy pattern in some follicular centers, often extending to lymphocyte membranes of the mantle zone. Mast cells positive for IgE were seen in all cases. The two latter features indicate that type 1 hypersensitivity might contribute to the lesion. Parts of the tumor epithelium stained selectively for dimeric IgA and secretory component (SC), signifying secretory capacity. In addition, lactoferrin and carcinoembryonic antigen (CEA) occasionally were present in a narrow cytoplasmic luminal rim. Carcinoembryonic antigen was also seen in papillary epithelial projections. Lysozyme was found in isolated epithelial cells, whereas amylase was completely lacking. Except for the presence of CEA, this pattern of epithelial markers resembled that seen in striated ducts of normal salivary glands.

Medullary carcinoma of breast: an immunohistochemical study of its lymphoid stroma

Immunoperoxidase staining for IgA, IgG, IgM, and secretory component (SC) was performed on ten cases each of medullary carcinoma and infiltrating duct carcinoma of breast. Plasma cell-rich stroma of medullary carcinoma was found to contain predominantly IgA plasma cells. Tumor cells also contained IgA and SC. In contrast, the few plasma cells of infiltrating duct carcinoma were found to be predominantly IgG type, and the tumor cells contained none or very small amounts of IgA and SC. Because the presence of IgA plasma cells and IgA and SC in lining epithelial cells are characteristic features of organs of the secretory Ig system, these findings in medullary carcinoma may suggest a good degree of functional differentiation of these tumor cells and correlate well with the well-known favorable prognosis associated with this tumor.