Lymphomas and pseudolymphomas of the alimentary tract. An immunohistochemical study with clinicopathologic correlations

EBV-associated anorectal lymphomas in patients with acquired immune deficiency syndrome

Primary lymphomas of the gastrointestinal tract represent 9% of all non-Hodgkin lymphomas, and of these only 3% arise in the rectum or anus. In contrast to their rare occurrence in the general population, the incidence of anorectal lymphomas in patients with acquired immune deficiency syndrome (AIDS), particularly homosexual patients, may be as high as 26% as reported in our own series of AIDS-associated lymphomas. To determine the characteristics of this entity, we studied 15 cases of primary anorectal lymphoma in AIDS patients and compared them with four cases of anorectal lymphoma unrelated to AIDS. The cases in our study were also compared with the reports of rectal lymphoma in the medical literature over the past 30 years. In the present series, the AIDS patients were all male with a median age of 34 years, human immunodeficiency virus (HIV)-positive, with homosexuality as the main risk factor. The four non-AIDS patients included a woman and had a median age of 66.5 years. Histologically, the anorectal lymphomas in AIDS patients were all high grade, predominantly immunoblastic, and polymorphous. In the non-AIDS patients, only two of four lymphomas were high grade, including one Burkitt type. All tumors were of B-cell phenotype. In the AIDS-associated anorectal lymphomas, the presence of Epstein-Barr virus (EBV) in a latent form was demonstrated by an abundance of Epstein-Barr-encoded RNA (EBER) in 14 of 15 cases and latent membrane protein (LMP) in four cases. All anorectal lymphomas unrelated to AIDS were negative for EBV. The unusual anorectal location of AIDS-associated lymphomas is explainable by the high incidence of preceding traumatic lesions and chronic infections in the area. As a result, EBV-carrying B cells may be attracted to the field providing the cell population that, under the conditions of immune deficiency, is able to give rise to high-grade lymphomas.

Estimation of silver-binding nucleolar organizer regions (AgNORs) in lymphoproliferative disorders of gastrointestinal tract

We quantified nucleolar organizer regions demonstrable by silver staining technique (AgNORs) in six cases of reactive lymphoid hyperplasia (RLH), and in 14 low-grade B-cell lymphomas (mucosa-associated lymphoid tissue (MALT) 5, centrocytic 3, centroblastic-centrocytic 6) and 49 high-grade B-cell lymphomas (centroblastic 44, immunoblastic 3, Burkitt's one, large cell anaplastic one). The pooled mean AgNOR number in low-grade B-cell lymphomas was significantly higher than that in RLH, and significantly lower than that in high-grade B-cell lymphomas. There was a statistically significant difference between RLH versus centroblastic-centrocytic lymphoma in pooled mean AgNOR number and in RLH versus centrocytic lymphoma but not in RLH versus MALT lymphoma. The AgNOR numbers in the cellular components of RLH were also analyzed. The follicle center centroblasts of RLH exhibited a significantly higher pooled mean AgNOR number than other kinds of lymphoid cells in RLH. Furthermore, AgNOR numbers of gastrointestinal lymphomas were compared with those of cellular elements in RLH. There was a statistically significant increased AgNOR number of centroblastic lymphoma when compared with neoplastic centroblasts in centroblastic-centrocytic lymphoma and follicular centroblasts in RLH. By contrast, there was no significant difference in AgNOR numbers between MALT lymphomas and interfollicular lymphocytes, mantle zone lymphocytes or follicular centrocytes in RLH, respectively. This study demonstrated a similar increase when non-Hodgkin's B-cell lymphomas in gastrointestinal tract were compared with histogenetically related cellular elements of RLH. AgNOR counting might be useful adjunct in the classification and grading of lymphoproliferative disorders in gastrointestinal tract.

Immunophenotypic analysis of extranodal non-Hodgkin's lymphomas in the oral cavity

Fifty cases of extranodal non-Hodgkin's lymphoma arising in the oral cavity were reclassified using the updated Kiel classification. In order to determine the antigenic phenotype of the proliferating cells in oral lymphoma, we used a panel of paraffin effective antibodies that are known to react with lymphocyte- and histiocyte-associated antigens. The median age of the patients was 53 years, with a male predominance (M:F = 1.9: 1). The great majority of oral non-Hodgkin's lymphomas were B-cell lymphomas. There were 12 low-grade B-cell lymphomas (comprising one mucosa-associated lymphoid tissue, four centrocytic and seven centroblastic-centrocytic lymphomas) and 25 high-grade tumors (comprising 17 centroblastic, two immunoblastic, two Burkitt's and four lymphoblastic lymphomas). All 37 B-cell malignancies showed reactivity for L 26 and KiB 3. A monotypic immunoglobulin staining pattern, as revealed by light chain restriction, was found in 21 cases (57%) of the non-Hodgkin's lymphomas confirming their B-cell origin. Furthermore, monotypic staining for kappa-chain predominated (16/21 kappa, 5/21 lambda). Only a small number (6 cases) was of T-cell lineage and all cases showed positive reaction for UCHL 1, MT 1 and DFT 1. In one of six T-cell lymphomas, Ber-H 2 positive anaplastic large cell lymphoma was detected. Such a case was documented for the first time in the primary extranodal non-Hodgkin's lymphoma of the oral cavity. Five cases could be assigned with certainty to the histiocytic system. These cases were positive for cathepsin D and KP 1 LN 3, which recognized Ia (HLA-DR) antigens, was demonstrated most frequently in high-grade B-cell lymphomas, T-cell lymphomas and true histiocytic lymphomas.

Low grade B cell mucosa associated lymphoid tissue lymphoma of the stomach: clinical and endoscopic features, treatment, and outcome

A retrospective study of the clinical and endoscopic features of low grade gastric lymphomas of mucosa associated lymphoid tissue (MALT) in 16 patients together with treatment and outcome was undertaken. Immunohistochemical studies of fresh tissue easily distinguished MALT lymphoma from benign reactive lymphoid hyperplasia (pseudolymphoma) and showed that tumour cells had the characteristic phenotype indicative of their origin from MALT. Persistent epigastric pain was the main presenting complaint, and was often associated with acute bleeding, anaemia, or weight loss. Eight patients had a past history of recurrent peptic ulcers or gastritis. The endoscopic appearance suggested malignancy in only half the cases and was compatible with gastritis or a benign peptic ulcer in the remainder. There was extragastric involvement of other mucosal sites in eight patients (mainly the lung, but also the parotid gland and small bowel), but rarely was bone marrow and never the spleen or peripheral lymph nodes affected. Conservative treatment with long term cyclophosphamide was effective in both stage I and stage IV disease, and all the patients are alive after a median follow up of 4.5 years. These findings confirm that low grade gastric MALT lymphomas are usually indolent tumours with non-specific endoscopic aspects and show that dissemination to other mucosal sites was more frequent than previously reported. Monochemotherapy could be an effective alternative treatment to surgery.

Clonal Ig-gene rearrangement in some cases of gastric RLH detected by PCR method

Clonal immunoglobulin (Ig) heavy chain gene rearrangement in gastric reactive lymphoid hyperplasia (RLH) cases was investigated by means of the 'double' polymerase chain reaction (PCR) using formalin-fixed and paraffin-embedded tissue. Rearranged DNA sequences, formed by combinations of variable (VH) and joining (JH) regions, were amplified with oligomeric primers. One microgram of DNA extracted from formalin-fixed and paraffin-embedded tissue was applied as the 'first PCR' template and one ten-thousandth of the first PCR product was used as the 'second PCR' template. As a control study for the double PCR method, DNA isolated from frank B cell gastric malignant lymphomas was assessed. Clear single bands between 100 and 150 base pair markers in length were evident on agarose gel electrophoresis in 10 out of 13 cases (76.9%) of malignant lymphomas while 2 out of 22 cases (9%) of RLHs revealed clear single bands of the same length, suggesting malignant lymphomas; however, no histologic features of malignant lymphomas were present. It is concluded that even gastric RLH cases satisfying histopathologic criteria for benign lymphoid hyperplasia may contain occult monoclonal B cell populations suggesting a continuous and progressive spectrum of lesions contributing to B cell neoplasia.

Molecular-genetic analysis of ocular adnexal benign lymphoid hyperplasias by a two-step polymerase-chain-reaction

Twelve biopsied ocular adnexal benign lymphoid hyperplasias (OABLH) satisfying benign histological criteria were investigated for clonal immunoglobulin (Ig) heavy-chain gene rearrangement by means of a two-step polymerase chain reaction (PCR) method using formalin-fixed and paraffin-embedded tissue. Of the 12, 4 (33%) demonstrated clear single bands of the rearranged gene for the Ig heavy-chain, of between 100 and 150 base pairs. The selected cases were all free of malignant lymphoma and all of the lesions were small (2 x 2-22 x 6 mm; median 4.5 x 3 mm). Histopathological and cytological features were not essentially different between monoclonal and non-monoclonal examples. Immunohistochemistry was of little benefit in separating the two. It is concluded that OABLH demonstrating a benign clinical course frequently contain monoclonal B cell populations suggesting a continuous progressive spectrum of lesions in B cell neoplasia. In addition, the significance of molecular-genetic analysis for OABLH and the utility of the two-step PCR method should be emphasized.

Histopathological and immunohistochemical study of atypical lymphoid hyperplasia and benign lymphoid hyperplasia of the stomach

We propose dividing histologically reactive lymphoid hyperplasia (RLH) of the stomach into two categories: atypical lymphoid hyperplasia (ALH), characterized by abnormal follicular architecture and infiltration of atypical lymphoid cells, and benign lymphoid hyperplasia (BLH), where normal follicular patterns are preserved and no atypical cells are found. Using twenty RLH cases (10 ALHs and 10 BLHs), both categories were compared from histopathological and immunohistochemical aspects. Macroscopic division into superficial, thick-walled and nodular types revealed most ALH (80%) to be superficial in character whereas in BLH superficial and thick-walled types were almost equally represented. Lesion size tended to be larger in ALH (greater than 6.1 cm) than in BLH (6.0 cm greater than) cases. As for prognosis after gastrectomy, both categories were favorable. On immunohistochemistry, ALH tended to be strongly labeled by B lymphocyte markers as compared to BLH, where only a weakly positive reaction was expressed. Infiltration of cells labeled by T lymphocyte markers was less conspicuous in ALH than in BLH. From these data, we concluded that ALH and BLH are two distinctive categories of lesion and that ALH has characteristics similar to these demonstrated by malignant lymphoma.

Primary gastric non-Hodgkin's lymphoma. A retrospective clinico-pathological study

Prognostic factors and treatment results were analysed in 72 consecutive patients with primary gastric lymphoma treated between 1970 and 1985. There were 37 patients in stage IE, 17 in IIE, 3 in IIES and 15 in stage IV. Histopathological re-evaluation and classification according to the TNM system were performed. We found that disseminated disease (stage IV), serosal penetration (T3), involvement of adjacent organs (T4) and extensive abdominal lymph node involvement (N3) were poor prognostic factors. Neither histological malignancy grading, nor the appearance of lympho-epithelial lesions were significantly associated with relapse-free survival. Forty-six patients with 'limited localized' disease (stage IE, IIE, N3 excluded) received potentially curative treatment (surgery, radiotherapy, chemotherapy or combinations thereof), of whom 85% remained relapse-free. Thirty-four patients did only get local treatment (surgery and/or radiotherapy) with curative potential, the relapse-free survival rate was 85%. We conclude that primary gastric lymphoma stage IE and IIE (N3 excluded) is often a truly localized disease that can be cured with local therapy.

Gastric "pseudolymphoma" with restricted light chain expression in a patient with obscure gastrointestinal blood loss

We present a case report of a gastric "pseudolymphoma" (GL) that exhibits restricted light chain expression and, therefore, illustrates the dilemma encountered when histologically benign lesions have phenotypic abnormalities suggesting malignancy. For many years this lesion has been considered usually benign; however, recent reports such as this one demonstrate immunologic signs of monoclonality in an otherwise histologically benign lesion. This finding challenges our assumptions as to the nature of this lesion and our definition of cancer. The lesion also displays "Castleman-like" features (angiofollicular hyperplasia) as well as "common inflammatory" germinal centers. In addition we briefly review the literature.

A case of intestinal T-cell lymphoma with repeated episodes of perforation

A case of intestinal cytotoxic/suppressor T-cell lymphoma with repeated episodes of perforation was seen in a 77-year-old Japanese male who was admitted complaining of severe abdominal pain accompanied by high grade fever. Surgery revealed diffuse peritonitis due to perforation in the sigmoid colon. After a loop sigmoid colostomy the patient recovered to some degree. Seven days later, however, another perforation occurred. Several aneurysmal swellings accompanied by perforation in the small intestine, forming a mass of 5 x 5 cm, were seen. Although the patient tolerated this operation, generalized emaciation proceeded and the patient died 10 days late. Histological examination at the second operation showed diffuse medium-sized lymphoma of the Lymphoma Study Group (LSG) classification infiltrating the entire depth of the intestinal wall. Destruction of muscle cells was prominent. An immunohistochemical study using fresh frozen material was positive for CD3, and CD8. This marked destruction of the muscle layer by lymphoma cells may be associated with repeated episodes of perforation.

The role of the endoscopic biopsy in the diagnosis of gastric lymphoma: a morphologic and immunohistochemical reappraisal

Forty-three endoscopic biopsies from 29 patients with confirmed gastric lymphoma (GL) were analyzed retrospectively to establish the morphologic criteria of greatest diagnostic significance. An average of 10 tissue samples was obtained at each endoscopy. In 44% of the cases, lymphoma was discovered in only one or two of the tissue portions. Eighteen lymphomas were primary, six were probably primary, and five were generalized. The diagnosis of lymphoma was originally suspected or established in 46% of the biopsies. However, a review of the histologic sections indicated that the changes, either diagnostic of or compatible with lymphoma, were present in 75% and 18% of the sections, respectively. Most diagnostic errors consisted of confusion with diffuse lymphoid infiltrates in chronic gastritis and/or peptic ulcer, and less frequently with poorly differentiated carcinoma. In those cases confused with chronic gastritis or peptic ulcer, biopsies showed centrocyte-like cells of the standard type or small lymphocytes which produced: (1) a marked increase in density of the lymphoid infiltrate in the gastric mucosa, (2) massive substitution of gastric glands by lymphoid infiltration, and (3) a collection of lymphocytes infiltrating and partially destroying isolated glands (lymphoepithelial lesion). From 48 biopsies having intense benign lymphoid infiltrates, three were interpreted (by means of a blinded study) as compatible with GL. In poorly differentiated neoplasms (blastic and pleomorphic types), cytologic features were sufficient to diagnose GL or malignant neoplasms; immunohistochemical techniques were useful to define their lymphoid nature. It is concluded that many GLs can be suspected or correctly diagnosed by routine endoscopic biopsy.

Primary malignant non-epithelial tumours of the thoracic oesophagus and cardia in a 25-year surgical material

During 25 years, 708 patients with primary malignant tumours of the thoracic oesophagus (n = 376) or cardia (n = 332) were referred to our department. Two hundred and forty-nine patients had squamous cell carcinoma and 425 adenocarcinoma. The other 34 tumours, which were primarily classified as undifferentiated carcinoma, malignant carcinoid or non-epithelial, were re-evaluated by means of a second microscopic histologic examination and immunohistologic investigation. This showed primary malignant non-epithelial tumours in seven patients (0.99%): two malignant melanomas, one leiomyosarcoma, one malignant fibrous histiocytoma in the oesophagus (1.06%), two malignant lymphomas, and one malignant melanoma in the cardia (0.90%). All but two of the patients with non-epithelial malignant tumours were 67 years of age or older, and oesophagogastrectomy was performed in all. All tumours were 5 cm or more in diameter (median, 8 cm). Distant metastases were found in three cases. Five died of postoperative complications, one of cancer recurrence 7 months after the operation, and one of an unrelated cause without cancer recurrence 16 months postoperatively. Except for two of the melanomas, the diagnosis was not established until histologic examination of the surgical specimen was performed and, for the third melanoma and the malignant fibrous histiocytoma, not until the present re-evaluation. The characteristics of these seven tumours are discussed, and the importance of obtaining a correct diagnosis from endoscopic biopsy specimens is emphasized.

Primary gastric lymphoma: a prospective analysis of 12 cases and review of the literature

The clinicopathological features of 12 cases of primary lymphoma of the stomach are reviewed, and the efficacy of various treatment modalities is evaluated. The presenting symptomatology and the radiological signs were found to be similar to those of gastric carcinoma. Gastroscopy and computed tomography (CT) proved to be effective diagnostic and staging tools. There were two patients of stage I, seven patients of stage II, and three patients of stage IV. Multimodal therapy involving judiciously combined surgery, radiation therapy, and chemotherapy produced early complete remission in all the nine patients with localized disease, and all of them are disease-free at a minimum follow-up period of 12 months. These results are irrespective of whether surgery formed part of the treatment regimen. The relevant literature is reviewed, and the present status of the efficacy of nonsurgical therapy is evaluated.

Primary gastrointestinal lymphoma in childhood (up to 18 years of age). A morphological, immunohistochemical and clinical study

A group of 47 patients up to 18 years of age, with primary non-Hodgkin's lymphoma of the gastrointestinal tract, were investigated. The lesions were located in the stomach (n = 2), small intestine (n = 17), the ileocecal region (n = 20), the large intestine (n = 7), and multifocally in the small and large intestines (n = 1). Of the patients, 41 were male and 6 were female; their age at presentation ranged from 2 to 18 years. All of the cases belonged to the high-grade malignancy group of the updated Kiel classification. Burkitt's lymphoma was the most frequent histological type (n = 35), followed by centroblastic lymphoma (n = 3), immunoblastic lymphoma (n = 2), lymphoblastic lymphoma (n = 1), and large-cell anaplastic lymphoma (n = 1). Five of the patients had high-grade unclassified B-cell lymphoma. Of all the lymphoma types 41 cases (87%) were positive for Ki-B3 (a B-cell marker). Expression of monoclonal immunoglobulin was demonstrated in 8 of 35 cases (23%) of Burkitt's lymphoma, in all 3 cases of centroblastic lymphoma, in both cases of immunoblastic lymphoma, in the single case of lymphoblastic lymphoma, and in all 5 cases of high-grade unclassified B-cell non-Hodgkins lymphoma. Most of the Burkitt's lymphomas showed the light chain lambda (7/8). According to the staging classification of Murphy (N Engl J Med 299:1446-1448, 1978), 12% of the 34 cases available were stage IE, 44% stage IIE, 38% stage IIIE, and 6% stage IVE. Of these 34 patients, 13 died with lymphoma within 1 year after diagnosis. The survival rate for the 19 patients in stages I and IIE at 2 years was 83%, while for the 15 patients in stages III and IVE it was 32% (P less than 0.05). A significant difference in survival was found between the 13 patients with primary involvement of the small intestine and the 20 patients with primary involvement of the large intestine and ileocecal region, the latter showing a better prognosis. Lymphoma type did not significantly influence survival. Our findings indicate that the stage at diagnosis and the primary site are important prognostic features in gastrointestinal non-Hodgkin's lymphoma.

Prognostic factors in primary gastrointestinal non-Hodgkin's lymphoma. A multivariate analysis, report of 106 cases, and review of the literature

The authors have reviewed 106 cases of primary gastrointestinal non-Hodgkin's lymphoma (GI-NHL) treated at the Institut Gustave-Roussy (IGR), France, between 1975 and 1986. The occurrence was 55 in the stomach, 26 in the small intestine, ten ileocecal, seven in the large intestine, and eight patients had multiple involvement. Patients were clinically staged according to the Ann Arbor staging system using the modification of Musshoff for Stage IIE. All histologic material of the 106 patients were reviewed and graded according to the Working Formulation (WF) and the Kiel classifications. Most patients received combination chemotherapy as part or all of their primary treatment program (95 patients, 90%). Seventy five patients (71%) had a multimodality treatment. The overall 5-year survival rate was 60%. Sixteen variables were tested by univariate analyses for prognostic influence on survival. Of these, only clinical stage (P less than 0.001), the achievement of initial complete remission (CR) (P less than 0.001), erythrocyte sedimentation rate (ESR) (P = 0.01), mesenteric involvement (P = 0.03), and serosal infiltration (P = 0.05) were significant prognostic factors. Important variables were tested by a multivariate analysis using the Cox model taking into account different treatment modalities. Only three variables entered the regression analysis at a significant level: clinical stage (P = 0.02), surgical resection (P = 0.03), and histologic grade (Kiel) (P = 0.04). When the achievement of initial CR was introduced into the model, it was the most significant variable (P less than 0.001) whereas all other variables became nonsignificant except for the histologic grade (Kiel) (P = 0.004). Based on results of the multivariate analyses we propose two prognostic classifications of patients: one at the initial evaluation depending on clinical stage, surgical resectability, and histologic grade (Kiel); the other at the end of primary treatment depending on the achievement or not of CR and the histologic grade.

Gastric small lymphocytic proliferation with immunoglobulin gene rearrangement in pseudolymphoma versus lymphoma

The nature of gastric infiltrates consisting primarily of benign-appearing small lymphocytes is at present a controversial issue. Earlier reports of gastric lymphoma developing in gastric pseudolymphoma and more recent immunohistochemical studies demonstrating monoclonal B-cell populations in pseudolymphoma suggest that at least some cases represent low-grade lymphomas or clonal precursor lesions that may develop into lymphoma. Observations of a small lymphocytic infiltrate arising in the region of a gastric ulcer that lacked definitive morphologic evidence of malignancy (lymphoma) but was clearly a monoclonal B-cell proliferation by immunohistochemical and gene rearrangement studies support the notion that some gastric lymphoproliferative lesions that histologically have been called pseudolymphomas may include one or more clonal lymphoid expansions. A histopathologic/molecular model suggesting a potential pathway for the development of morphologically recognizable lymphoma from benign-appearing small lymphocytic infiltrates is presented, and the concept that for a variety of lymphoid proliferations clonality and malignancy may not be synonymous is discussed.

Gastrointestinal lymphoma in 20 dogs. A retrospective study

The records of 20 dogs with histopathologically diagnosed gastrointestinal (GI) lymphoma (LSA) evaluated between 1970 and 1984 were reviewed. Fifteen dogs were considered to have primary GI LSA, while five dogs had GI involvement in association with the multicentric form. Most clinical and laboratory findings were nonspecific, but positive-contrast upper GI radiography was suggestive of GI LSA in all of the dogs evaluated. Nine dogs had extensive lymphocytic-plasmacytic inflammatory infiltrates around the neoplastic foci, resulting in difficulty in obtaining a diagnosis of GI LSA when samples were obtained by endoscopy.

The non-Hodgkin's lymphomas: old and new thinking

Knowledge of non-Hodgkin's lymphomas has increased enormously in the last 10-15 years. The various types are considered to reflect the normal immunological processes that take place in the lymphoid tissue after antigenic challenge. This concept, which states that non-Hodgkin's lymphomas are neoplastic counterparts of normal processes, has implications for morphology, immunology and clinical behaviour. Based on this concept, as well as on immunohistological and functional data, a hypothetical scheme of B-cell development is proposed. The relation to normal physiology also holds for lymphomas localized outside the lymph nodes. Normal structure and function in two important extranodal lymphoid tissues, the gastrointestinal mucosa and the skin-associated lymphoid tissues, are related to the lymphomas arising in these sites. This relation and some of its implications are discussed, with special reference to the important processes of homing and recirculation of lymphocytes.

Anaplastic solitary extramedullary plasmacytoma of the cecum. Report of a case confirmed by immunoperoxidase staining

Solitary extramedullary plasma cell tumors, although uncommon, have been reported with increasing frequency over the last few years. Approximately 5 to 10 percent of the tumors arise in the gastrointestinal tract. This report demonstrates that a solitary anaplastic cecal extramedullary plasmacytoma can mimic a polypoid carcinoma, both grossly and, to an extent, microscopically. Immunoperoxidase stains for cytoplasmic immunoglobulin proved useful in establishing the correct diagnosis.

Gastrointestinal non-Hodgkin's lymphoma

Seventy-two patients with gastrointestinal non-Hodgkin's lymphoma treated between 1952 and 1980 are reviewed. The small intestine was involved in 49% of cases and the stomach in 29%. Surgical resection of the tumour was performed whenever feasible. Radiotherapy was used either adjuvantly or for incompletely excised tumours and chemotherapy was more often reserved for advanced, unresected disease. The overall 5 year survival was 36% and the 5 year relapse free survival was 22%. Forty-one (57%) patients relapsed of whom 33 (80%) subsequently died of non-Hodgkin's lymphoma. The histology in each case was reviewed using the British National Lymphoma Investigation criteria and 94% of cases were reclassified as Grade 2 non-Hodgkin's lymphoma.

Application of anti-leukocyte common antigen and anti-cytokeratin antibodies to the biopsy diagnosis of gastric large cell lymphoma

Definitive diagnosis of gastric large cell lymphoma and its distinction from anaplastic carcinoma in endoscopic biopsy material may be problematic. To assess the utility of immunohistochemical studies in routinely processed, paraffin-embedded tissue in this situation, we applied immunostaining for leukocyte common antigen (LCA) and cytokeratin in 17 cases diagnosed on biopsy as undifferentiated malignant tumor but proved on resection to be primary gastric large cell lymphoma. Clinical and endoscopic features failed to distinguish lymphoma from carcinoma in these cases. Immunoreactivity for LCA occurred in 15 cases (88 per cent) and was correctly and readily interpreted on blinded evaluation. Open review increased the yield to 16 cases (94 per cent). Tumor cells were uniformly negative for cytokeratin; however, staining of adjacent epithelium for cytokeratin provided additional confirmation of the lymphoid nature of the tumor. The one case in which excessive background staining precluded interpretation consisted of a single biopsy specimen of necrotic tumor. We conclude that antibodies to LCA and cytokeratin are sensitive, specific, and reliable diagnostic adjuncts that are useful in the definitive biopsy diagnosis of gastric large cell lymphoma.

Lymphoid stromal reaction in gastrointestinal lymphomas: immunohistochemical study of 14 cases

The lymphoid stromal reaction, particularly the T lymphoid reaction, was studied immunohistochemically on cryostat sections in 14 cases of primary gastrointestinal B lymphomas, and compared with the type and distribution of lymphoid cells in three cases of gastric lymphoid hyperplasia. A pronounced T lymphoid reaction, mainly of the T helper phenotype, occurred in both lesions. Most of these T cells bore HLA-DR antigens, but only a few of them had the receptor for interleukin 2. The T lymphoid reaction was observed inside the lymphomas in seven of a total of 14 cases, and around the lymphomas in four of the six cases clinically classified as stage I. Perivascular mucosal and submucosal nodules, entirely composed of T cells, seemed characteristic of gastric lymphoid hyperplasias. A T lymphoid reaction in lymphoid hyperplasias suggests an amplification of the cell mediated immune response; in lymphomas it could represent a host reaction against the lymphomatous infiltrate, therefore favouring a better prognosis.

Lymphoid follicles appearing in gastric mucosa, especially in reactive lymphoid hyperplasia and malignant lymphoma

Histopathological analysis of reactive lymphoid hyperplasia (RLH) and malignant lymphoma (ML) of the stomach was made based on the observations of lymphoid follicles appearing in gastric mucosa. The materials used for study consisted of 28 stomachs without RLH or tumor obtained from either operation or autopsy, 18 stomachs with RLH, and 46 stomachs with ML. Lymphoid follicles appeared soon after birth, increased with mucosal atrophy, and decreased in mucosa with intestinal metaplasia. They possessed a sinusoidal structure and appeared in the muscularis mucosae intimately related to the lymphatic flow. Excepting for the significant proliferative nature, the structural evolution of lymphoid follicles in RLH was similar to that in atrophic mucosa. They showed, however, a wide spectrum of changes containing cases with simple reactive changes to those with prelymphomatous changes. As to ML, the large cell type demonstrated a destructive proliferation, while both small and medium-sized cell types showed proliferation and infiltration preserving their original structure. In the superficial type, ML was frequently accompanied by RLH and mucosal atrophy. The histological features of ML consisted of not only the characteristics of tumor cells but also the proper mucosal changes including lymphoid follicles.

Lymphoma immunotyping by paraffin immunoperoxidase and cell suspension methods--a comparative study

Immunoperoxidase staining incorporating an enzyme digestion step was performed on paraffin sections of 84 biopsy cases of lymphoproliferative disorders. Monoclonality was demonstrated in 100% of plasmacytomas and related tumours, and in 66% of non-Hodgkin's lymphomas. In 83% of lymphomas the immunoglobulin class was IgM and the light chain distribution was kappa 64% and lambda 36%. Polyclonality was found in 89% of cases of reactive lymphoid hyperplasia and within Reed-Sternberg cells in 55% of cases of Hodgkin's disease. Similar results were obtained by dispersed cell studies in 56 overlapping cases. The concordance rate between the two methods in 40 cases of non-Hodgkin's lymphoma was 67.5%. Reasons for the inconsistencies are discussed. Immunoperoxidase staining of enzyme digested paraffin sections is useful in the diagnosis of B cell lymphoproliferative disorders with a particular role in centres where cell suspension studies are not available or when there is no access to fresh tissue.

Immunohistochemistry of primary gastrointestinal lymphomas: a study of 76 cases

A retrospective study of 76 primary gastrointestinal lymphomas utilizing an avidin: biotinylated horseradish peroxidase complex (ABC) technique demonstrated 22 B-cell lymphomas, including two associated with alpha-heavy chain disease. Seven cases were classified as true histiocytic lymphomas based on a positive reaction for one or more of three histiocytic enzyme markers utilized, predominantly alpha-1-antitrypsin and alpha-1-antichymotrypsin. However, in 20 cases, an intense admixture of reactive histiocytes was noted and these cells stained preferentially for the enzyme, lysozyme. Twenty cases, which stained for both kappa and lambda light chains and positively or negatively for albumin, could not be classified and 27 cases failed to stain with any of the antisera utilized.

Focal malignant lymphoma in gastric pseudolymphoma. Histologic and immunohistochemical study of a case

The authors report a case of a focal malignant lymphoma (ML), plasmacytic type, supervening in a gastric pseudolymphoma (PSL), diagnosed 6 years before and closely followed up. The diagnosis was made on endoscopic biopsy findings and confirmed by subtotal gastric resection. Immunohistochemical studies were performed both on surgical material and, retrospectively, on the initial series of biopsy specimens. The majority of the lymphoid cells of the PSL expressed the same immunoglobulin heavy and light chains as the cells of the ML, which were characterized by the presence of monoclonal mu and kappa chains. These results suggest a close relationship between the PSL and ML, and support the hypothesis of the prelymphomatous nature of the gastric pseudolymphoma. The possible existence of focal malignant lesions among PSL suggests reevaluation of the role of surgical resection in its management. Endoscopic examination allows its diagnosis on biopsy material, but it remains difficult to detect focal ML among the benign-appearing lesion. For this reason, surgical resection must be always performed, regardless of the circumstances of the initial diagnosis, both as a means of final diagnosis and as therapy.

Gastrointestinal lymphoma

The gastrointestinal tract is the commonest site for primary extranodal malignant lymphoma. Despite this, gastrointestinal lymphomas are rare and present diagnostic and conceptual challenges. Principal among these are the differential diagnoses of malignant lymphoma and carcinoma and malignant lymphoma and pseudolymphoma, especially in the stomach; the nature of Mediterranean lymphoma and of the lymphoma complicating celiac disease; and the conceptual basis for differentiation of follicular centre cell lymphomas in the intestine.

Primary gastrointestinal non-Hodgkin's lymphomas. A retrospective clinicopathologic study of 150 cases

The records of 150 primary gastrointestinal (GI) lymphomas in adults collected from 1974 to 1982 at the Department of Pathology, University of Vienna, were reviewed. One hundred thirty-three cases of malignant lymphomas (ML) were analyzed with respect to histologic type, presenting tumor stage, and clinical course, as well as for factors influencing prognosis. The histologic type of ML as assessed by the Working Formulation and the Kiel, the Lukes and Collins, and the Rappaport classifications showed only a minor influence on prognosis. MLs of follicular center cell origin prevailed in the stomach and large cell, immunoblastic MLs prevailed in the bowel. Immunoperoxidase studies indicated a B-cell nature of GI MLs and demonstrated intracytoplasmic IgM kappa or lambda in most of the MLs of the small lymphocytic, plasmacytoid, and immunoblastic type, respectively. The 105 cases of gastric MLs represented 3.6% of all malignancies of the stomach collected during the study period. Clinical symptoms preceded the diagnosis by 4.4 months on average, and endoscopic biopsy specimens indicated malignancy in 78%. Presenting tumor stages of gastric MLs according to the Ann Arbor staging system were Stage I in 20%, Stage II in 76.2%, and Stage IV in 3.8%. The 28 cases of intestinal ML localized in the small and large bowel without any site prevalence presented with Stage I in 14%, Stage II in 82%, and Stage III in 4%. Tumor resection was performed in 90% of all cases and was followed by multiagent therapy in 53%. Radical tumor resection was obtained in 58% of the gastric MLs and only 28.6% of the intestinal MLs and was closely related to tumor stage. Statistical analysis demonstrated a significant influence of the presenting tumor stage on prognosis as expressed by the overall 2-year survival rate of 70% for Stage I versus 39% for Stage II ML. In addition, Stage II1 according to Musshoff et al. run a better course than II2 as shown by the disease-free 2-year survival rate of 49% versus 15%, respectively. Radical tumor resection was a major determinant of survival and cure of disease as exhibited by the disease-free 2-year survival rate of 57% after radical resection versus 8% after nonradical resection of ML. Finally, diffuse tumor growth and tumor penetration of the gastric wall beyond serosa decreased the survival rates.

Primary gastrointestinal malignant lymphomas. A morphologic and immunohistochemical study

Thirty-nine primary gastric and 22 intestinal malignant lymphomas collected from 1969 to 1980 have been studied morphologically and immunohistochemically. Eighteen of the 61 gastrointestinal lymphomas were of low-grade malignancy (9 lymphoplasmacytoid/cytic, 3 centrocytic, 6 centroblastic/centrocytic) and 43 were of high-grade malignancy (14 centroblastic, 7 lymphoblastic, 22 immunoblastic malignant lymphomas) according to the Kiel classification. The peroxidase-antiperoxidase (PAP) method was used in 53 of the 61 cases. Twenty-seven of them revealed a monoclonal positivity for intracytoplasmic IgS: kappa light chains in 18 and lambda light chains in 7 cases. Two cases represented alpha chain disease, revealing only a heavy chain positivity. The most frequent staining pattern of the lymphoma cells was that of kappa/mu. Cells with a mixed centrocytic and plasma cell configuration (centrocytoid plasma cells) proved to be positive for intracytoplasmic IgS. Lymphoma cells of all tested cases proved to be negative for all histiocytic markers. Histologically and immunohistochemically, the Greek cases of primary gastrointestinal malignant lymphomas seem to resemble "western" type lymphomas.

Lymphomas of the mucosa-associated lymphoid tissue. Signet ring cell lymphomas presenting in mucosal lymphoid organs

Four cases of lymphoma are reported which were postulate to have developed from neoplastic transformation of the lymphoid cells of the mucosa-associated lymphoid tissue (MALT). This contention is primarily based on two observations: the peculiar "homing" tendency of these lymphomas and the immunoglobulin isotype. Both properties are characteristic of the lymphoid cells of the MALT. These lymphomas can also be identified by their histologic structure (signet ring cell lymphomas) and their presentation in an MALT organ. These lymphomas are probably separable from other lymphomas proposed to arise from lymphocytes of the gut-associated lymphoid system (GALT).

Gastric pseudolymphoma. A challenging clinical problem

Gastric pseudolymphoma is a benign inflammatory condition that is usually associated with chronic gastric ulcer and often mimics gastric carcinoma or malignant lymphoma. Our experience with 12 histologically documented gastric pseudolymphomas at the Medical College of Virginia is presented with an emphasis on the approach to both diagnosis and surgical management. Preoperative diagnoses in this series ranged from benign gastric ulcer to gastric cancer. Treatment was by gastric resection in all cases and it included, as a minimum, antrectomy and excision of the lesion with an adequate gross margin. Of 11 cases with adequate follow-up, there are eight asymptomatic patients without recurrence and one patient who died of other causes without recurrence 5 years after gastrectomy. One patient developed recurrent pseudolymphoma in the proximal gastric remnant 39 months after a distal subtotal gastrectomy for pseudolymphoma. Another patient subsequently developed Hodgkin's disease of the gastric remnant, with regional lymph node and liver involvement, and died 35 months after the earlier subtotal gastrectomy for pseudolymphoma. Our clinical experience with this confusing and uncommon entity is compared with that previously reported in the medical literature.

Epitheliotropic lymphoma of the small bowel. Report of a fatal case with cytotoxic/suppressor T-cell immunotype

The authors report the clinical, pathologic, and immunologic features of a case of jejunal cytotoxic/suppressor T-cell lymphoma associated with intractable malabsorption. Histologically, the tumor exhibited striking involvement of small bowel surface and glandular epithelium, and of epithelium in sites of disease dissemination. This epitheliotropism consisted of both cell clusters resembling Pautrier 's microabscesses and single cells within epithelium. Grossly, the jejunal mucosal fold pattern was completely obliterated by lymphoma which formed miliary nodules and multiple distinct tumor masses. Despite aggressive chemotherapy the patient developed widespread disease, and died 11 months after presentation. At autopsy, in addition to disseminated lymphoma, there was a notable activation of hematopoiesis evidenced by extensive extramedullary hematopoiesis and bone marrow hypercellularity. Many lymph nodes spared by the lymphoma showed a polyclonal proliferation of plasma cells and immunoblasts. In view of recent immunologic evidence that normal cytotoxic/suppressor T-cells selectively home to the gut surface epithelium, striking tumor cell epitheliotropism may be a morphologic marker for visceral lymphomas of cytotoxic/suppressor T-cell origin. This unique case broadens the clinical and morphologic spectrum of T-cell disorders.

Reversibility of lymphomas and lymphoproliferative lesions developing under cyclosporin-steroid therapy

Post-transplant lymphomas or other lymphoproliferative lesions, which were usually associated with Epstein-Barr virus infections, developed in 8, 4, 3, and 2 recipients, respectively, of cadaveric kidney, liver, heart, and heart-lung homografts. Reduction or discontinuance of immunosuppression caused regression of the lesions, often without subsequent rejection of the grafts. Chemotherapy and irradiation were not valuable. The findings may influence policies about treating other kinds of post-transplantation neoplasms.

Pseudolymphoma of colon

A case of pseudolymphoma of the colon is reported. Radiographically and endoscopically the lesion could not be conclusively distinguished from malignant neoplasm, particularly lymphoma or segmental colitis, thus necessitating right hemicolectomy. Careful histological examination established the diagnosis of pseudolymphoma with pathologic features identical to the focal form of pseudolymphoma more commonly observed in the stomach.

Aggressive large cell lymphoma of the ileum after long-term cyclophosphamide therapy for breast carcinoma

A middle-aged woman was treated for breast carcinoma with postoperative adjuvant chest wall irradiation, followed four and seven years later with therapy to spinal ports for palliation of metastatic disease. For the next three and a half years, she received oral cyclophosphamide on a daily basis to a total of more than 110 g. Twelve years after diagnosis and five years after the start of chemotherapy, an aggressive, large cell lymphoma of the ileum developed, with poor response to conventional therapy. This may represent the first patient with breast carcinoma in whom a treatment-induced non-Hodgkin's lymphoma has developed.

Localized lymphoid nodules of lung. A reappraisal of the lymphoma versus pseudolymphoma dilemma

Eleven patients with localized lymphoid nodules of the lung (LLN) were seen at the Mount Sinai Hospital from 1962-1981. The diagnosis of pseudolymphoma was made in six instances based on the following criteria: (1) solitary or multiple nodules discovered on chest roentgenograms composed of cytologically benign lymphoid cells (small lymphocytes); (2) polymorphic character of the infiltrate, including plasma cells, histiocytes and monocytes; and (3) presence of germinal centers in the lesion. Five lesions were classified as lymphomas and exhibited: (1) solitary or multiple nodules composed of atypical lymphoid cells; (2) absence of germinal centers; (3) lack of mediastinal lymph node involvement. Bronchial and/or pleural infiltration by lymphoid cells was present in lymphomas as well as in pseudolymphomas. Five lesions were studied with immunofluorescent techniques for the presence of intracytoplasmic immunoglobulins and in one pseudolymphoma, lymphocyte marker studies were performed. The procedures were not useful in separating benign from malignant lesions. All patients underwent surgery; three with lymphoma and one with pseudolymphoma received adjuvant chemotherapy. Patients were followed post surgically for up to 13 years. None of the six patients with pseudolymphoma died as a result of their lesions but two had either recurrences or developed extrapulmonary lymphoid lesions. All five lymphoma patients did well. Only one died while on chemotherapy with invasive pulmonary aspergillosis but no tumor. One-hundred and sixty-seven reported cases from the literature are analyzed. Pulmonary pseudolymphomas do not necessarily follow a benign course and malignant lymphomas limited to the lungs do not usually undergo progressive disease. Present pathologic criteria do not allow prediction of recurrence or progression of disease and are not acceptable for determining the advocacy of chemotherapy in patients with LLN.

Gastric pseudolymphoma. Its three subtypes and relation to lymphoma

Three separate histologic types of gastric pseudolymphoma (GPL) are described: (1) the common "inflammatory" type usually accompanied by ulceration and extensive fibrosis; (2) the entity known as "nodular lymphoid hyperplasia," which was associated with multiple intestinal lesions; and (3) the third reported case of angiofollicular lymphoid hyperplasia of the stomach (one with nodal involvement). Criteria for the common type were developed and, in general, confirm previous studies. However, the importance of evaluating nuclear cytology and mitotic rate are stressed. Organ infiltration by chronic lymphocytic leukemia should be excluded by the absence of an absolute peripheral lymphocytosis. In addition to the ten cases presented, the literature on 175 previous cases is summarized. GPL is estimated to account for 10-15% of all gastric lymphoid tumors. In comparison to gastric lymphoma, GPL is usually smaller in size and occurs a decade earlier on the average. Since an associated focal lymphoma was documented in an additional five cases, this study proposes that pseudolymphoma be considered a precursor lesion with malignant potential. Extensive pathologic sampling and total surgical excision are recommended.