Primary lymphomas of the gastrointestinal tract. A clinicopathologic study of 60 cases

Classification of primary gastric lymphomas according to histologic features

Histologic features of low-grade gastric lymphomas of mucosa-associated lymphoid tissue (MALT) have been extensively described, and transformation to a large cell (high-grade) lymphoma can occur. We characterize high-grade gastric lymphoma histologically in an attempt to distinguish between MALT-type and non-MALT-type lesions. We studied a series of 60 gastric lymphomas and characterized them clinically, histopathologically, and immunophenotypically. Low-grade gastric lymphomas were classified according to established criteria. High-grade lymphomas were classified in three groups based on the presence or absence of a low-grade component and lymphoepithelial lesions (LELs): 1) high-grade MALT lymphomas appearing in low-grade MALT lymphomas (LG/HG MALT lymphoma); 2) large cell lymphoma with LELs composed of large cells (high-grade LELs) but without a low-grade component (HG MALT lymphoma); and 3) diffuse large cell lymphoma without a low-grade MALT lymphoma component or LELs (DLCL). Twenty-two lymphomas were classified as low-grade MALT lymphomas, 16 as LG/HG MALT lymphomas, 10 as HG MALT lymphomas, and 12 as DLCL. B-cell immunophenotype was confirmed in all 55 cases in which immunophenotyping was performed. Low-grade LELs were seen in all low-grade MALT lymphomas, and CD20(L26) expression confirmed B-cell phenotype in the LELs in 20 of 20 cases. Clinical follow-up was available for 56 patients (range, 1-264 months; mean, 57 months). Actuarial analysis of disease-specific survival and relapse-free survival showed that clinical stage was highly statistically significant (P < 0.0001), whereas histologic type and grade approached statistical significance. Multivariate analysis showed that clinical stage was the only significant factor in relapse-free and disease-specific survival.

Primary gastric lymphomas: a clinicopathologic study with literature review

Prognostic factors and treatment results were analysed in 28 consecutive patients with primary gastric lymphoma (PGL) diagnosed and treated, all by surgery and in many cases with additional chemotherapy (CT) and/or radiotherapy (RT), between 1977 and 1988. There were 13 patients in stage IE, 5 in IIE, and 10 in stage IV. The resection rate was 96.4% (27/28). Sixteen patients underwent an extended total and 11 a subtotal gastrectomy. Seventeen out of 25 cases (68%) were diagnosed by endoscopic biopsies. In 10 endoscopically diagnosed PGL cases the clinical staging and separation between stages IE and IIE from stage IV, due to ultrasonographic scan, computed tomography and bone marrow biopsy, was correct and the same with the surgical-pathological staging information. According to the Kiel-classification 18 patients had a low-grade and 9 patients a high-grade lymphoma. One patient could not be classified. All patients were completely followed-up, in an average time of 52 months. The probability of overall 5-year survival was 92% in stage IE, 75% in stage IIE, 88% in stages IE+IIE together, and 35% in stage IV. Extent of surgery (total vs. subtotal gastrectomy), Kiel-classification (low-grade vs. high-grade malignant histologic subtypes) and adjuvant CT in patients with stage IE (all 11 patients without CT remain in complete remission after an average of 45 months) did not significantly influence survival. The sole prognostic factor with proven impact on survival was the stage of disease (IE+IIE vs. IV: P = 0.001). For the Kiel-classification in particular there was no significant difference between low-grade and high-grade lymphomas with regard to the sex, symptomatic, extent of surgery, and stage at operation. These findings, together with data from the literature, suggest that gastric resection seems to be the optimal primary treatment in clinically assessed stages IE or IIE. In patients with stage IE disease, surgical resection can result in a cure, with no need for further therapy. The CT and/or RT can be effective in unresected and even bulky cases. Because of the difference in primary treatment, a preoperative clinical staging and separation between early stages from stage IV is always indicated.

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.

Gastrointestinal malignant lymphomas of the mucosa-associated lymphoid tissue: factors relevant to prognosis

Three hundred seven cases (244 gastric, 63 intestinal) of primary gastrointestinal non-Hodgkin's lymphoma (NHL) in stages EI and EII, according to a modified Ann Arbor system, were examined retrospectively. The histological classification for mucosa-associated lymphoid tissue-derived lymphomas was applied. Gastric NHLs (male-female ratio, 0.97; mean age, 64.5 years) were stage EI in 51% and stage EII in 49% of cases. Histological grade of malignancy was low in 41% and high in 59% of cases; all NHLs were B-cell type. Tumors were radically resected in 87%, and overall 2-, 5-, and 10-year survival rates were 61%, 55%, and 46%, respectively. Early lymphomas (substage EI1) had best prognosis (5- and 10-year survival rates, 90% and 70%, respectively). Intestinal NHLs (male-female ratio, 1.1; mean age, 54.4 years) were stage EI in 30% and stage EII in 70% of cases. Histology was low grade in 21% and high grade in 79%, and all but 11 cases were B-cell type. In 58% of cases, radical tumor resection resulted in overall 2- and 5-year survival rates of 44% and 24%, respectively. Major prognosticators for survival in gastric location were low-grade histology, low depth of infiltration, and low stage and radical resectability of lymphoma; all factors were strictly intercorrelated. In intestinal site, radical tumor resectability was highly significant for survival. Cumulative proportion of relapses after 5 years was higher in intestinal than in gastric sites (44% vs. 22%). In conclusion, primary gastrointestinal tract NHLs may represent an entity with respect to characteristic histological features, focal tumor growth, and potential cure by radical resection. Because of late relapses, clinical follow-up is needed.

Primary B-cell gastric lymphoma: a clinicopathological study of 145 patients

Resection specimens from 145 patients with primary B-cell gastric lymphoma at stage IE (n = 88) and at stage IIE (n = 57) were investigated. Histologically, low-grade malignant B-cell lymphomas arising from the mucosa-associated lymphoid tissue, including immunocytoma (n = 71), could be distinguished from high-grade malignant B-cell lymphomas with (n = 25) and without (n = 49) evidence of a low-grade component. The very rare low-grade B-cell lymphomas of centroblastic-centrocytic, centrocytic, and plasmacytic type were not considered. All patients had undergone primary gastric resection, and 65 received additional chemotherapy (n = 33), radiotherapy (n = 22), or both (n = 10). Actuarial overall survival rates calculated by the Kaplan-Meier life-table method were 76% after 5 years and 58% after 10 years. According to the Mantel test and a multivariate analysis using the Cox regression method, patients at stage IE had a significantly better survival probability than those at stage IIE (P less than 0.0001); 5-year survival rates were 87% and 61%, respectively. The survival probability for low-grade malignant lymphomas was significantly better than for tumors with secondary high-grade transformation (P less than 0.05) or for primary high-grade lymphomas (P less than 0.0001), whereas the two high-grade groups were not significantly different. Five-year survival rates were 91% for low-grade, 73% for secondary high-grade, and 56% for primary high-grade malignant lymphomas. Retrospectively, no significantly different survival rates were found between patients who had undergone gastric resection alone and patients who had received additional treatment. However, survival analyses showed that classification and grading according to the histopathological concept of mucosa-associated lymphoid tissue-derived gastric lymphomas into low-grade B-cell lymphomas of mucosa-associated lymphoid tissue type and high-grade B-cell lymphomas with or without evidence of a low-grade component has great prognostic relevance.

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 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.

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.

Primary gastric non-Hodgkin's lymphomas in Japan

A pathological study was carried out on 124 cases of primary gastric non-Hodgkin's lymphoma (NHL) in Japan. Macroscopically the cases were divided into three groups; flat, polypoid, and ulcerative types. Early lymphomas were distinguished from advanced by the depth of infiltration. Histologically the commonest type was ML, immunoblastic (ML, ibl.). Most were high grade malignancy, in terms of morphology. Lymph node involvement was found in 44 cases. Correlation between macroscopical appearance, histological diagnosis, stage and accompanying reactive lymphoid hyperplasia (RLH) was studied. Three main prototypes of gastric NHL were noted: The first was macroscopically ulcerative type, histologically high grade malignancy and lacked RLH; the second was mostly flat, ML, lymphoplasmacytic/lymphoplasmacytoid (ML, l-p.) or ML, ibl., associated with RLH, and arose from neoplastic proliferation of the interfollicular lymphoid cell in RLH (termed gastric NHL of interfollicular type); the third was mostly flat, ML, centroblastic (ML, cbl.) or lymphoblastic (ML, lbl.), associated with RLH, and originated from neoplastic proliferation of the follicular center cell in RLH (gastric NHL of follicular type).

Primary gastric lymphoma--a tumour of mucosa-associated lymphoid tissue. A histological and immunohistochemical study of 36 cases

A series of 36 cases of non-Hodgkin's lymphoma of the stomach have been analysed using routine histological techniques and immunohistochemistry. All cases were categorized as follicle centre cell lymphomas. Apart from two cases who had nodal lymphomas followed by gastric lymphomas, all cases appeared to represent primary lymphoma of mucosa-associated lymphoid tissue. It is proposed that the morphology and behaviour of these tumours reflect their origin from gut-associated lymphoid tissue. Physiologically well-differentiated examples show monotypic plasmacytic differentiation. Infiltration of gastric glands by follicle centre cells forming characteristic lympho-epithelial lesions is, we believe, a pathognomonic feature of primary gastric lymphoma. The spread of these tumours is within the mucosa-associated lymphoid tissues involving, in particular, the nasopharynx and lung but seldom spreading to peripheral lymph nodes or bone marrow. This concept of gastric lymphomas as primary neoplasms of gut-associated lymphoid tissue has important implications with respect to the investigation and treatment of this disease.