New device for MRI-guided surgical excision: report of a case.

A 37-year-old female was indicated to have a non-mass lesion in her left breast on ultrasonography (US) and visited our outpatient clinic. Mammography showed no findings of masses or microcalcification. Dynamic magnetic resonance imaging (MRI) showed a segmental enhanced lesion consisting of nodular and ring enhancement. A US-assisted vacuumed needle biopsy was performed, and the histological findings revealed sclerosing adenosis and apocrine metaplasia. After 1 year of follow-up, the MRI findings suggested both a benign lesion and ductal carcinoma in situ, and surgical excision was performed. We used a new device to evaluate the surgical margin on MRI. The non-mass lesion was excised according to the device-guided margin under local anesthesia. The histological findings revealed the features of mastopathy. Following excision, MRI showed no residual non-mass lesions, and the shape of the patient's left breast was maintained.

Progressive transformation of the germinal center of extranodal organs: a clinicopathological, immunohistochemical, and genotypic study of 14 cases.

Progressive transformation of germinal center (PTGC) usually affects the peripheral lymph nodes. Little is known about the extranodal PTGC. To clarify the clinicopathological and molecular findings of extranodal PTGC, we studied 14 such cases. Using formalin-fixed, paraffin-embedded sections, we carried out histological and immunohistochemical examinations, as well as in situ hybridization (ISH) and polymerase chain reaction (PCR). Eleven patients were female, and three were male. They were between 44 and 77 years old, with a mean age of 62 years. The large intestine (n=7) was the most frequently involved tissue, followed by skin (n=2) and subcutaneous soft tissue (n=2). Oral cavity, Waldeyer ring, and orbit were affected in one case each. Histologically, 13 cases contained both early stage PTGC and late stage PTGC. The remaining 14th case contained only late stage PTGC. Expansion of the marginal zone was identified in three cases. Immunohistochemical study demonstrated the reactive nature of the B-cells in all 14 lesions. However, PCR study revealed immunoglobulin heavy chain (IgH) gene rearrangement in one of our 14 cases. There was no development of B-cell lymphoma in one lesion with IgH rearrangement. ISH study demonstrated Epstein-Barr virus-encoded small RNA+ cells in three lesions. Compared with PTGC of the peripheral lymph node, PTGC of extranodal sites was characterized by a female predominance, an older age group, and the presence of numerous PTGC at the affected sites. However, the histological findings of extranodal PTG were similar to those of lymph node PTGC. The clinicopathological findings of the extranodal PTGCs appeared to be different from those of lymph node PTGC.

Histological variety of localized lymphoid hyperplasia of the large intestine: histopathological, immunohistochemical and genotypic findings of 16 cases.

Previous reports emphasized that localized lymphoid hyperplasia (LLH) of the large intestine is usually histologically characterized by large lymphoid follicles with striking enlarged germinal centers, and a narrow surrounding mantle zone and marginal zone (MZ). To clarify the histological varieties of LLH of the large intestine, 16 such cases have been studied. The present study demonstrated histological diversity of the LLH of the large intestine including (i) reactive follicular hyperplasia (RFH) (n=8), (ii) RFH with progressive transformation of the germinal center (PTGC) (n=3), (iii) RFH with MZ hyperplasia (n=3) and (iv) RFH with PTGC and MZ hyperplasia (n=2). Overall histomorphological findings of the present series appear quite different from previous descriptions of LLH of the large intestine. The present study showed histological variety of the LLH of the large intestine. Moreover, LLH of the large intestine should be differentiated from extranodal marginal zone B-cell lymphoma and nodular lymphocyte predominant Hodgkin lymphoma as well as follicular lymphoma. Immunohistological studies demonstrated the reactive nature of all 16 lesions. However, three cases showing RFH demonstrated immunoglobulin heavy chain gene rearrangement by polymerase chain reaction study in 12 cases examined. It remains unclear whether these three cases showing RFH could be a sign of the prelymphomatous stage (incipient follicular lymphoma) or representing merely an exaggeration of normal B-cell clonal response in the germinal centers.

Localized lymphoid hyperplasia of the rectum representing progressive transformation of the germinal center. A report of two cases.

Histologically, benign lymphoid hyperplasia (BLH) of the rectum is usually characterized by large lymphoid follicles with active germinal centers, and a narrow surrounding mantle zone and marginal zone. We present two cases of BLH of the rectum demonstrating progressive transformation of the germinal center (PTGC). The patients were 50- and 71-year-old Japanese women. Colonoscopy demonstrated small sessile polyps in both cases. The resected specimen contained numerous lymphoid follicles with active germinal centers and a portion of the lymphoid follicles exhibited PTGC. The area showing PTGC contained a few large lymphoid cells resembling lymphocytic and histiocytic Reed-Sternberg cells of nodular lymphocyte-predominant Hodgkin lymphoma. These PTGC contained small- to-medium clusters of epithelioid cells in both cases. In situ hybridization studies demonstrated scattered Epstein-Barr virus (EBV)-encoded small RNA-positive medium and large lymphoid cells and crypt epithelium in both lesions. EBV may be involved in the etiology of a subset of BLH of the rectum. However, reactivity of lymphoid cells for EBV has been reported in lymphoid tissues in a high percentage of "normal" individuals. The etiology of BLH of the rectum remains unclear.

Progressive transformation of germinal centers: a clinicopathological study of 42 Japanese patients.

To clarify the clinicopathological features of progressive transformation of germinal center (PTGC) unrelated to nodular lymphocyte predominant Hodgkin's lymphoma in Japanese patients, we reviewed 42 cases and compared the results with those of the United States and Germany. Our results were similar to theirs, with male predominance (M/F ratio, 3:1) and the presentation of a solitary asymptomatic enlarged lymph node in the head and neck area as the common features. However, in Japan, PTGC occurs more frequently in elderly patients. In this study, 12 (29%) of the patients with PTGC were aged 60 years or more. Thirteen patients (31%) with lymphadenopathy in the neck and head area had developed localized chronic inflammation (chronic sialoadenitis=4, chronic tonsillitis=3, infectious epidermal cyst=2) or an autoimmune disorder (hyperthyroidism=2 and bronchial asthma=2). None of the patients developed a malignant lymphoma during the follow-up period of 5 to 238 months (median 27 months). Histologically, in a single longitudinal section of the lymph node, the PTGC occupied up to 5% of the total follicles in 22 patients, 5-10% in 10, 10-20% in 7, and more than 20% in 3. In 5 (12%) patients, an association with prominent marginal zone hyperplasia was also noted. This study also indicates that nodal involvement by various low-grade B-cell lymphomas exhibiting marginal zone distribution patterns should be considered as a differential diagnosis of PTGC. Moreover, in Japan, PTGC is thought to be involved in the etiology of florid reactive follicular hyperplasia in elderly patients.