Tomohiko Aihara

The detection of breast carcinoma micrometastases in axillary lymph nodes by means of reverse transcriptase‐polymerase chain reaction

Background. The development of a sensitive method for the detection of breast carcinoma micrometastases in axillary lymph nodes is reported.

Fibroadenoma and Phyllodes Tumor

Background. The histogeneses of fibroadenoma and phyllodes tumor of the breast appear to be closely related, but it is still unclear whether fibroadenoma can progress directly to phyllodes tumor.

Detection of Gastric Cancer Micrometastases in Lymph Nodes by Amplification of Keratin 19 mRNA with Reverse Transcriptase‐Polymerase Chain Reaction

A sensitive method for the detection of gastric cancer micrometastases in lymph nodes was developed. The method was based on amplification of keratin 19 mRNA by reverse transcriptase‐polymerase chain reaction (RT‐PCR). Keratin 19 RT‐PCR showed that keratin 19 mRNA was expressed in all 12 gastric cancers, but not in any of 20 normal control lymph nodes, indicating that keratin 19 mRNA is a good target of RT‐PCR for the detection of gastric cancer micrometastases in lymph nodes. Serial dilution studies of RNA extracted from gastric cancers against RNA extracted from control lymph nodes demonstrated that the detection sensitivity of the keratin 19 RT‐PCR method was one cancer cell in 103‐105 lymph node cells. Detectability of lymph node metastases was compared between keratin 19 RT‐PCR and conventional histological examination, using 100 lymph nodes obtained from 12 gastric cancer patients. Keratin 19 mRNA was detected in all of the seven lymph nodes which were historically metastasis‐positive. Of the 93 lymph nodes which were histologically metastasisnegative, 79 were found not to express keratin 19 mRNA but 14 were found to express keratin 19 mRNA, indicating that these lymph nodes contained micrometastases which could not be detected by histological examination. These results demonstrate that keratin 19 RT‐PCR is a more sensitive method than histological examination for the detection of gastric micrometastases in lymph nodes.

Clonal Analysis of Regenerative Nodules in Hepatitis C Virus- Induced Liver Cirrhosis

BACKGROUND/AIMS Based on histological criteria, regenerative nodules in cirrhotic liver have been generally considered to result from hyperplastic proliferation of hepatocytes. Whether these nodules are hyperplastic or neoplastic has not been determined definitively. This study examined the issue by clonal analysis of each nodule. METHODS The method for clonal analysis was based on restriction fragment length polymorphism of the X chromosome-linked phosphoglycerokinase gene and on random inactivation of the gene by methylation. RESULTS Clonality of hepatocellular carcinoma (n = 7) and regenerative nodules (n = 76) induced by hepatitis C virus infection was analyzed. All carcinomas were monoclonal. Clonal analysis of regenerative nodules showed that 43% (33 of 76) were monoclonal in origin. Adjacent monoclonal nodules showed inactivation of the same allele of phosphoglycerokinase gene. Because the gene allele is inactivated at random, it is unlikely that each nodule happens to inactivate the same allele; it is more likely that monoclonal cell expansion is initiated before the nodule is established by septum formation. CONCLUSIONS Monoclonal cell expansion is seen in a considerable number of regenerative nodules in cirrhotic liver. The results indicate that certain genetic changes, which are required for hepatocarcinogenesis, have already occurred in these nodules.

Mammaglobin B as a novel marker for detection of breast cancer micrometastases in axillary lymph nodes by reverse transcription‐polymerase chain reaction

A novel reverse transcription‐polymerase chain reaction (RT‐PCR) assay using mammaglobin B gene was developed for detection of breast cancer micrometastases in axillary lymph nodes. Fourteen primary breast cancers and 56 axillary lymph nodes from six patients with primary breast cancer and 15 control lymph nodes from non‐cancer bearing patients were subjected to this assay. The transcript of mammaglobin B gene was detected in none of the control lymph nodes, but in all of the 14 primary breast cancers. Eleven out of the 56 lymph nodes from the patients, which were shown to be positive by histological examination, were also proven positive by this assay. On the other hand, fourteen of the 45 (31%) histologically negative lymph nodes were also shown to express mammaglobin B mRNA, which suggested the presence of micrometastases in these lymph nodes. RT‐PCR using mammaglobin B gene could therefore be a useful tool for detection of micrometastases of breast cancer.

Comparison of frozen section and touch imprint cytology for evaluation of sentinel lymph node metastasis in breast cancer

Background: Sentinel lymph node metastasis of breast cancer is evaluated by frozen section (FS) or touch imprint cytology (TIC). However, which of the two methods is superior remains controversial. Here we directly compared the sensitivity of these methods prospectively.Methods: The study included 208 SNs harvested from 107 consecutive patients with breast cancer who underwent sentinel lymph node biopsy. SNs were serially sectioned at 2-mm intervals, and two sections were subjected to intraoperative evaluation of FS with hematoxylin and eosin staining. TIC specimens were prepared from all cut surfaces and analyzed by Papanicolaou (TIC) and cytokeratin (TIC with immunohistochemistry; TIHC) immunohistochemistry.Results: Thirty-five SNs from 27 patients were positive by final histopathology. The sensitivity per sentinel lymph node of FS was 89%; it was 86% for TIC and 89% for TIHC. Among 173 negative SNs, the results of FS were concordant with final histopathology, but TIC and TIHC were positive in 1 and 5 histopathology-negative SNs, respectively. The sensitivity per patient of FS was 85%; it was 85% for TIC and 89% for TIHC. Among 80 patients with node-negative disease, the results of FS and TIC were concordant with final histopathology, whereas TIHC was positive in 3 patients (3.8% were upstaged). A slight improvement of sensitivity per patient was achieved by the combination of FS and TIC (to 89%) or FS and TIHC (to 93%).Conclusions: The sensitivity of FS was almost equivalent to that of TIC. TIHC had a better sensitivity than FS and TIC, but it upstaged a few node-negative patients.Background: Sentinel lymph node metastasis of breast cancer is evaluated by frozen section (FS) or touch imprint cytology (TIC). However, which of the two methods is superior remains controversial. Here we directly compared the sensitivity of these methods prospectively. Methods: The study included 208 SNs harvested from 107 consecutive patients with breast cancer who underwent sentinel lymph node biopsy. SNs were serially sectioned at 2-mm intervals, and two sections were subjected to intraoperative evaluation of FS with hematoxylin and eosin staining. TIC specimens were prepared from all cut surfaces and analyzed by Papanicolaou (TIC) and cytokeratin (TIC with immunohistochemistry; TIHC) immunohistochemistry. Results: Thirty-five SNs from 27 patients were positive by final histopathology. The sensitivity per sentinel lymph node of FS was 89%; it was 86% for TIC and 89% for TIHC. Among 173 negative SNs, the results of FS were concordant with final histopathology, but TIC and TIHC were positive in 1 and 5 histopathology-negative SNs, respectively. The sensitivity per patient of FS was 85%; it was 85% for TIC and 89% for TIHC. Among 80 patients with node-negative disease, the results of FS and TIC were concordant with final histopathology, whereas TIHC was positive in 3 patients (3.8% were upstaged). A slight improvement of sensitivity per patient was achieved by the combination of FS and TIC (to 89%) or FS and TIHC (to 93%). Conclusions: The sensitivity of FS was almost equivalent to that of TIC. TIHC had a better sensitivity than FS and TIC, but it upstaged a few node-negative patients.

Histologic characteristics of breast cancers with occult lymph node metastases detected by keratin 19 mRNA reverse transcriptase‐polymerase chain reaction

Amplification of keratin 19 mRNA (K19) by reverse transcriptase‐polymerase chain reaction (RT‐PCR) has been shown to be a sensitive method to detect occult breast cancer metastases in lymph nodes.

Detection of pancreatic and gastric cancer cells in peripheral and portal blood by amplification of keratin 19 mRNA with reverse transcriptase-polymerase chain reaction

Reverse transcriptase‐polymerase chain reaction (RT‐PCR) targeted at keratin 19 mRNA was applied to detect circulating cancer cells in the peripheral and portal blood of pancreatic and gastric cancer patients. Keratin 19 mRNA expression was studied by RT‐PCR in cancer tissues (12 pancreatic and 15 gastric cancers) and in peripheral and/or portal blood samples from patients with pancreatic cancer (stage I, n = 5; stage II, n = 1; stage III, n = 15; stage IV, n = 19), gastric cancer (stage Ia,b, n = 28; stage II, n = 9; stage IIIa,b, n = 5; stage IVa,b, n = 7) and benign pancreatic diseases (n = 7). Peripheral blood samples from 50 healthy volunteers served as controls. RT‐PCR was conducted in duplicate in each sample, and only samples showing keratin 19 transcript in both determinations were considered as being positive. All the pancreatic and gastric cancers, but none of the control blood samples, were found to be positive. Dilution study using pancreatic cancer cells serially mixed against peripheral blood showed that detection sensitivity was more than one cancer cell in 106 peripheral blood mononuclear cells. In pancreatic cancer patients, RT‐PCR analysis of the portal blood samples gave positive results in one stage III and one stage IV patient, and that of peripheral blood samples gave positive results in 2 stage IV patients. No positive results were obtained in any of the blood samples from gastric cancer patients. Our results indicate that incidence of circulating cancer cells is unexpectedly very low even in advanced pancreatic and gastric cancer patients. Int. J. Cancer 72:408–411, 1997.

Mammaglobin B gene as a novel marker for lymph node micrometastasis in patients with abdominal cancers.

Mammaglobin B is a recently-isolated gene speculated to belong to the uteroglobin gene family and is overexpressed in primary breast cancers. We investigated mammaglobin B mRNA expression in various cancers of the digestive system. Given the absence of mammaglobin B expression in normal lymph nodes, we also assessed the usefulness of mammaglobin B as a marker for lymph node micrometastases in cancer patients. Mammaglobin B gene transcripts were frequently detected by reverse transcriptase-polymerase chain reaction (RT-PCR) assay in primary tumors of the esophagus (2/3), stomach (7/7), colon (15/15), pancreas (4/6), common bile duct (6/6), cholangioma (2/2) and gall bladder (1/1). Mammaglobin B overexpression was observed in three of 15 cases (20%) of colon cancer, suggesting its possible contribution to colon carcinogenesis. Down-regulated mammaglobin B expression was observed in hepatoma cells in comparison with corresponding non-cancerous livers (3/3). RT-PCR assay of mammaglobin B detected 14 of 15 histologically positive lymph nodes from patients with gastric cancer, colon cancer and cholangioma. Seven of 32 (22%), three of nine (33%), and three of seven (43%) histologically negative nodes from patients with gastric, colon and cholangiocellular carcinoma, respectively, were found to express mammaglobin B mRNA. Our results showed that expression of mammaglobin B was frequently detected in cancers originating in digestive organs, especially adenocarcinomas, and that mammaglobin B gene detected by RT-PCR may be a potentially useful molecular marker for lymph node micrometastases of various digestive organ cancers.

Phase II Study of Weekly Paclitaxel for Docetaxel-Resistant Metastatic Breast Cancer in Japan

Abstract:  The purpose of the study was to evaluate the efficacy of weekly paclitaxel (PTX) against metastatic breast cancer (MBC) that was resistant to docetaxel (DTX) given every 3 weeks. A multicenter phase II study was performed. Women with MBC resistant to DTX were eligible for enrollment. DTX resistance was defined as no tumor response to DTX and stable disease, partial response, or complete response to DTX preceding disease progression. PTX 80 mg/m2 was administered over 1 hour once a week for 3 weeks per 4‐week cycle. Among 47 enrolled patients, 46 patients were assessable for response and toxicity. The overall objective response rate (complete responses [CRs] and partial responses [PRs]) was 17.4% and overall clinical benefit rate (CRs, PRs, and stable disease ≥24 weeks) was 26.1%. The median time to progression was 11 weeks. There were a few severe hematologic toxicities related to the therapy, with grade 4 neutropenia (4.3%) and thrombocytopenia (2.2%). Grade 3 anaphylaxis and grade 3 neuropathy were observed in one patient (2.2%) each. The median delivered dose intensity was 77.6 mg/m2/week, 97.1% of the planned dose intensity. Weekly PTX has activity in patients with MBC resistant to DTX every 3 weeks.