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H Isomoto

Publications and source records attributed to H Isomoto.

At least 91 records · Page 5Linked to original sources
PubMed1991

[Lymphatic permeation of colorectal cancer--evaluation as a prognostic factor by prospective studies].

To evaluate lymphatic permeation as a prognostic factor in colorectal cancer, long-term prospective studies were conducted and the following results were obtained. 1) The degree of lymphatic permeation increased as the depth of invasion, lymph node metastasis, and stage advanced. 2) Moderate or marked lymphatic permeation (ly2 or ly3) was observed at a high rate in moderately and poorly differentiated adenocarcinoma. 3) Recurrence was more common in the patients with ly2 or ly3. 4) In stage 2 and 3 patients with slight plus no lymphatic permeation (ly0 or ly1), the seven-year survival rates were 89.8% and 85.6%, respectively. In the ly2 + ly3 group, the rates were 67.1% and 66.1%, respectively and a significant difference was noted. In stage 4, however, there was no significant difference between the two groups. Conclusions were as follows. 1) The degree of lymphatic permeation was considered to be extremely closely related to the progression of cancer, histological type and recurrence. 2) In stage 2 and stage 3, the degree of lymphatic permeation was an important prognostic factor, but in stage 4 it was not. 3) It was shown that lymphatic permeation as classified by the authors was a reliable index for survival rates.

Adenocarcinoma↗
PubMed1991

[Clinicopathological studies on perineural invasion of rectal cancer with special reference to the prognosis and nerve preserving operation].

Prospective studies on rectal cancer have been continued since 1982 in our department and in the present study, the significance of perineural invasion was investigated clinicopathologically in 432 cases of rectal cancer. (1) Perineural invasion in rectal cancer appeared to be closely related to the degree of progress of the cancer (depth of penetration, lymph node metastasis, liver metastasis and peritoneal dissemination), the degree of malignancy of the cancer (histologic type, lymphatic invasion and venous invasion) and the degree of inflammatory cell infiltration. (2) It was proven to be an important prognostic factor which influences recurrences and the survival rate. (3) If cases indicated for nerve preserving operation are considered to be those with no perineural invasion or with a low frequency of such invasion, it was assumed that such cases are those with well differentiated adenocarcinoma, a penetration depth of ss (a1) or less and no lymph node metastasis.

Humans↗
PubMed1991

[An experimental study of ethanol injection on VX2 liver cancer].

Ethanol injection therapy for rabbit VX2 cancer of the liver was performed to measure the extent of ethanol infiltration using normal hepatic tissue as control, to observe the serial histological findings after ethanol injection, and to determine the influence of the ethanol on survival days with VX2 cancer of the liver. The necrotic area caused by ethanol showed a significant dose-dependent correlation in the range of 0.1-1.0ml in the normal liver, and a significant correlation in the range of 0.2-1.0ml also in VX2 cancer of the liver. Further, VX2 cancer of the liver showed a significant extension in the number of survival days in the injection group after ethanol injection; 39.5 +/- 5.7 days in the injection group, against 29.3 +/- 2.9 days in the control group. In the successive observation of histological findings after injection, fibrosis started from the 3rd-5th day after ethanol injection and showed acceleration after the 7th day. Eosinophilic infiltration was seen in the VX2 cancer group but not among the controls. Since ethanol causes direct necrosis of the injected region, it is suggested that ethanol injection therapy is a potentially effective method of treating cancer of the liver.

Animals↗
PubMed1990

Treatment of rectal carcinoid tumors.

We investigated the treatment of 24 rectal carcinoid tumors from both the clinicopathologic and prognostic viewpoints. All tumors less than 2 cm in diameter had neither muscle layer invasion nor lymph node metastasis, except for an atypical carcinoid tumor that had both lymphatic permeation and intramural metastasis. One typical carcinoid tumor larger than 2 cm had both several lymphatic permeations and urinary bladder invasion. All cases had a good prognosis with no recurrence and no new metastases. For rectal carcinoid tumors less than 2 cm in diameter, local resection is sufficient, whereas radical operation is required for tumors larger than 2 cm in diameter. For atypical rectal carcinoid tumors, radical operation should be considered even if the diameter is less than 2 cm.

Adult↗
PubMed1990

Survival of rectal carcinoma patients studied with flow cytometric DNA analysis.

The cellular DNA content was measured with flow cytometry from paraffin-embedded materials in 197 patients with primary rectal cancer who had had "curative" resection. All patients were followed clinically for from 2.5 to 7 years. There was a significant difference in recurrent rate between DNA diploid and aneuploid tumors. The cumulative survival rate (Kaplan-Meier) of curative operative rectal carcinomas was worse in DNA aneuploid than in DNA diploid tumors (p less than 0.05). These data suggest that tumor DNA content is an important prognostic indicator for both recurrence and overall survival in patients with primary rectal carcinoma.

DNA, Neoplasm↗
PubMed1990

[Clinicopathologic study on venous invasion of colo-rectal cancer: a prospective study].

Metachronous liver metastasis developed less than in 5% of v0 and v1 groups, while it developed in 22% of v2 and v3 groups. In addition, it developed in 15% of EF(I) group, in 19% of EF group, in 10% of Intramural greater than Extramural group and in 16% of the Intramural less than or equal to Extramural group. Six-year survival rate of v0, v1, v2 and v3 groups in the cases of curative resection for advanced colo-rectal cancer were 97%, 85%, 57% and 51%, respectively. Also those of E, EF, EI(F), Intramural, Intramural greater than Extramural and Intramural less than or equal to Extramural groups were 83%, 65%, 55%, 86%, 80% and 55%, respectively. Non-hematogenous recurrence developed in 19.4% of v3 group, in 13.6% of EF(I) group and in 15% of Intramural less than or equal to Extramural group. Conclusions were as follows: (1) There was a close relationship between venous invasion and development of liver metastasis (or of non-hematogenous recurrence) and survival of patients. (2) It was proved that the diagnostic criteria of venous invasion established by the authors were good indices to predict survival of colo-rectal cancer patients.

Adult↗
PubMed1989

An index for estimating the probability of lymph node metastasis in rectal cancers. Lymph node metastasis and the histopathology of actively invasive regions of cancer.

We examined resected specimens from 40 cases of advanced rectal cancer to determine the extent of microtubular cancer nests and undifferentiated cancer cells (budding). We investigated the relationship between this budding and lymphatic invasion (ly), venous invasion (v), and lymph node metastasis (n), respectively. Moreover, we examined the relationship between ly, budding, and n in the preoperative biopsy specimens of 112 patients, including those of the 40 cases mentioned above. The degree of budding, which was abundant in the actively invasive region, showed a strong correlation with the degree of ly and the existence of n in the resected specimens. Also, budding was recognized in a relatively large portion of the biopsy specimens (52 of 112 [46.4%]) and lymph node metastasis was found in 41 of 52 specimens (78.8%). In 57 specimens, neither ly nor budding was found, and 16 of these specimens (28.1%) had positive lymph nodes. These results implied that the degree of budding in the actively invasive region can be a great help in predicting the presence of n. The presence or absence of budding in preoperative biopsy specimens also can be an important factor (along with the degree of differentiation and ly) in estimating the probability of n.

Adult↗
PubMed1989

Effect of OK-432 on large-bowel carcinogenesis in rats.

To examine the carcinogenetic and growth inhibitory effects of OK-432, large-bowel carcinoma was induced experimentally in rats by intrarectal injection of N-methyl-N-nitrosourea (MNU), and OK-432 was administered intradermally. Rats were sacrificed after six months and the large intestine was cut into serial sections. Histopathologic examination and analysis of the infiltrating mononuclear cells, using monoclonal antibodies, were performed. The average rate of carcinogenesis per rat was 15.7 +/- 8.5 in the MNU alone group (n = 10) and 8.3 +/- 3.5 in the MNU and OK-432 group (n = 6). The invasion was deeper than the muscularis propria in 16 out of 157 lesions (10.2 percent) in the MNU alone group and in one out of 50 lesions in the MNU + OK-432 group (2.0 percent) (P less than 0.05). When time of appearance of atypical glands or carcinomas were compared in the MNU alone and MNU + OK-432 group, carcinogenesis was found to be delayed in the MNU + OK-432 group. In the investigation of infiltrating mononuclear cells using monoclonal antibodies, there were increases in helper T cells in both the MNU alone and MNU + OK-432 groups, but there was little difference between the two groups. The results of this study suggest that the suppression of experimental carcinogenesis in the large bowel by the concomitant administration of OK-432 with MNU, may be due to the enhanced activation or prolonged activated state of immunocompetent cells, which appear via antigen recognition, by OK-432.

Adenocarcinoma↗
PubMed1989

Effects of gastrin releasing peptide and its related peptides on the release of gastrin.

Gastrin release of porcine gastrin releasing peptide (pGRP) and its related peptides were evaluated. The concentration of serum gastrin after intravenous administration of the peptides was measured by a radio immunoassay. Among pGRP and its related peptides, pGRP was found to retain full bombesin potency with respect gastrin release. The carboxy-terminal fragments of pGRP, 14-27, 18-27, and 19-27 were equipotent for gastrin release, though the peak value of serum gastrin caused by each of these three fragments was significantly less than that evoked by pGRP. The pGRP fragment 20-27, despite showing considerably lesser potency, still evoked statistically significant levels of serum gastrin during its infusion. On the other hand, pGRP fragments 21-27 and 1-13 did not exhibit any appreciable activity. It was concluded that the carboxy-terminal octapeptide 20-27 constitutes the vital active core for gastrin releasing activity of the pGRP molecule. The amino-terminal tridecapeptide pGRP (1-13), while itself inactive, appeared to be important for the full active of pGRP.

Amino Acid Sequence↗
PubMed1989

[Intra-arterial infusion chemotherapy of liver metastases in colorectal cancer].

We report the complications and the results of intra-arterial infusion chemotherapy (IAIC) for liver metastases in colorectal cancer. Fifteen synchronous liver metastases and 11 metachronous liver metastases were treated from September 1986 to February 1989. Eight cases had H1 (metastases in one lobe only), 11 cases H2 (a few scattered metastases in both lobes) and 7 cases had H3 (numerous metastases in both lobes). Eight cases underwent hepatic resection and 20 cases were treated by IAIC with implantable reservoir. Incidence of complication was decreased from 75% to 17% by the improved technique of hepatic arterial catheter intubation. Median survival was 12 months, 20 months and 8 months, respectively. When used with MMC, the IAIC showed unsatisfactory results. We should therefore investigate possible use of alternative drugs, their optimum dosages, and the regimens for improved chemotherapy.

Adult↗
PubMed1988

Evaluation of endorectal ultrasound for the assessment of wall invasion of rectal cancer. Report of a case.

To accurately assess the depth of cancer invasion, endorectal ultrasound was performed using a radial scanner (Aloka, 7.5 MHz) in 145 patients with rectal cancer. High-resolution ultrasound clearly depicted five- or seven-layer echographic structures in the normal rectal wall, and demonstrated cancer as a hypoechoic lesion. These layer structures provided an important feature in determining the depth of cancer invasion. Rectal cancers of 122 patients were examined thoroughly by endorectal ultrasound. In 95 of these patients (77.9 percent), ultrasonic assessment of the depth of cancer invasion as classified in four groups was correct, corresponding accurately to the microscopic findings. Ultrasonography overestimated the depth of cancer invasion in 21 patients, however, and underestimated it in six patients. This study indicated that a cause of the overestimation was inflammatory cell infiltration around cancer, and that one possible cause of underestimation was microscopically minimal invasion of cancer. Although there are certain limitations of endorectal ultrasound, this ultrasound technique will provide valuable information to determine the preoperative staging of rectal cancer.

Female↗
PubMed1987

Long term survival case of small (oat) cell carcinoma of the rectum.

A long term survival case of small (oat) cell carcinoma of the rectum in a 39-year-old female is presented. She complained of anal pain and occasional anal bleeding. The tumor was located at the anterior wall in the lower rectum. Biopsy specimens revealed a carcinoid tumor. She underwent trans-anal local resection for the first time in December, 1980. Macroscopic findings of the resected specimen showed a small nodule, 0.4 by 0.4 by 0.5 cm, with yellowish cut-surface. Microscopically, the tumor deeply invaded the submucosal layer. The appearances were indistinguishable from pulmonary small (oat) cell carcinoma. Since lymphatic permeations were moderately recognized in the tumor, she underwent radical operation (Miles' operation) with lymphadenectomy. Microscopic findings of the resected rectum revealed an intramural metastatic lesion with marked lymphatic permeations in the submucosal layer 2 cm distant from the primary lesion. Up to date, there is no evidence of local recurrence or liver metastasis. Small (oat) cell carcinoma of the rectum easily metastasizes lymphogenously through the lymph system from an early stage of the development. Wide surgical resection will be needed to give a long term survival even if the tumor is extremely small.

Adult↗
PubMed1987

Intraoperative ultrasonography in screening for liver metastases from colorectal cancer: comparative accuracy with traditional procedures.

As a new screening procedure, intraoperative ultrasonography using high-resolution real-time instruments was used routinely in 84 colorectal cancer operations to scan the entire liver for liver metastases. In 10 operations (11.9%), intraoperative ultrasonography identified 14 previously unrecognized metastatic tumors, all of which were less than 2 cm in size and were nonpalpable. The sensitivity of this technique in detecting metastatic liver lesions (97.8%) was significantly superior (p less than 0.01) to that of preoperative ultrasound (41.3%), computed tomography (47.8%), and surgical exploration (58.7%), while the specificity of each test was comparable (approximately 90%). High-resolution intraoperative ultrasonography is safe, simple to perform and more accurate than preoperative imaging and surgical exploratory methods. Therefore its use is encouraged during colorectal cancer surgery for screening of liver metastases.

Adult↗
PubMed1986

Detection of unrecognized liver metastases from colorectal cancers by routine use of operative ultrasonography.

The importance of diagnosis and detection of liver metastases cannot be overemphasized for the treatment and prognosis of colorectal cancers. As a new diagnostic technique, operative ultrasonography has been performed during 33 operations for colorectal cancers including three operations for metachronous liver metastases. Of these, in five patients (15.2 percent) ultrasonography using 5- or 7.5-MHz instruments identified metastatic tumors that had not been diagnosed during preoperative imaging studies or at exploration. Most of these tumors were approximately 1 cm in size and nonpalpable. Cases of these five patients are presented in this report. High-resolution operative ultrasonography is considered to be a valuable method for detection of unrecognized metastatic tumors and for precise localization and spatial assessment of these hepatic lesions. Because it is safe, simple, and highly sensitive, the routine use of operative ultrasound is encouraged during surgery upon colorectal cancers for systematic screening of metastatic liver tumors.

Adult↗