Search PubMed⌕ Search

Biomedical subjects

K Sako

Publications and source records attributed to K Sako.

At least 91 records · Page 5Linked to original sources

Early oral and oropharyngeal cancer in nontobacco users.

In order to define the clinical behavior and characteristics of oral and oropharyngeal squamous cancer in nontobacco users, 40 surgically treated American Joint Commission (AJC) stage I and II tumors in 36 nontobacco-using patients were retrosepctively compared with 306 similarly staged and treated tumors in 286 tobacco-using patients. Significantly more nontobacco-associated tumors were found in females (P less than 0.005) whose mean age was significantly greater than that of tobacco users (P less than 0.001). Nontobacco users had proportionately more tumors of the buccal mucosa, oral tongue, and hard palate and fewer of the floor of mouth (P less than .025). There was no difference in the distribution of histologic grades between the two groups. The incidence of initial or subsequent nodal disease and the incidence of second upper aerodigestive tract cancers were similar. Despite similar rates of failure of initial treatment, the mean time to failure was significantly greater in nontobacco users (P less than 0.01). There was no difference in determinate 5-year survival between the two groups. Oral and oropharyngeal cancers in nontobacco users are no more aggressive than similar lesions in tobacco users.

Age Factors↗

Skin cancer of the nose: options for reconstruction.

The nose is the most common site of skin cancer on the human body. This review was compiled to enumerate the many reconstructive techniques which are available and to discuss the advantages and disadvantages of each technique. Five hundred twenty-one patients with nasal cancer were treated at Roswell Park Memorial Institute from 1964 to 1981. Four hundred five patients were treated by cryotherapy, electrocautery, chemosurgery, radiation therapy, or local excision with primary closure. Forty-six patients were treated with simple nasolabial flaps. The remaining 70 patients underwent more extensive resections and reconstructions. Their records were reviewed. At 5 years the local recurrence rate was 3% for basal cell carcinoma and 20% for squamous cell carcinoma. The multiple reconstructive techniques which were utilized in these patients are discussed. Skin-grafting procedures were used to manage 51% of the patients. Prostheses were used in 9%. Multiple different reconstructive flaps were used for the remaining 40% of the patients. The management of large nasal carcinomas must be individualized with therapeutic decisions being made by a practitioner who is familiar with the many reconstructive options. This will ensure the optimal functional and aesthetic result for each patient.

Adult↗

Suppressive therapy of thyroid nodules in patients with previous radiotherapy to the head and neck.

This is a prospective, randomized study of 431 patients with palpable thyroid nodules who had previous radiotherapy for benign disorders of the head and neck area to determine the response of the thyroid nodules to suppressive therapy and the incidence of thyroid cancer in patients who could not be suppressed and had surgery. A complete response was achieved within 6 months in 18.3 percent of the patients, and in an additional 26 percent of patients between 7 and 12 months postoperatively. Twenty percent of the patients showed complete disappearance of nodules after 1 to 2 years of suppressive therapy. Twenty-two percent who underwent surgery showed carcinoma. If suppressive therapy is to be used, a trial of 1 year rather than 3 or 6 months, as often recommended, may be appropriate.

Adult↗

[Somatosensory evoked potential and local cerebral glucose utilization in the transient MCA-occluded rat].

Wistar rats were used through the experiments. Preparatory operations for the autoradiography and somatosensory evoked potential (SEP) were performed under 1.5% halothane anesthesia. After a control measurement of SEP, the left MCA was occluded with a micro clip. The animals were divided into 2 groups. In the 1st group (n = 8), the clip was removed 1 hour after MCA occlusion and 4 rats were used for the measurement of local cerebral glucose utilization (LCGU) by 14C-DG autoradiography. Another 4 rats were allowed to recover from anesthesia and used for the histopathological examination after 72 hours. In the 2nd group (n = 8), the clip was removed 2 hours after occlusion and the same procedures were performed. SEP was monitored throughout the experiment. Two positive and one negative peaks were recorded before MCA occlusion. SEP diminished immediately after MCA occlusion. Following the removal of the clip, complete recovery of SEP was observed in the 1st group of rats. However, in the 2nd group, recovery of SEP was minimal. In the 1st group, LCGU in the sensorimotor cortex at 30 minutes after reperfusion showed 22% reduction compared to that of the contralateral homologous area. In the 2nd group, in the contrast, 66% reduction of LCGU was observed. Experimental results indicate that SEP and LCGU in the early recovery period of ischemia are able to predict the reversibility of ischemic brain.

Animals↗

Metastatic patterns in squamous cell cancer of the head and neck.

This retrospective study on 832 head and neck cancer patients who died between 1961 and 1985 was carried out to determine the incidence and sites of distant metastases. All patients were staged prior to definitive treatment and were autopsied. The overall incidence of distant metastases was 47 percent. The hypopharynx had the highest incidence of distant metastases (60 percent), followed by the base of the tongue (53 percent) and the anterior tongue (50 percent). Of the 387 patients with distant metastases, 91 percent died with uncontrolled tumor either at the primary site or in the neck. The lung was the most common site of distant metastases (80 percent), followed by the mediastinal nodes (34 percent), the liver (31 percent), and bone (31 percent). Overall, 6 percent of the patients had stage I disease, 20 percent had stage II disease, 32 percent had stage III disease, and 43 percent had stage IV disease. The highest incidence of distant metastases was found in those patients with stage IV disease (193 of 350 patients, 55 percent). We believe that the initial stage of disease does appear to be related to the ultimate development of the distant metastases.

Carcinoma, Squamous Cell↗

[The effects of hyperglycemia on ischemic brain edema].

The effects of hyperglycemia on ischemic brain edema in rats were studied by measuring the local changes in water content of brain and cerebrovascular permeability using a transient middle cerebral artery (MCA) occlusion model. Rats, fasted except for water for 12-16 hours, were used. They were anesthetized with halothane and the stem of the left MCA was occluded for 2 hours by a microclip. Reperfusion was performed by removal of the clip. The rats were allowed to awake from anesthesia after removal of the clip. Hyperglycemia was induced by intraperitoneal injection of 50% glucose and same volume of physiological saline was injected intraperitoneally 20 minutes before MCA occlusion in control rats. Cerebrovascular permeability was measured by quantitative autoradiography using 14C-alpha-amino-isobutyric acid (14C-AIB) 2 hours after reperfusion. The specific gravity of cerebral tissue, determined by the gradient column with bromobenzene and kerosene, was used to study local changes in brain water content 2 hours after MCA occlusion and 2 hours after reperfusion. In hyperglycemic rats, plasma glucose content-ration rose to over 500 mg/dl at the peak and then declined. A hyperglycemic state around 300 mg/dl was maintained during the experiments. Elevation of hematocrit and plasma osmolarity were observed in hyperglycemic rats. At 2 hours after MCA occlusion, specific gravity of the brain was decreased in the left MCA territory, especially in the frontal cortex, in both groups. The decrease in the frontal cortex in hyperglycemic rats was statistically significant compared with that in the control rats.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Major head and neck reconstruction using the deltopectoral flap. A 20 year experience.

Six hundred seventy-eight deltopectoral flaps were raised in 604 patients, 125 of which were delayed and 215 of which were used in previously irradiated beds. The rate of major flap necrosis was 16.9 percent and the overall rate of complications, 51.4 percent. Delay in creating the deltopectoral flap had no influence on the risk of complications and necrosis, whereas the use of the flap in a previously irradiated bed was associated with a significantly increased risk of major flap necrosis. The least flap loss occurred when the deltopectoral flap was used without tubulation for skin coverage only. Complications and flap necrosis occurred most frequently when flaps were tubulated in a reversed manner or used for lining of major portions of or for total oropharyngeal and hypopharyngeal reconstruction. The deltopectoral flap remains a useful, reliable, and versatile regional flap that can be used alone or in combination with other flaps in selected circumstances for major head and neck reconstruction.

Female↗

[A case report of hepatic metastasis from leiomyosarcoma of the rectum with right hepatic lobectomy].

A case of hepatic metastasis from leiomyosarcoma of the rectum submitted to right hepatic lobectomy is presented. Surgery for hepatic metastasis from intestinal leiomyosarcoma is rarely possible. The patient was a 67-year-old woman who was diagnosed as leiomyosarcoma of the rectum and underwent abdominoperineal excision of the rectum in fifteen months. Hepatic metastasis was detected by US, CT and angiography. Right hepatic lobectomy was performed, and the resected hepatic lesions were histologically identified as metastasis from leiomyosarcoma of the rectum. The patient is still alive 10 months after the second operation with no lesions of the liver.

Aged↗

[The effect of hyperglycemia on ischemic brain damage: relevance to the local cerebral blood flow].

The effect of hyperglycemia on ischemic brain damage in rats was studied by measuring the local cerebral blood flow (LCBF) using a transient middle artery (MCA) occlusion model. Rats, fasted except for water for 12-16 hours, were used. They were anesthetized with halothane and the stem of the left MCA was occluded for 2 hours by a microclip. Reperfusion was performed by removal of the clip. The rats were awaken from anesthesia after removal of the clip. Hyperglycemia was induced by intraperitoneal injection of 50% glucose and same volume of 50% D-mannitol or physiological saline were injected intraperitoneally 20 minutes before MCA occlusion in control rats. LCBF was measured by quantitative autoradiography using 14C-iodoantipyrine 2 hours after clipping and 2 hours after reperfusion. Some rats were prepared for neuropathological observation 72 hours after reperfusion. In hyperglycemic rats, plasma glucose concentration rose to over 500 mg/dl at the peak. A hyperglycemic state around 300 mg/dl was maintained during the experiments. Elevation of hematocrit and plasma osmolarity to the same degree were observed in both hyperglycemic and mannitol pretreated rats. On histological study ischemic neuronal cell damage was found to be more extensive in hyperglycemic rats than in the saline pretreated rats. At 2 hours after MCA occlusion, LCBF in the ischemic focus decreased significantly in hyperglycemic rats compared with the control. The reduction of LCBF was observed also in the contralateral non-ischemic side (P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Pharmacokinetics of 11C-BCNU in experimental brain tumor.

Wistar rats implanted intracerebrally with AA ascites tumor were injected seven or eight days later with 11C-labelled BCNU. Radioactive compounds in samples of plasma, tumor, and contralateral brain were identified after injection at intervals by doing chloroform extraction and thin layer radiochromatography. At 60 min after injection radioactivity levels were 56% higher in the tumor than in contralateral brain. This increase was due mainly to 2-chlorethyl isocyanate, which binds to amino groups and/or nucleic acid. The results demonstrated both a higher concentration and a faster decomposition of BCNU in the tumor.

Animals↗

Regional glucose utilization and blood flow in experimental brain tumors studied by double tracer autoradiography.

Coupling of regional glucose utilization (GLU) and blood flow (CBF) was examined in rats with implanted brain tumors (AA ascites tumor) by quantitative double tracer autoradiography using 18F-2-fluorodeoxyglucose and 14C-iodoantipyrine. Four to 13 days after implantation, the animals were injected with the two tracers to obtain autoradiograms from the same brain section before and after the decay of 18F. The autoradiograms were then analyzed by an image processor to obtain a metabolic coupling index (MCI = GLU/CBF). In the tumor, high GLU and low CBF were uncoupled to give a high MCI which implied anerobic glycolysis. In large tumors, the CBF was even lower. In the peri-tumoral region, GLU was reduced (especially in gray matter) and reduction was lowest around the larger tumors. CBF in the peri-tumoral region was also reduced, but this reduction became less as the distance from the tumor margin increased. These changes in the peri-tumoral region may be secondary to edema. The GLU and CBF of white matter was little influenced by the presence of tumors except for some reduction in these values in relation to the larger tumors. On a narrow margin of tumor and brain, corresponding to a zone of increased vascularity, CBF was moderately high. The MCI in the tumor was higher than in the cortex of the same as well as the opposite hemisphere. These findings indicate that the metabolism and blood flow of the tumor and surrounding brain are variable and directly related to tumor size.

Animals↗

Immunologic patterns of regional lymph nodes in squamous cell carcinoma of the floor of the mouth. Prognostic significance.

Histologic specimens from 43 patients with squamous cell carcinoma of the floor of the mouth treated exclusively by surgery were studied with special attention paid to the reactivity of regional lymph nodes. The lymph nodes were classified into four microscopic patterns of immune response: lymphocyte predominance for sinus histiocytosis, germinal center predominance, unstimulated, and lymphocyte depletion. No nodes of the lymphocyte depletion pattern were found. Correlations were then made between the patterns and survival rate at 5 year follow-up. The results showed that those patients with lymph nodes that demonstrated lymphocyte predominance had a better survival rate than patients with germinal center predominance and the unstimulated patterns. These correlations were independent of stage and metastatic nodal status and the differences were statistically significant (p less than 0.5). Morphologic assessment of immunologic activity in lymph nodes that drain carcinoma of the floor of the mouth appears to be of significant prognostic value.

Adult↗

Modified radical neck dissection for metastatic carcinoma of the thyroid. A reappraisal.

From January 1958 through December 1983, 56 modified radical neck dissections were performed on 47 patients with metastases to the cervical nodes from differentiated carcinomas of the thyroid. In nine patients, a second modified radical neck dissection was performed either simultaneously or at a later date. Lymph node clearance was performed on all but one surgical specimen. The number of nodes in each specimen ranged from 10 to 96, and the number of involved nodes ranged from 1 to 20. Thirty-eight of the 56 neck specimens contained four or more positive nodes. Seventeen patients were followed for 10 to 26 years, 18 patients for 5 to 9 years, and 5 patients for less than 5 years. Seven other patients died, three from other causes and four from lung metastases. There were no recurrences in the neck sides that would have been cleared if standard radical neck dissection had been performed. This reappraisal with long-term follow-up supports our initial impression that a modified radical neck dissection sparing the spinal accessory nerve, the sternocleidomastoid muscle, the internal jugular vein, or any combination thereof is an effective procedure for differentiated cancer of the thyroid, with preservation of good shoulder function and improvement in the cosmetic appearance of the neck.

Adenocarcinoma↗