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Biomedical subjects

G Kohama

Publications and source records attributed to G Kohama.

At least 37 records · Page 2Linked to original sources
PubMed1996

Supraperiosteal flap technique versus mucoperiosteal flap technique in cleft palate surgery.

Recent animal experiments have shown that palatal repair without denudation of bone leads to a superior dento-alveolar development. The aim of this clinical study was to evaluate the peri- and postoperative course and the dento-alveolar development of the deciduous dentition in Japanese ULCP, and CP patients up to 5 years after two different types of palatal repair. One of the methods, the Kohama (1991) supraperiosteal flap technique, is performed without denudation of the bony palate, while the other, the Wardill (1937) push-back technique, results in areas of denuded bone. It was concluded that the supraperiosteal technique can be performed successfully in approximately the same amount of time as the push-back technique. Re-epithelialization of the wound areas after supraperiosteal repair takes about 1 week, which is one third of the time associated with healing after the push-back technique. Arch depth of the deciduous dentition after the supraperiosteal technique is superior compared to the push-back technique. The question of whether or not the supraperiosteal technique produces more favorable dento-alveolar development than the mucoperiosteal technique in the permanent dentition in humans has to be elucidated in future research.

Analysis of Variance↗
PubMed1995

Two cases of tongue cancer treated with intra- and peri-tumoral injection of recombinant interleukin-2 alone: immunohistochemistochemical considerations to clinical tumor response.

SUBJECTS AND METHODS: Two cases with stage II tongue cancer who exhibited different responses to intra- and peri-tumoral administration of rIL-2 alone are presented. Special consideration is given to the relationship between tumor responses to rIL-2 and clinicopathological and immunohistopathological findings. RESULTS: The patient who responded completely to treatment showed an exophytic tumor growth pattern, low-grade cancer invasion, and predominant infiltration of CD8+ lymphocytes over CD4+ lymphocytes in cancer cell nests. The non-responder showed endophytic tumor growth, high-grade cancer invasion, and uniform distribution of both CD4+ and CD8+ lymphocytes in cancer cell nests. CONCLUSIONS: Distribution of adequate amounts of T lymphocytes subsets may be necessary in order for good tumor response to biotherapy with rIL-2; other clinical and histopathological variables predicting the effect for cancer chemotherapy remain to be identified.

Aged↗
PubMed1992

Significance of glutathione S-transferase-pi as a tumor marker in patients with oral cancer.

BACKGROUND: The authors analyzed the clinical usefulness of glutathione-S-transferase-pi (GST-pi) as a tumor marker in patients with oral cancer. METHODS: GST-pi levels in plasma of 61 patients with oral squamous cell carcinomas, 65 patients with benign oral diseases, and 78 healthy subjects were investigated with the sandwich enzyme-immunoassay (EIA) system. RESULTS: Elevated GST-pi levels in plasma were observed in patients with oral cancer, but patients with benign oral diseases had normal GST-pi levels. More than 70% of patients with Stage III or IV oral cancer and more than 50% of those with Stage I and II disease had elevated levels of GST-pi in plasma. Elevated levels of GST-pi in plasma were also discovered in most patients with tumor recurring after surgery before recurrence was detected clinically. GST-pi also was found to be a useful marker for evaluating the response to chemotherapy, for monitoring postoperative tumor resectability or tumor burden, and for predicting the recurrence of tumor in patients with oral cancer. CONCLUSIONS: GST-pi is considered to be a useful aid for early diagnosis, predicting tumor extent, and determining parameters of treatment efficacy and prognosis for oral cancer.

Antigens, Neoplasm↗
PubMed1992

[Clinical and histological effects of preoperative chemotherapy for squamous cell carcinoma of the tongue].

According to the effect of preoperative chemotherapy for tongue cancer, if the operation method is modified, the modality of treatment for tongue cancer will contribute to preserve the tongue in terms of function and aesthetics as well as improve the quality of life. A clinicopathologic study on 81 patients with tongue cancer was conducted to elucidate the relationship between clinical and histological effects of preoperative chemotherapy with a single agent and multiple-drug regimens, in order to determine the safe surgical margins in the resection of squamous cell carcinoma of the tongue. Fifty patients were treated with bleomycin alone, sixteen with bleomycin and methotrexate and another fifteen with bleomycin, OK-432 and cisplatin. Multiple-drug regimens resulted in greater response rates than the single agent, but there was not always agreement in the relationship between the tumor regression rate and the histological effects of chemotherapy. The histological effects, including the residual aspects of the tumor cell population, were associated with the grade of histological malignancy according to the mode of tumor cell invasion, mitotic index of tumor cell, the tumor differentiation, the degree of stromal lymphocyte infiltration and cellular atypism. These data indicate that special consideration should be also given to the degree of histological malignancy for biopsied specimen, in addition to the tumor regression rate, in determining safe surgical margins and in the modality of treatment of tongue cancer.

Adult↗
PubMed1989

[Clinical analysis of 26 cases of multiple primary cancer].

Of 412 head and neck cancers in the Department of oral Surgery, Sapporo Medical College from 1976 to 1987, 26 cases (6.3%) were multiple primary cancers. One of these cases was triple cancer. The ages of these 26 cases ranged from 42 to 81 (average 61 year-old) with 20 males and 6 females (3.3:1). As to the interval between the first and second cancer, five cases (20%) were synchronous and twenty cases (80%) were metachronous in our series. Of the five synchronous, three were found by careful examination at the time of admission to our department. The stomach and head and neck cancers were frequently observed as the first cancer of metachronous cases. Second primary cancers occurred in the head and neck region were 64% and those in other regions were 36%. On the other hand, digestive cancer was predominant in the additional cancer to the index cancer (66.7%). These numbers emphasize that patients with head and neck cancers are in a cancer-prone group that develops digestive cancers. These findings have important implications in follow up policy.

Adenocarcinoma↗
PubMed1989

[Secondary metastasis after excision of oral squamous cancer without local recurrence].

A secondary metastasis after surgery was uncovered in 12 out of 73 cases of oral squamous cancer. The clinical and histological characteristic tendencies of the metastasis of these 12 cases were the tongue as the tumor site (11/12), and an aggressive invasion in the tumor-host borderline with 2 of Gr, 3, 5 of Gr. 4C and 5 of Gr. 4D, according to the grading of Yamamoto and Kohama (1982). The control of these metastases was not easy because of their multiple and extra-nodal spread. Tumor-free survival occurred in 4 out of 11 (36.3%). Therefore, in some situations, a prophylactic neck dissection would seem to be recommended.

Aged↗
PubMed1989

[Immunohistochemical localization of laminin and its relation to the grade of histological malignancy in oral cancer].

The immunohistochemical localization of Laminin has been investigated with a monoclonal antibody in biopsy specimens from 27 patients with an invasive squamous cell carcinoma of the oral cavity. In normal mucosa, laminin was found distributed in a linear pattern in the epithelial-stromal junction, around the blood vessels, the nerve fibres, and the skeletal muscle bundles. In the cancerous tissues a variety in the linear staining around the cancer cell nests was seen. Extreme attenuation or complete loss of the linear staining of laminin was demonstrated in 8/27 specimens, and these tumors histologically showed a high grade of malignancy with H.E. staining.

Basement Membrane↗
PubMed1988

[Cytophotometric analysis of the nuclear DNA content in oral squamous cell carcinoma--relation between nuclear DNA content and clinico-pathologic findings].

Cytophotometric analysis has been performed on Feulgen-stained nuclei in smears taken from 48 biopsy specimens of squamous cell carcinoma of the oral cavity. The results were correlated with the clinico-pathologic findings of the tumor. DNA histograms were graded into three patterns: P-I (2C-2C), P-II (2C-6C) and P-III (2C-beyond 6C). DNA patterns of the carcinoma of the clinical stage I, II tended to be P-I, II and those of stage III, IV were mostly P-II, III. DNA patterns of carcinomas which were well differentiated and poorly pleomorphic with a few number of mitoses, were mostly P-I, whereas those which were poorly differentiated and remarkably pleomorphic with a many number of mitoses were mostly P-III.

Carcinoma, Squamous Cell↗
PubMed1988

[Type-oriented surgery of oral cancer based on its clinical staging and histological grading].

Type-oriented surgery for oral cancer according to its clinical staging and histological grading were applied for a total of 204 cases of oral squamous cell carcinoma. These cases were classified not only by staging (St.) into 111 at St. I, II and 93 at St. III, IV, but also by grading (Gr.) into 33 of Gr. 1, 80 of Gr. 2, 69 of Gr. 3 and 22 of Gr. 4 with a total points system consisting of differentiation, mitosis, nuclear atypism, mode of invasion and lymphocytic infiltration. The four operation methods used and their indication were local excision for St. I, II + Gr. 1 in 33 cases, partial resection for St. I, II + Gr. 2, 3 and St. III, IV + Gr. 1, 2 in 115 cases, composite operation for St. I - IV + Gr. 3, 4 in 52 cases and wide resection for St. IV + Gr. 2, 3 in only 4 cases, resulting in observed survival rates of 28/30 (93.3%), 85/106(80.1%), 30/48 (62.5%) and 3/3 (100%), respectively. The cumulative survival rate estimated by staging was 86.7% for St. I, II and 77.6% for St. III, IV. Among these, cases with a high grade of histological malignancy (Gr. 4) at any clinical stage had the most unfavorable survival rate, 34.7%. Therefore, it should be emphasized that composite operation with wide local excision is necessary for such patients in order to obtain a better prognosis.

Carcinoma, Squamous Cell↗
PubMed1987

Acinic cell carcinoma of minor salivary gland origin.

We describe a case of acinic cell carcinoma of the right soft palate in a 65-year-old man. The primary symptom was a painless swelling of the palate, which was partially ulcerated with a granulomatous appearance. Ultrastructurally, the tumor cells were mainly composed of differentiated acinuslike cells containing numerous round secretory granules identical to those in normal serous salivary glands. The tumor cells frequently contained numerous long crystalloid structures in the cytoplasm. Furthermore, tumor cells demonstrating degrees of squamous differentiation were present. These cells contained intracytoplasmic keratin filaments and a few keratohyaline granules. They formed a glandular acinar space in direct contact with the typical acinic cells with secretory granules. These observations suggest that acinic tumor cells have a degree of multipotentiality.

Aged↗
PubMed1984

Immunohistologic detection of lymphocyte subpopulations infiltrating in human oral cancer with special reference to its clinical significance.

Cancer tissues from 30 patients with squamous cell carcinoma of the oral cavity were examined immunohistopathologically as to the responsiveness of the host against its own cancer cells in both biopsy and surgically resected specimens from the same patients. Subpopulations of the infiltrating lymphocytes in cancer tissues were identified on paraffin-embedded serial sections by a modified indirect immunoperoxidase technique (PAB method) in which it was combined with peroxidase-antiperoxidase (PAP) complex and avidin-biotin system with rabbit anti-human B-cell, peripheral T-cell sera. Macrophages were also identified by nonspecific acid esterase staining. T-cells were predominant over B-cells in 26 of 30 tissues in biopsy specimens and 23 of 30 in surgically resected specimens with bleomycin treatment. T-cell infiltration in the peripheral region of the tumor was more prominent than that in the stroma among the cancer nests. T-cells surrounded the cancer nests, occasionally accumulated around the cancer cells, infiltrated at the marginal part of the cancer nests, and frequently produced perivascular massive accumulations. B-cells and macrophages, on the other hand, were almost absent or negligible around cancer tissues. The grade of T-cell infiltration, especially in biopsied specimens, was correlated well to the size of the tumor, and also more marked significantly in patients without cervical lymph node metastasis than in those with lymph node metastasis. Furthermore, there was a significant correlation between the grade of T-cell infiltration at the peripheral region of the invading cancer mass in initial biopsy specimens and the clinical tumor regression rates with bleomycin treatment, but it did not correlate to the surgically resected specimens. These facts suggest that T-cells might inhibit the development and spreading of the cancer cells, and that the T-cell infiltration correlates with the clinical course or prognosis of the oral cancer patients.

Adult↗
PubMed1984

Electrical burns of lip and mouth in children. Report of 2 cases.

2 cases of electrical burns of the oral cavity in young children are reported. Both cases were treated conservatively. 1 of the patients, now that 3 years have passed, has a slight scar with a slight deformity of lower and upper lips. We are planning reconstructive surgery within a short time. There are no functional or developmental disturbances. The main cause of electrical burns in young children is biting or sucking the free end of live extension cords or placing sockets into the mouth. Since most of these injuries are from low-voltage, electric circuits are localized to the surroundings of the mouth. However, the injuries are small or narrow, but reach much deeper than initially appear. Therefore, the scar may be small but the deeper tissue may sustain more extensive damage than expected.

Burns, Electric↗
PubMed1984

Lymphocyte subpopulations and T-cell subsets in human oral cancer tissues: immunohistologic analysis by monoclonal antibodies.

A series of T-cell-specific monoclonal antibodies (Leu-1, Leu-2a, and Leu-3a) and B-cell-specific monoclonal antibody (HLB-1) were used to detect the localization and intensity of infiltration of lymphocyte subpopulations and T-cell subsets in frozen sections of 17 patients with the oral cancer. The vast majority of the lymphocyte infiltrates in the oral cancer tissues were reactive with Leu-1. In contrast, B cells were detectable with HLB-1 in only 2 of 17 cases. Leu-2a-positive cells were dominant in four cases, whereas Leu-3a positive cells were dominant in only three cases. In seven cases, both cells infiltrated to the same degree. Leu-2a positive cells tended to be dominant in the cases with earlier clinical stages.

Adult↗
PubMed1984

[MTX-BLM therapy for squamous cell carcinoma of the oral cavity].

Effects of Methotrexate (MTX) alone and sequential combination chemotherapy of MTX and Bleomycin (BLM) were evaluated in 29 primary cases of squamous cell carcinoma of the oral cavity. MTX 50mg or 500 mg was administered intravenously once a week for a total dose of 100 to 200 mg in 10 cases and 1000 mg in 19 cases. In the cases of MTX 500 mg, CF (Leucovorin) rescue was given subsequently. BLM 15 mg was also administered intravenously twice a week for a total dose of 45-90 mg in 25 cases, so that 4 patients received MTX alone, 6 were transferred from BLM to MTX treatment and 19 were transferred from MTX to BLM. Objective response rate to MTX in cases of single and prior administration was 12/23 (52.2%). Treatment was found to be effective clinically in cases of exophytic growth type and histologically in cases of well differentiated types of tumor cells and well defined types of tumor-host borderline. Objective response rate to MTX treatment followed by BLM was 12/19 (57.9%) while that of BLM switched to MTX was 3/6 (50.0%). Side-effects, such as myelosuppression and anorexia, were observed in 12/29 cases given MTX, while, in only one case given BLM, skin reaction was observed. With respect to side-effects and the general preoperative condition of patients, the MTX to BLM course seemed to be better than that in which BLM was switched to MTX. Moderate-dose MTX: CF rescue + small-dose BLM therapy for oral cancer was, therefore, concluded to be useful as a preoperative adjuvant chemotherapy.

Adult↗
PubMed1983

Mode of invasion, bleomycin sensitivity, and clinical course in squamous cell carcinoma of the oral cavity.

Forty patients with squamous cell carcinoma of the oral cavity were treated with bleomycin prior to undergoing surgery. The degree of the clinical effect of bleomycin and the postoperative clinical course of each case were estimated from the viewpoint of correlation with the mode of invasion. A strong correlation was found among the mode of invasion, bleomycin sensitivity, and clinical course. A slight effect of bleomycin and poor prognosis existed in the group with a diffuse invasion of mode of invasion, while the greatest effect of bleomycin and good clinical course were achieved in the group with a well-defined tumor-host borderline.

Adult↗
PubMed1983

Clinical course of diffuse invasive carcinoma of the tongue excised after Bleomycin treatment.

According to the mode of invasion across the tumour-host boundary which was described and graded by Jacobsson et al. (1973), the clinical course of diffuse invasive squamous cell carcinoma of the tongue (grade 4) was investigated comparing it with the other grade groups (grades 1-3). Metastasis to regional lymph nodes and local recurrence after surgery were extremely common in grade 4. These local recurrences led to death in most grade 4 cases while a better clinical outcome was achieved in the other grades. Grade 4 was further subclassified into a cord-like type (grade 4 C) and a diffuse type (grade 4 D) from the histological features of the tumour-host interface, with the latter being more malignant than the former.

Adult↗
PubMed1982

Morphological studies of the velopharyngeal orifice in cleft palate.

Silicone rubber impressions and plaster casts were made preoperatively to evaluate the velopharyngeal orifice areas in 91 children with cleft palate aged one year and two months to two years and five months. Cleft width was large in children with cleft lip and palate (CLP) than in children with cleft palate alone (CP). Velopharyngeal orifices were classified into four types based upon their area and shape. It was concluded that the classification might be useful in planning palatoplasty.

Child, Preschool↗