Biomedical subjects

J J Loh

Publications and source records attributed to J J Loh.

17 recordsLinked to original sources

PubMed2001

High versus low dose rate intracavitary irradiation for adenocarcinoma of the uterine cervix.

BACKGROUND: Traditionally, low dose rate (LDR) brachytherapy has been used as a standard modality in the treatment of patients with carcinoma of the uterine cervix. The purpose of this work was to evaluate the effects of high dose rate (HDR) brachytherapy on patients with adenocarcinoma of the uterine cervix and to compare them with the effects of LDR brachytherapy. METHODS: From January 1971 to December 1992, 104 patients suffering from adenocarcinoma of the uterine cervix were treated with radiation therapy in the Department of Radiation Oncology, Yonsei University. LDR brachytherapy was carried out on 34 patients and HDR brachytherapy on 70 patients. In the LDR group, eight patients were in stage IB, six in IIA, 12 in IIB, three in IIIA and five in IIIB. External radiation therapy was delivered with 10 MV X-rays, 2 Gy fraction per day, total dose of whole pelvis 36-52 Gy (median 46 Gy). LDR radium intracavitary irradiation was performed with a Henschke applicator, 37-59 Gy targeted at point A (median 43 Gy). In the HDR group, there were 16 patients in stage IB, six in IIA, 32 in IIB and 16 in IIIB. The total whole pelvis dose of external radiation was 40-50 Gy (median 44 Gy), daily 1.8-2.0 Gy. HDR Co-60 intracavitary irradiation was performed with a remotely controlled after-loading system (RALS), 30-48 Gy (median 39 Gy) targeted at point A, three times per week, 3 Gy per fraction. RESULTS: The 5-year overall survival rate in the LDR group was 72.9, 61.9 and 35.7% in stage I, II and III, respectively and the corresponding figures for HDR were 87.1, 58.3 and 43.8% (p > 0.05). There was no statistical difference between the HDR group and the LDR group in terms of the 5-year overall survival rate from adenocarcinoma of the uterine cervix. There was a late complication rate of 12% in the LDR group and 27% in the HDR group. The incidence of late complications in stages II and III was higher in the HDR group than in the LDR group (31.6 vs 16.7% in stage II, 37.3% vs 12.5% in stage III, p > 0.05). No prognostic factors were evident in the comparison between the two groups. CONCLUSION: There was no difference in terms of 5-year survival rate in the patients with adenocarcinoma of the uterine cervix between those treated with HDR and those treated with LDR brachytherapy. Even though late complication rates were higher in the HDR group, most of them were classified as grade I. This retrospective study suggests that HDR brachytherapy may be able to replace LDR brachytherapy in the treatment of adenocarcinoma of the uterine cervix.

Adenocarcinoma↗

PubMed2001

Could ionizing radiation forestall cauliflower ear?

Repeated trauma to the ear very often results in "cauliflower ear." Many methods have been suggested to prevent an injured ear from demonstrating a cauliflowerlike deformity. The principles of treatment are evacuation of the hematoma, control of the reaccumulation of fluid, and maintenance of the cartilage contour. The authors studied the effect of ionizing radiation on deformed rabbit ears induced by repeated trauma. Twenty ears (10 rabbits) were used in the experiment. The animals were divided into four groups (control, preradiation, low dose, and high dose). Hematoma was produced by pounding the lateral side of the auricle 10 times with a 50-g weight at a height of 15 cm. The thickness of the injured and uninjured sites was measured, and histological analysis was performed for each group. The thickness of the ears of the irradiated groups was significantly less than the control group. The authors think that radiation treatment of repeatedly injured ears could prevent ear deformity, and could possibly be an adjunctive form of management of cauliflower ear in addition to hematoma evacuation and compression therapy.

Animals↗

PubMed1994

The role of radiation treatment in management of extrahepatic biliary tract metastasis from gastric carcinoma.

PURPOSE: To determine the proper role of radiation treatment in the management of patients with extrahepatic biliary tract metastasis due to recurrent gastric cancer. METHODS AND MATERIALS: Twenty patients with malignant biliary obstruction due to recurrent gastric carcinoma after gastrectomy were treated with palliative intent at the Yonsei University College of Medicine from 1986 to 1990. Treatment consisted of external drainage alone in 11 patients (Group I) and external drainage followed by radiation treatment in nine patients (Group II). Five of nine patients in Group II underwent external irradiation in combination with intraluminal brachytherapy using high dose rate Iridium-192 (Ir-192) sources within the expandable intrabiliary prosthesis, a Gianturco stent, inserted transhepatically at the site of obstruction. RESULTS: An excellent local response was observed in five of nine patients in Group II, in whom biliary patency was restored following treatment so that the external drainage catheter could be removed. Prolongation of median survival was observed in Group II (9 months) as compared to Group I (2 months). There were no serious treatment-related complications with this approach. CONCLUSION: This treatment approach with external radiotherapy +/- intraluminal brachytherapy could achieve effective palliation and improve the quality of life in selected patients with extrahepatic biliary metastasis from gastric carcinoma.

Adult↗

PubMed1991

Nodular hepatocellular carcinoma. Treatment with subsegmental intraarterial injection of iodine 131-labeled iodized oil.

Internal radiation therapy with subsegmental arterial injection of iodine 131(131I)-labeled iodized oil (Lipiodol; Laboratorie, Guerbet, France) was evaluated in 24 patients with nodular hepatocellular carcinoma (HCC) ranging from 2.5 to 8.0 cm in size. 131I Lipiodol (555 to 2220 MBq in 3 to 8 ml) was injected depending on the tumor size. Tumor reduction was seen in 88.9% of tumors smaller than 4.0 cm in diameter, 65.5% of tumors between 4.1 to 6.0 cm, and 25.0% of tumors larger than 5.1 cm. The tumor size reduction corresponded to the gradual drop of serum alpha-fetoprotein (AFP) levels and devascularization on follow-up angiography. Adverse reactions from treatment included fever, mild abdominal pain, nausea, and elevation of transaminases. These were mild and well tolerated by patients. This method provided long-term local control without complications related to the thyroid, lung, gastrointestinal tract, and bone marrow.

Adult↗

PubMed1991

Histological studies of surgically resected hepatocellular carcinoma following combined radiotherapy and hyperthermia.

Four cases of hepatocellular carcinoma (HCC) were surgically resected following combined radiotherapy (RT) and hyperthermia (HT). Complete necrosis of the tumor without viable tumor cell was found in one case and extensive tumor necrosis was observed in the other three cases; the percentage of necrosis in the specimens were 40%, 70%, and 80%, respectively. Histologic assessment showed mainly coagulative necrosis in the tumor with focal liquefactive necrosis. Cystic dilatation of sinusoids was observed in both tumor and nontumorous normal liver tissue. Other changes in normal liver tissue were unremarkable except for infiltration of inflammatory cells, fatty change, and proliferation of the bile ducts which can usually be seen beyond the area where any space occupying lesions are present. It is concluded that combined radiotherapy and hyperthermia can significantly induce coagulative necrosis of hepatocellular carcinoma with nonsignificant minimal histologic changes in adjacent nontumorous liver tissue.

Carcinoma, Hepatocellular↗

PubMed1990

Comparison of adjuvant radiotherapy and chemoradiotherapy following surgery in stage IE and IIE primary gastrointestinal tract non-Hodgkin's lymphoma.

Forty patients (median age 49.6 years) were treated for primary gastrointestinal lymphoma between 1979 and 1989. There were twenty-three cases of gastric lymphoma and seventeen cases of intestinal lymphoma. Following surgery, seventeen patients received postoperative chemoradiotherapy (ACOP) by the sandwich technique, seven patients received postoperative radiotherapy, and sixteen patients did not receive any other form of adjuvant treatment. Nineteen patients were stage IE and twenty-one were stage IIE. Stage IE disease was more prevalent in the gastric lymphoma group than the intestinal lymphoma group (p less than 0.01). At a median follow-up of 17 months (1-102 + months), 17 of 19 stage IE patients and 15 of 21 stage IIE patients remained alive. The survival rate was 90% in the postoperative chemoradiotherapy group and 83.3% in the postoperative radiotherapy group at five years, and 42.7% in the surgery alone group at four years, which showed statistical significance (p less than 0.01, p less than 0.05, each). Statistically improved survival rates were achieved with a postoperative chemoradiotherapy modality in intestinal lymphoma (p less than 0.01), stage IIE (p less than 0.01), intermediate grade by NCI criteria (p less than 0.01), poorly differentiated lymphocytic lymphoma (p less than 0.05), and diffuse histiocytic lymphoma (p less than 0.01) according to Rappaport classification, compared to those of the surgically treated only group. Three local relapses occurred in the operation alone group, and one in the adjuvant radiotherapy group which occurred simultaneously with distant lymph node recurrence. The pathologic stage of all of these relapsed patients was stage IIE-2. These results suggest that adjuvant chemoradiotherapy in completely resected localized gastrointestinal non-Hodgkin's lymphoma can decrease local and systemic relapse resulting in long-term disease free survival and overall survival compared to operation alone.

Adolescent↗

PubMed1990

Male breast cancer--a 20-year review of 16 cases at Yonsei University.

Sixteen cases of male breast cancer seen over a 20-year period were reviewed. The causes of cancer of the male breast are no better understood, but major alterations in hormonal environment could be a significant factor. Some clinical characteristics correspond well with the results of other series. The median age at presentation was 61.7 years. The most frequent initial symptom was a painless mass, and the incidences of nipple discharge, central tumor location, and axillary node involvement were high. Males also had a higher incidence of local advancement which was associated with a longer delay in seeking treatment and small breast tissue. The pathologic type was infiltrating ductal type in all cases except one, and all cases showed favorable nuclear grade. Estrogen receptor analysis was performed from the tumor of 2 patients. Both of them showed a high receptor level. There was no locoregional relapse in 5 patients who received adjuvant radiotherapy in contrast to the 2 relapses in 3 patients who underwent surgery alone. And three of the five patients who received radiotherapy suffered from systemic metastasis which suggested the important role of adjuvant chemotherapy as well as radiotherapy. In light of the encouraging results about adjuvant chemotherapy in the treatment for female breast cancer with axillary lymph node involvement, it would be desirable to extend this policy to male breast cancer.

Adenocarcinoma↗

PubMed1990

Postoperative radiotherapy for stage IB carcinoma of the uterine cervix.

Sixty patients, treated with postoperative radiation therapy following radical hysterectomy and pelvic lymphadenectomy for stage lb carcinoma of the uterine cervix between Jan. 1980 and Dec. 1984 at Department of Radiation Oncology, Yonsei University College of Medicine, were retrospectively analysed. The minimum follow-up period was 5 years. The indications for postoperative radiotherapy were positive pelvic lymph node (34 pts), a large tumor size more than 3 cm in longest diameter (18 pts), positive surgical margin (10 pts), deep stromal invasion (10 pts), and lymphatic permeation (9 pts). The overall 5-year survival rate was 81.8%. The univariate analysis of prognostic factors disclosed tumor size (less than 3cm, greater than or equal to 3cm) and the status of the surgical margin (positive, negative) as significant factors (tumor size; 88.1% vs 6.3%, surgical margin; 85.5% vs 60%, p less than 0.05). Age (less than or equal to 40, greater than 40 yrs) was marginally significant (90.2% vs 73.1%, p less than 0.1). Multivariate analysis clarified two independent prognostic factors; tumor size (p = 0.010) and surgical margin (p = 0.004). Analysis of the tumor factors with the radiation dose disclosed a better survival rate for patients with a positive surgical margin who were given over 50 Gy than for those who were given below 50 Gy in patients (4/4, 100% vs 2/6, 33.4%; p = 0.06). Significant complications requiring surgical correction were not observed. In conclusion, it is believed that the status of the surgical margin and tumor size both have important prognostic significance, and that a radiation dose over 50 Gy is advisable for patients with a positive surgical margin.

Adult↗

PubMed1989

Current status and future aspects on treatment of liver cancer.

Among 80 patients with advanced hepatocellular carcinoma, treated by systemic chemotherapy, 19 patients (24%) achieved partial response or stable disease. The median survival time of responders was 20 weeks. Radioiodinated fatty acid esters ([131I]lipiodol) are localized in hepatoma tissue for a considerable time. Taking advantage this phenomenon, there is a potential therapeutic effect of [131I]lipiodol, since the radioactive oil can deliver a therapeutic dose of internal radiation. The response rate of patients who had a small hepatoma (less than 5 cm in diameter) was 80%. Among 25 responders, 12 cases are alive after more than 1 year. A pilot study of hyperthermia, using a heating device capable of delivering radiofrequencies, combined with radiotherapy or chemotherapy, demonstrated that this modality is safe and effective in the treatment of advanced hepatocellular carcinoma. Of the 19 patients treated, 47% showed partial remission or stable disease. The median survival time of 9 responders was 9 months. Among the 9 responders 3 patients survived for over 1 year.

Adult↗

PubMed1989

Primary malignant lymphomas of the central nervous system: radiotherapy results in 12 cases.

Twelve patients with primary lymphomas of the central nervous system were treated in the Department of Radiation Oncology, Yonsei University College of Medicine, between 1976 and 1987. There were seven males and five females ranging from 19 to 63 years of age. They had single (6 cases) or multiple (6 cases) discrete intracerebral nodules. All patients were treated with radiation therapy. Surgical resection was performed in five cases and intrathecal chemotherapy with methotrexate was performed in seven cases after radiotherapy. All patients except one had received whole brain irradiation with a median dose of 4000 cGy. The radiation dose for a primary tumor was 4800-6000 cGy (median 5560 cGy). Initial response to radiation was excellent with a 91.7% complete response rate, but late recurrences were noted and the median survival was 42.3 months. Intracranial recurrences were observed in two patients who received less than 4000 cGy to the whole brain without intrathecal chemotherapy. Although intracranial recurrence was not seen in the patients receiving intrathecal chemotherapy after radiation, a high incidence of necrotizing leukoencephalopathy was noted. High dose irradiation with a minimum of 4000 cGy to the whole brain and more than 5000 cGy to the primary tumor is recommended for the treatment of primary CNS lymphomas. Combined use of chemotherapy should be carefully attempted because of the increased toxicity.

Adult↗

PubMed1989

Cooperative clinical studies of hyperthermia using a capacitive type heating device GHT-RF8(Greenytherm).

Yonsei Cancer Center developed an RF(Radiofrequency) capacitive type heating device, GHT-RF8(Greenytherm) in cooperation with Green Cross Medical Corp., Korea in 1986 for the first time in Korea. Cooperative clinical studies of hyperthermia for the treatment of cancer using GHT-RF8 were conducted by Yonsei Cancer Center in collaboration with the Presbyterian Medical Center, Chonju, Korea. A total of forty patients with various histologically proven malignant tumors, including superficial (N = 13) and deep-seated tumors (N = 27), were treated with this newly developed heating device in conjunction with radiotherapy (N = 38) or chemotherapy (N = 2) at two different institutes between October 1986 and September 1987. These patients were locally far advanced or recurrent cases and considered to be refractory to conventional cancer treatment modalities. Radiotherapy was given in 200cGy per day, five times a week fractionations with a total tumor dose of 50-60Gy in 5-6 weeks. Within an hour after radiotherapy, the RF capacitive type of hyperthermia was given two times a week for a total of 4-10 treatment sessions and an attempt was made to maintain the tumor temperature at 41-45 degrees C for 30-60 minutes. Of forty patients treated, 14 patients with deep-seated tumors showed complete response and 20 patients showed partial response. The overall response rate was 85% (34 out of 40 patients) and only 6 patients showed no response. Complications from this treatment were mainly burns, superficial first degree burn in 2 cases, second degree in 4 cases and subcutaneous fat necrosis was observed in 2 cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1983

Adjuvant chemotherapy with cis-diamminodichloroplatinum II and 120-hour infusion 5-fluorouracil in Stage III and IV squamous cell carcinoma of the head and neck.

A prospective study was carried out to investigate the effectiveness and toxicity of three courses of combination high-dose bolus CDDP and 120-hour continuous infusion 5-FU every three weeks prior to definitive surgery and/or radiation therapy in 35 patients with locally advanced Stage III and IV squamous cell carcinoma of the head and neck. Twenty-two patients (63%) achieved a CR and 11 (31%) a PR after three cycles of chemotherapy, for an objective response rate of 94%. Toxicity was clinically acceptable. Nausea and vomiting occurred in 23 of 35 (66%) without any patients discontinuing therapy for this reason. Leukopenia in 13 (37%) and reversible azotemia in six (17%). Following three courses of chemotherapy, 13 patients had surgical resection and 12 patients had radiation therapy. Ten of these 35 patients had no pathologic evidence of cancer in the surgical specimen or preradiation therapy biopsy. Only two patients of those achieving a complete objective response have relapsed. However, the median follow-up has been short. The authors concluded that three courses of CDDP and 5-FU is a highly effective and safe adjuvant treatment in patients with advanced carcinoma of the head and neck.

Carcinoma, Squamous Cell↗

PubMed1981

Newt forelimb regeneration blastemas in vitro: cellular response to explanation and effects of various growth-promoting substances.

Macromolecular synthesis was studied in cultured newt forelimb blastemas. Late bud stage blastemas were explanted into organ culture and thus denervated. When the response of the blastemas to explantation was examined, it was found that a peak in 3H-leucine incorporation occurred at 2 hr of incubation, and a similar peak in 3H-thymidine incorporation occurred at 3-4 hr. After these initial increases, both parameters declined to levels lower than those determined at the time of explantation. The peaks in macromolecular synthesis reported here in vitro are similar to those observed in blastemas in vivo after denervation (Singer, '74). In the second part of the study, the ability of various growth-promoting substances to stimulate DNA synthesis in cultured blastemas was investigated. Increasing concentrations of fetal bovine serum caused increased levels of 3H-thymidine incorporation, with maximal stimulation at 30% serum. Newt brain extract (NBVE) was as effective as additional serum, with optimal stimulation at 100 micrograms total NBE protein per ml culture medium. Fibroblast growth factor (FGF), derived from brain tissue, at a concentration of 10 ng/ml was as effective as both 30% serum and the optimal concentration of NBE. Epidermal growth factor (EGF) produced a maximal effect at 1 ng/ml. Neither nerve growth factor nor the platelet-derived growth factor were stimulatory. Bovine insulin was highly active in stimulating DNA synthesis at concentrations from 1-10 micrograms/ml. The requirement of nerves for blastemal development, as well as the possible roles of the various growth-promoting substances in this process, are discussed.

Animals↗

PubMed1981

Complete eradication of squamous cell carcinoma of the esophagus with combined chemotherapy and radiotherapy.

Chemotherapy (with 5-fluorouracil and either mitomycin-C or cis-platinum) combined with radiotherapy was used either for palliation or as preoperative therapy in 67 patients with squamous cell carcinoma of the esophagus. In 25 patients having chemotherapy and 5000-6000 rads, good local palliation was obtained in 11 (49%) without surgery. In the remaining 25 patients, swallowing was restored with a variety of procedures (primarily Celestine tube or gastric bypass). The average survival time was seven months and two patients are still alive at 9 and 12.5 months. Of 42 patients receiving preoperative chemotherapy and radiotherapy, 35 had surgery. Of these, 13 (37%) had complete eradication of their tumors with no histologic evidence of carcinoma in the resected esophagus or associated lymph nodes. In another six (17%), the only evidence of tumor was small microscopic foci of cancer cells in the wall of the esophagus. The 6-, 12-, and 24-month survival rates for patients having surgery after the combined preoperative chemotherapy and radiotherapy were 83 per cent, 52 per cent, and 30 per cent, respectively. These results are far superior to those previously obtained.

Adult↗

PubMed1981

Eradication and palliation of squamous cell carcinoma of the esophagus with chemotherapy, radiotherapy, and surgical therapy.

Between April, 1977, and March, 1981, 86 unselected patients with proved squamous cell carcinoma of the esophagus were treated with a combination of chemotherapy and radiotherapy followed by operation whenever feasible. The preoperative chemotherapeutic agents used initially were 5-fluorouracil, and mitomycin C. After December, 1979, cis-platinum was used instead of mitomycin C. Radiotherapy (3,000 rads) of the tumor was begun at the same time as the chemotherapy. An esophagectomy was performed on suitable candidates 3 to 4 weeks after the chemotherapy and radiotherapy were completed. The mucosal lesion disappeared in 69 of the 86 patients, and dysphagia was relieved at least temporarily in 57 of 62 patients. Recurrent dysphagia resulting from fibrosis at the tumor site caused a secondary stenosis in 11 patients. Excellent palliation was obtained in five patients with bronchoesophageal fistulas who had an initial substernal gastric bypass followed by chemotherapy and radiotherapy. Of the 48 patients who had an esophagectomy, 15 (31%) had no tumor in the resected specimen. Eleven of these 15 patients are still alive with no evidence of disease. All patients with a lesion less than 5.0 cm in length had complete regression of the tumor. We believe that this combination of chemotherapy, radiotherapy, and surgical therapy provides excellent palliation, increases resectability, and has a potential for cure.

Adult↗

PubMed1980

Combined modality therapy for advanced head and neck cancer.

Seventy-five patients with stage III and IV squamous cell cancer of the head and neck, previously untreated, had two courses of chemotherapy with cis-platinum, Oncovin and bleomycin, followed by radical surgery, radiotherapy or both. Response to chemotherapy (complete and partial) was high (80 percent). In 36 patients radical surgery became possible. The overall survival improved statistically in patients who achieved complete or partial response to chemotherapy compared with those who had minimal or no response. Patients with well to moderately well differentiated cancer, or stage III disease, had a statistically better prognosis than patients with poorly differentiated cancer, or stage IV disease.

Bleomycin↗

PubMedDate not supplied

cis-platinum and 5-fluorouracil as initial therapy in advanced epidermoid cancers of the head and neck.

A total of 44 patients with previously untreated Stage IV squamous cell carcinomas of the head and neck were treated with a combination of cis-platinum (100 mg/sq m) and 96-hour infusion of 5-fluorouracil (5-FU) (1,000 mg/sq m/day) in two courses or with cis-platinum (100 mg/sq m) and 120-hour infusion of 5-FU (1,000 mg/sq m/day) in three courses. In the 26 patients receiving the two course regimen, the tumor response rate was 88.5%. In five of the 26 patients complete disappearance of the tumor was achieved; partial remission was obtained in 18 of 26 patients. The main side effects were nausea and vomiting (70%), leukopenia (27%), and mild-to-moderate renal toxicity (27%). In the 18 patients who received the three course regimen of 5-FU and cis-platinum, there were 11 (61%) complete responses, 6 (33%) partial responses, and 1 (6%) minimal response. The incidence of complete response was increased with each course given. No added toxicity was observed with surgery or radiotherapy.

Adult↗