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J Y Ko

Publications and source records attributed to J Y Ko.

At least 37 records · Page 2Linked to original sources
PubMed2000

Dysphagia after radiotherapy: endoscopic examination of swallowing in patients with nasopharyngeal carcinoma.

Dysphagia is a late sequela compromising the lives of more than one fourth of patients with nasopharyngeal carcinoma (NPC) who survive long after radiotherapy. By using fiberoptic endoscopic examination of swallowing as a modality for dysphagia evaluation, we were able to easily recognize the functional and anatomic changes in 31 dysphagic NPC patients. The majority of patients were found to aspirate after the act of swallowing (77.4%). Seventeen (54.8%) had tongue atrophy, and 9 (29%) had vocal cord palsy. Dysfunctions such as dry mouth (45.2%), velopharyngeal incompetence (58%), premature leakage (41.9%), delay or absence of swallow reflex (87.1%), poor pharyngeal constriction (80.6%), pharyngeal residue retention (83.9%), penetration or aspiration (93.5%), and silent aspiration (41.9%) were noted in these patients. Multiple dysfunctions were demonstrated in each patient. Abnormality of pharyngeal constriction and/or aberrant upper esophageal sphincter function played the major role in the postswallow aspiration of these irradiated NPC patients. Clinically compromised patients (weight loss of > or =5 kg in 1 year or pneumonia) had more of the above anatomic and functional impairments. The radiation dosage and volume bore no correlation to the time of symptom onset, or to the occurrence of functional changes.

Adult↗
PubMed2000

DNA content of nasopharyngeal carcinoma: an independent prognostic indicator.

The purpose of this study was to examine whether tumor DNA content correlated with prognosis in nasopharyngeal carcinoma (NPC). DNA flow-cytometric analysis in fresh specimens of nasopharyngeal biopsy from 123 patients with clinical suspicion of NPC was collected initially. Histopathologic study and successful flow-cytometric analysis had 28 lymphoid hyperplasias and 87 NPCs. Seventeen NPC patients were treated elsewhere and were excluded. A total of 98 patients, including 28 lymphoid hyperplasias and 70 NPCs, formed the materials of this study. There were 34 (49%) diploid and 36 (51%) aneuploid in NPC patients. No lymphoid hyperplasias were aneuploid. The mean of S-phase fraction was higher in NPC than in lymphoid hyperplasia (P < .001), indicating higher cellular activity in NPC. DNA content failed to associate with age, gender, pathology, distant metastasis, and stage, indicating that DNA content was an independent prognostic indicator and possibly a clinical parameter. The log-rank test of overall survival curves was significant for stage (P = .002) and DNA ploidy (P = .042); it was almost significant for S-phase fraction (P = .057). Because the follow-up duration was not long enough, univariate and multivariate analysis were not significant for stage, ploidy, and S-phase fraction, except for distant metastasis. It is also most likely colinearity of clinical stage and distant metastasis that explained why clinical stage could not show significance in prognosis. Interestingly, the DNA content appeared to be a potential prognostic parameter in overall survival, although it was not statistically significant (P = .052). Our data suggested that NPC patients with aneuploid DNA and high S-phase fraction tend to have poor prognosis and should be treated more aggressively, even in the early stage of the disease.

Adult↗
PubMed1999

Intravascular ultrasound comparison of chronic recoil among different stent designs.

Intravascular ultrasound studies were acquired in 70 native coronary artery lesions after implantation and at follow-up of Palmaz-Schatz, GFX, NIR, and CrossFlex stents. Chronic stent recoil was minimal in the Palmaz-Schatz, GFX, and NIR stents; however, there was small, but significant chronic recoil of the CrossFlex stent.

Coronary Disease↗
PubMed1999

Circulating intercellular adhesion molecule 1 (ICAM-1), E-selectin and vascular cell adhesion molecule 1 (VCAM-1) in head and neck cancer.

The sera from patients with nasopharyngeal carcinoma (n = 30), oral carcinoma (n = 22) and laryngeal carcinoma (n = 22) was extracted before treatment. The concentration of circulating intercellular adhesion molecule 1 (ICAM-1), E-selectin and vascular cell adhesion molecule 1 (VCAM-1) was measured by enzyme-linked immunoassay and compared with those from normal subjects (n = 20). The concentration of circulating ICAM-1, E-selectin and VCAM-1 was significantly increased in nasopharyngeal carcinoma. Correspondingly, VCAM-1 and E-selectin were significantly increased in laryngeal carcinoma, whereas only E-selectin was elevated in oral carcinoma. The concentrations of these adhesion molecules did not significantly differ with respect to the early and late stages of these carcinomas. Elevated levels of soluble adhesion molecules in the sera of cancer patients at three different head and neck regions, although appearing to be implicated in these tumour formations, may be unrelated to tumour progression.

Adult↗
PubMed1999

Induction with mitomycin C, doxorubicin, cisplatin and maintenance with weekly 5-fluorouracil, leucovorin for treatment of metastatic nasopharyngeal carcinoma: a phase II study.

The combination of cisplatin and 5-fluorouracil (5-FU) (PF) is the most popular regimen for treating metastatic nasopharyngeal carcinoma (NPC) but it is limited by severe stomatitis and chronic cisplatin-related toxicity. A novel approach including induction with mitomycin C, doxorubicin and cisplatin (MAP) and subsequent maintenance with weekly 5-FU and leucovorin (FL) were designed with an aim to reduce acute and chronic toxicity of PF. Thirty-two patients of NPC with measurable metastatic lesions in the liver or lung were entered into this phase II trial. Mitomycin C 8 mg m(-2), doxorubicin 40 mg m(-2) and cisplatin 60 mg m(-2) were given on day 1 every 3 weeks as initial induction. After either four courses or remission was achieved, patients received weekly dose of 5-FU 450 mg m(-2) and leucovorin 30 mg m(-2) for maintenance until disease progression. With 105 courses of MAP given, 5% were accompanied by grade 3 and 0% were accompanied by grade 4 stomatitis. The dose-limiting toxicity of MAP was myelosuppression. Forty per cent of courses had grade 3 and 13% of courses had grade 4 leukopenia. No grade 3 or 4 cisplatin-related toxicity was observed. The overall response rate was 94% (95% confidence interval (CI) 84.9-100%) with a complete response rate (CR) of 6% (95% CI: 0-15.2%) and a good partial response (PR) rate of 28% (95% CI 11.7-44.6%), which was optionally defined as observance of only equivocal lesion identifiable under imaging study. Twenty-seven cases entered weekly FL maintenance phase. The median duration of maintenance with weekly FL was 38 weeks (8-91 weeks). There was no grade 3 or 4 toxicity noted during weekly FL. The median progression-free survival and overall survival were 11.6+/-0.4 and 18.1+/-3.6 months respectively. Six patients with a median follow-up of 19.8 months (9.6-41.0 months) were still alive and five of them had disease under control with FL. Good responders (CR and good PR) had better survival than less satisfactory responders (PR and stable disease) (P = 0.05). From Cox's multivariate regression analysis, the only significant prognostic factor for survival was good response to MAP (P = 0.042). Liver metastasis was the only significant variable in the best subset regression model that predicted good response to MAP (CR and good PR) (P = 0.027). MAP was an effective combination for metastatic NPC with minimal stomatitis and cisplatin-related toxicity but had significant myelosuppression. Weekly FL was a maintenance therapy with minimal side-effects. The response rate and overall survival of MAP-FL were better than series previously reported even when a subset of patients with poor prognosis was selected. MAP-FL's role as neoadjuvant or adjuvant therapy is worthy of further study.

Adult↗
PubMed1999

Epstein-Barr virus-encoded latent membrane protein 1 co-expresses with epidermal growth factor receptor in nasopharyngeal carcinoma.

Latent membrane protein 1 (LMP-1) is the only Epstein-Barr virus (EBV)-encoded oncogenic protein that has been detected in nasopharyngeal carcinoma (NPC), a cancer that is closely associated with EBV. Previous in-vitro studies have demonstrated that LMP-1 can upregulate epidermal growth factor receptor (EGFR) in epithelial cells. It was not established whether this cellular effect exists in NPC. To assess the association between LMP-1 and EGFR in NPC tissues, 60 NPC specimens were examined by immunohistochemistry using anti-LMP-1 antibody (CS 1-4) and anti-EGFR antibodies (EGFR 1, EGFR 1005). The results revealed that 41 (68.3%) specimens were immunopositive for LMP-1 and 44 (73.3%) specimens over-expressed EGFR. Morphologically, the expressions of LMP-1 and EGFR were homogeneously distributed in the tumor nests. In addition, the correlation between LMP-1 and EGFR was statistically significant (P<0.001, chi2 test, d.f. = 1). To elucidate further the correlation between LMP-1 and EGFR in vivo and in situ, an indirect dual immunofluorescence assay was conducted, using secondary antibodies conjugated with fluorescein isothiocyanate (FITC) or indocarbocyanine (Cy3). The results disclosed an intimate co-expression of LMP-1 and EGFR. In summary, the data indicate that over-expression of EGFR is a common phenomenon in NPC, and that EGFR is co-expressed with LMP-1 in NPC. Thus, EBV may play a role in the tumorigenesis of NPC through the effects of LMP-1 and EGFR.

ErbB Receptors↗
PubMed1999

Chromosomal aberrations in nasopharyngeal carcinoma analyzed by comparative genomic hybridization.

To investigate the genomic imbalances associated with nasopharyngeal carcinoma (NPC), we have performed chromosome analysis by comparative genomic hybridization (CGH) on 51 tumors, including 25 primary and 26 recurrent tumors. The most common copy number increases occurred on chromosome arms 12p (59%), 1q (47%), 17q (47%), 11q (41%), and 12q (35%). The minimal overlapping regions were at 12p12-13, 1q21-22, 17q21, 17q25, 11q13, and 12q13. The most frequent losses were from chromosome arms 3p (53%), 9p (41%), 13q (41%), 14q (35%), and 11q (29%). The minimal overlapping regions were at 3p12-14, 3p25-26, 9p21-23, 13q21-32, 14q12-21, and 11q14-23. Compared with the primary cancers, no additional chromosomal change was found in the recurrent tumors; however, the most frequent gain in the recurrent NPCs was at 11q13 (53%) instead of 12p in the primary tumors. An increase of gene alterations correlated with clinical stage. Our results provide a first comprehensive view of the genomic changes associated with NPC and reveal several new sites of genomic imbalance, indicating the possible involvement of novel oncogenes/tumor suppressor genes in the carcinogenesis of NPC.

Adult↗
PubMed1998

Increased mutagen sensitivity in patients with head and neck cancer is less pronounced in patients with nasopharyngeal carcinoma.

BACKGROUND: Mutagen sensitivity tested with bleomycin sulfate can determine a susceptible phenotype, which is relevant only in organs and tissues that have direct contact with the external environment. Patients with head and neck cancers have more mutagen sensitivity than control subjects without cancer, and the hypersensitive phenotype has a risk for the development of a second primary cancer. Head and neck cancers, however, represent a heterogeneous group of neoplasm. The biological behavior of nasopharyngeal carcinoma (NPC) and other head and neck cancers differs. OBJECTIVE: To evaluate the difference in mutagen sensitivity among patients without cancer, patients with NPC, patients with oral or oropharyngeal cancer (ORC), and patients with laryngeal or hypopharyngeal cancer (LHC). DESIGN: Peripheral blood was cultured at 37 degrees C, using 5% carbon dioxide, for 72 hours. After 67 hours of incubation, bleomycin in a concentration of 30 IU/L was added to induce chromatid breaks. The number of chromatid breaks per cell was scored in 50 metaphases of cultured lymphocytes and compared in the 4 groups. SUBJECTS: Patients with histologically proven squamous cell carcinoma of the mucosa of the upper digestive tract, which included 3 groups: patients with NPC, patients with ORC, and those with LHC. Control subjects were hospital inpatients with no tumor history. There were 35 patients in each group. RESULTS: The mean (+/-SD) number of breaks per cell in the control group and in the groups with NPC, ORC, and LHC were 0.80 (+/-0.32), 1.03 (+/-0.45), 1.30 (+/-0.44), and 1.35 (+/-0.46), respectively. All the cancer groups had significantly higher mean breaks per cell and a higher prevalence of hypersensitivity than the control group. Patients with NPC had a significantly lower mean number of breaks per cell than the group with ORC or that with LHC. CONCLUSIONS: Patients with NPC had less mutagen sensitivity than those with ORC or LHC. Our results support the clinical and epidemiological findings of a difference between NPC and other head and neck cancers. Environmental factors might play a less pronounced role in the carcinogenesis of NPC.

Adult↗
PubMed1998

Nasopharyngeal swab and PCR for the screening of nasopharyngeal carcinoma in the endemic area: a good supplement to the serologic screening.

BACKGROUND: Nasopharyngeal carcinoma (NPC) is a common head and neck cancer in Taiwan. Early detection is the best way to improve survival for this disease. A prospective study was designed to assess the feasibility of a new screening method for NPC by use of polymerase chain reaction (PCR) based on the close association of NPC and Epstein-Barr virus (EBV). METHODS: One hundred thirty-three different tissues from nasopharynx, nose, and sinus were investigated by use of PCR to check for the presence of EBV genome. Subsequently, from April 1996 to March 1997, 55 patients were enrolled in a prospective screening study. All patients underwent nasopharyngeal swabs before biopsy. Polymerase chain reaction detection of EBV genome was conducted on swab samples. Anti-EBV viral capsid antigen (VCA) in IgA and IgG class were checked at the same visit. RESULTS: The EBV genome was present in 91.4% (85/93) of NPC tissues and in 25.0% (10/40) of non-NPC tissues (p < .001, chi2 test). Of the 55 swabs, 49 (89.1%) specimens obtained enough cells for PCR examination. Thirty of these 49 patients were pathologically proved NPC. The presence of EBV were 86.7% (26/30) in NPC group and 42.1% (8/19) in non-NPC group. The sensitivity and specificity were 86.7% and 57.9%, respectively, which were similar to those of serologic method (87.5% and 43.5%) when the cut-off point was set at anti-VCA IgG > or = 160 and IgA > or = 10. Combining both methods elevates the specificity to 84.2%. CONCLUSIONS: The sensitivity of this PCR screening method is similar to that of the serologic method. Combining both methods can greatly increase the specificity, indicating this new method is a good supplement to the serologic screening of this endemic disease.

Antibodies, Viral↗
PubMed1998

Partial vertical laryngectomy in the treatment of early glottic cancer.

Treatment of early glottic cancer is still controversial. A retrospective study was conducted to analyze the results of 49 partial vertical laryngectomies in our department. All patients except 1 were successfully decannulated. The quality of voice was suboptimal but serviceable in all patients. Overall, there were 9 recurrences: 7 in the larynx and 2 in the neck. In the laryngeal recurrence group, 5 of 6 patients were successfully salvaged with total laryngectomy. One patient died of acute renal failure 1 month after salvage operation. Another patient survived 4.5 years after cisplatin-based chemotherapy. In the neck recurrence group, 1 patient was successfully salvaged with neck dissection; the other was lost to follow-up after neck dissection. The actuarial 5-year survival rate was 97.4% and the larynx preservation rate was 88%. The recurrence rate was 14%, when 2 of the 7 laryngeal recurrences were excluded because they occurred beyond 5 years. The results of this series were encouraging. We suggest that partial vertical laryngectomy is a good treatment modality for selected early glottic cancers, especially those of the T1 group.

Adult↗
PubMed1998

Contracture of the deltoid muscle. Results of distal release.

We prospectively studied the results of distal release, performed between February 1989 and December 1994 for the treatment of a contracture of the deltoid muscle, in forty patients (forty-nine shoulders). Forty-seven contractures (in thirty-eight patients) developed after multiple intramuscular injections of various medications. The two remaining contractures (in two patients) were congenital. The average age at the onset of the symptoms was thirty-two years (range, birth to fifty-eight years). The primary symptoms included pain around the neck and the shoulder girdle, dimpling of the skin, a palpable fibrous band, winging of the scapula, difficulty in combing the hair or reaching the contralateral side of the body for grooming, and inability to bring the arm adjacent to the body. The average age at the time of the operation was thirty-nine years (range, fifteen to sixty-three years). The average duration of follow-up was three years and eleven months (range, two years to six years and six months). After the distal release of the contracture, but on the same day, the patients started a physical-therapy program. Postoperatively, the pain, dimpling of the skin, palpable fibrous band, and winging of the scapula resolved in forty-eight shoulders (thirty-nine patients). Six patients (six shoulders) no longer had difficulty in combing the hair or adducting the shoulder. There were no infections or neuromuscular complications. Forty-seven (96 per cent) of the forty-nine shoulders (thirty-eight of the forty patients) had a good clinical result, and two shoulders (two patients) had a poor result. Anterosuperior subluxation of the humeral head, noted on preoperative radiographs of twenty-three shoulders (eighteen patients), was not present postoperatively. Drooping of the acromion, seen in six patients (six shoulders) in whom the contracture had developed before they were sixteen years old, improved postoperatively in five shoulders (five patients). Rotation of the scapula, seen in five shoulders (five patients), resolved after release of the contracture in all five. There were no clinical or radiographic signs of osteoarthrosis due to long-term anterior translation of the shoulder joint in the four patients (six shoulders) who had had the contracture for at least twenty years (average, twenty-three years; maximum, twenty-seven years).

Adolescent↗
PubMed1998

Usefulness of Doppler spectral analysis and power Doppler sonography in the differentiation of cervical lymphadenopathies.

OBJECTIVE: Our purpose was to depict the characteristics of the global vasculature of cervical lymphadenopathies and to clarify the efficiency of Doppler spectral analysis and power Doppler sonography in the differential diagnosis. SUBJECTS AND METHODS: Prospectively, 289 lymph node lesions underwent Doppler flow studies and were grouped as metastasis, lymphoma, tuberculosis, and benign lymphadenopathies. Sonographic assessments included vascular pattern and vascular density (presented as vascularity index) as revealed by power Doppler sonography. Vascular resistive index and pulsatility index were assessed by at least three flow samplings. Values of both the highest and the lowest resistance were analyzed. Vascularity index, resistive index, pulsatility index, nodal size, and age were correlated. RESULTS: Most benign lymphadenopathies (87%), tuberculous lymphadenopathies (72%), and lymphomas (71%) revealed an avascular or hilar vascular pattern. Vascular patterns of most metastatic lymphadenopathies (90%) were of spotted (26%), peripheral (11%), or mixed (53%) type. The vascularity indexes of metastatic lymphadenopathy (mean, 0.176) and lymphoma (mean, 0.122) were significantly higher than those of tuberculous and benign lymphadenopathy (mean, 0.054 and 0.042, respectively). In vascular resistance studies, the highest pulsatility index and resistive index in metastatic lymphadenopathy statistically exceeded those of benign lymphadenopathy, whereas no difference was found in the lowest values. Negative correlation was found between the vascularity index of metastatic lesions and their lowest vascular resistance, and positive correlation was found between vascularity index and nodal size in benign lymphadenopathies. CONCLUSION: In addition to vascular resistance assessed traditionally with Doppler spectral analysis, vascular pattern and vascular density assessed with power Doppler sonography can better differentiate the nature of lymphadenopathies.

Adolescent↗
PubMed1998

Intraluminal involvement of thyroid cancer in the trachea.

Invasion of the air passage, especially with intraluminal involvement of well-differentiated thyroid carcinoma, is rare. Establishing a patent airway before surgery is necessary, but difficult and risky. We report a case of thyroid cancer with intraluminal invasion of the trachea. A 62-year-old schizophrenic woman presented with blood-tinged sputum and dyspnea. She had undergone a thyroid lobectomy 8 years previously. Computed tomography and bronchoscopy showed a protruding mass in the upper trachea and limited movement of the bilateral vocal folds. Emergency tracheostomy was performed to relieve impending apnea. Fine-needle aspiration of the left protruding thyroid gland showed papillary carcinoma. Because the tumor diffusely infiltrated the thyroid gland and intermingled with fibrosis due to the previous thyroid operation, and because there was limited movement of bilateral vocal folds, the patient underwent total laryngectomy, total thyroidectomy, total parathyroidectomy, and tracheal resection. Neither radioactive iodine nor external irradiation were given because of anticipated poor compliance due to schizophrenia. The postoperative course was smooth and thyroid hormone and calcium were supplemented regularly. The patient has lived well and without local recurrence for more than 3 years since the operation. She can speak with an artificial larynx.

Carcinoma, Papillary↗
PubMed1998

Reconstruction of circumferential pharyngeal defect following cancer surgery with tubed pectoralis major myocutaneous flap and interdigitating anastomosis.

Hypopharyngeal cancer has a poor prognosis and the tumor may spread submucosally to involve all the pharyngeal mucosa. Reconstruction of circumferential defects after resection of hypopharyngeal cancer is a challenge. We describe our results using a tubed fan-shaped pectoralis major myocutaneous flap and distal interdigitating anastomosis to reconstruct a circumferential pharyngeal defect following surgical resection in six patients with advanced hypopharyngeal cancer. There was no perioperative mortality in this study. Fistula formation occurred in three patients and was corrected by secondary closure in two and spontaneous healing in one. Oral intake was started 2 weeks to 2 months after surgery. Four patients died of distant metastases within 24 months of follow-up and two survived without disease. Neither locoregional recurrence nor stenosis occurred. Our results show that the tubed fan-shaped pectoralis major myocutaneous flap with distal interdigitating anastomosis is a reliable way to reconstruct circumferential pharyngeal defects, and is relatively noninvasive.

Adult↗
PubMed1998

Nasopharyngeal angiofibroma: a reappraisal of clinical features and treatment at National Taiwan University Hospital.

Nasopharyngeal angiofibroma (NAF), occurring mostly in young men, is a histologically benign tumor with aggressive clinical behavior that includes repeated epistaxis and intractable nasal obstruction. This paper reviews our recent experience at National Taiwan University Hospital (NTUH), and compares the results with those of a previous study (1955-1980) at NTUH to highlight the developments in the treatment of NAF. Fifteen patients with a diagnosis of NAF from 1984 to 1997 were included, and their clinical presentations, radiographic studies, treatments, and outcomes were retrospectively analyzed. The results showed that the clinical and demographic features were similar in the two studies. The average number of patients decreased from 2.1 patients in the previous study to 1.1 patients in this study. The duration of symptoms in the current study (8 months) was shorter than that of the previous study (16 months). Previously, the treatment consisted of radiation followed by surgery if there was residual tumor. The current treatment modality is preoperative transarterial embolization followed by surgery. The estimated intraoperative blood loss was reduced from 750 mL in the first study to 400 mL in this study. The recurrence rate decreased from 11% to 7% and the absolute relapse-free rate rose from 56% to 73%. Owing to the development of modern imaging techniques, the advent of preoperative arterial embolization, and advances in surgical techniques, successful removal of highly vascular tumors has become more feasible. Preoperative selective embolization followed by excision is an effective treatment modality. This strategy, an alternative to radiotherapy, not only avoids the long-term complications induced by radiation, but also reduces the tumor recurrence rate.

Adolescent↗
PubMed1997

Undifferentiated carcinoma of the major salivary glands.

BACKGROUND: Undifferentiated carcinoma of the salivary glands is a rare disease, the incidence of which is highest among the Inuit of Greenland and North America. It was demonstrated to be closely related to Epstein- Barr virus (EBV) infection. However, the relation of EBV to this tumor has not been studied to any great extent here in Taiwan because of the small number of cases. METHODS: Twelve cases of undifferentiated carcinoma of the salivary glands from the period 1977-1996 were retrieved from the cancer registry at National Taiwan University Hospital. The clinical data were analyzed retrospectively based on the medical records. Eleven formalin fixed, paraffin embedded tissue sections were used for in situ hybridization with an antisense probe complementary to EBV-encoded RNA 1 (EBER1). RESULTS: Ten of 12 tumors originated from the parotid gland and 2 from the submandibular gland. The patients' ages ranged from 22 to 63 years, with an average of 38.1 years. One patient was lost to follow-up, 2 patients died of metastatic disease, and the remaining 9 patients were all alive and disease free at last follow-up. The actuarial 5-year survival rate was 79.8%. In situ hybridization demonstrated EBER1 in 9 of the undifferentiated carcinomas with lymphoid stroma, but EBER1 was not demonstrated in the other 2 tumors without lymphoid stroma. CONCLUSIONS: Undifferentiated carcinoma with lymphoid stroma of the major salivary glands is closely associated with EBV. The mainstay of treatment is surgery and postoperative radiotherapy. The outcomes in this series were good except for two elderly patients who died of rapid and progressive distant metastases.

Adult↗