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Tak Wai Lee

Publications and source records attributed to Tak Wai Lee.

At least 19 recordsLinked to original sources
PubMed2006

Video-assisted thoracic surgery lobectomy for lung cancer is associated with less immunochemokine disturbances than thoracotomy.

OBJECTIVE: Major surgery is immunosuppressive and could have an impact on postoperative tumor immunosurveillance and recurrence in cancer patients. Low circulating levels of insulin growth factor binding protein (IGFBP)-3 have been linked to advance prostate and the development of colonic cancers. This prospective study examined the early postoperative circulating levels of IGFBP-3, matrix metalloproteinase (MMP)-9, and tissue inhibitor of metalloproteinase (TIMP)-1 in early stage non-small cell lung cancer (NSCLC) patients undergoing major lung resection by VATS versus thoracotomy. METHODS: Forty-two consecutive patients with resectable primary NSCLC were assigned to VATS or thoracotomy approach over a 7-month-period. Blood samples were collected preoperatively and postoperatively on days (POD) 1 and 3 for enzyme linked immunosorbent assay determination of IGFBP-3, MMP-9 and TIMP-1 levels in the serum. RESULTS: There were no demographic differences between the two groups. VATS lung resection was associated with lower levels of MMP-9 and TIMP-1 on POD1 (median 628 vs 1311ng/ml, p=0.009; and 131 vs 211ng/ml, p=0.004, respectively) but higher levels of IGFBP-3 on POD3 (1366 vs 1144ng/ml, p=0.02), when compared with the thoracotomy approach. There was no perioperative mortality. CONCLUSIONS: VATS major lung resection for NSCLC is associated with higher circulating levels of IGFBP-3, and lower levels of MMP-9 and TIMP-1, compared to the thoracotomy approach. The clinical relevance of these postoperative changes on tumor biology following lung resection for cancer warrants further investigation.

Aged↗
PubMed2006

Bronchiolitis obliterans following lung transplantation.

Bronchiolitis obliterans syndrome (BOS) is the main and late chronic complication after lung transplantation. It remains a major impediment to long-term outcome. Unfortunately, the survival rate of lung transplant recipients lags behind that of other organ transplant recipients, and BOS accounts for more than 30% of all mortality after the third year following lung transplantation. Most recent studies suggest that immune injury is the main pathogenic event in small airway obliteration and the development of BOS. Early detection of BOS is possible as well as essential because prompt initiation of treatment may halt the progress of the disease and the development of chronic graft failure. Current treatment of BOS is disappointing despite advances in surgical techniques and improvements in immunosuppressive therapies. Therefore, a clear understanding of the pathogenesis of BOS plays a major role in the search for new and effective therapeutic strategies for better long-term survival and quality of life after lung transplantation.

Bronchiolitis Obliterans↗
PubMed2006

Analgesic effect of electroacupuncture in postthoracotomy pain: a prospective randomized trial.

BACKGROUND: The role of electroacupuncture in postthoracotomy pain control is uncertain. We conducted a pilot study to evaluate the role of electroacupuncture in the management of early postthoracotomy wound pain. METHODS: A total of 27 patients with operable non-small cell lung carcinoma who received thoracotomy were recruited and randomized to receive either electroacupuncture or sham acupuncture in addition to routine oral analgesics and patient-controlled intravenous analgesia for postoperative pain control. All patients received acupuncture twice daily with visual analog pain score recorded for the first 7 postoperative days. Specific chest acupoints (LI 4, GB 34, GB 36, and TE 8) were targeted. Patient-controlled analgesia was used for the first 3 postoperative days in all patients, and the cumulative dosage used was recorded. RESULTS: Two patients were excluded after randomization because of complications unrelated to acupuncture. Interventions and data collection were completed for the remaining 25 patients (13 in the electroacupuncture group; 12 in the sham acupuncture group). There was a trend for lower visual analog scale pain scores in the electro-acupuncture group between postoperative days 2 and 6, although this did not reach statistical significance. The cumulative dose of patient-controlled analgesia morphine used on postoperative day 2 was significantly lower in the electroacupuncture group (7.5 +/- 5 mg versus 15.6 +/- 12 mg; p < 0.05). Such delay of onset of pain control may be related to the frequency of electroacupuncture used. CONCLUSIONS: Electroacupuncture may reduce narcotic analgesic usage in the early postoperative period. A prospective randomized controlled trial using different electroacupuncture frequency is warranted to verify this benefit.

Acetaminophen↗
PubMed2006

Video-assisted thoracic surgery pulmonary resection for lung cancer in patients with poor lung function.

BACKGROUND: The aim of this study is to evaluate the early outcome of patients with poor lung function who underwent video-assisted thoracic surgery (VATS) pulmonary resection for primary non-small cell lung carcinoma. METHODS: We reviewed retrospectively the records of patients with lung cancer undergoing VATS lung resection over a period of 5 years. Twenty-five patients with preoperative poor lung function defined as forced expiratory volume in 1 second less than 0.8 L or the percentage predicted value for forced expiratory volume in 1 second less than 50% were identified. Thirteen patients underwent VATS lobectomies and 12 VATS wedge resections. Data were analyzed with respect to demographics, risk factors, and early postoperative outcome and survival. RESULTS: There were 8 cases of morbidities (29%) and no surgical mortality. Five of these 8 patients had respiratory-related complications after surgery. A deterioration in pulmonary performance as indicated by the Eastern Cooperative Oncology Group (ECOG) score was seen in 7 patients (28%), with only 1 patient having an ECOG score greater than 2. No patient required home oxygen supplementation beyond the third month postoperatively. After a median follow-up period of 15.1 months (range, 1 to 24), 5 patients died. Only 1 patient (4%) died of a respiratory complication (pneumonia 6 weeks after surgery). The other 4 deaths were due to recurrent or metastatic disease. The actuarial survival rates at 1 and 2 years were 80% and 69%, respectively. CONCLUSIONS: Video-assisted thoracic surgery pulmonary resection for cancer in patients with poor lung function can achieve acceptable functional and oncologic outcome.

Aged↗
PubMed2006

Video-assisted thoracic surgery for early stage lung cancer - can short-term immunological advantages improve long-term survival?

The development of video-assisted thoracic surgery (VATS) in the past decade has changed the way many pulmonary conditions are being treated. VATS has gained popularity among clinicians due to faster recovery following surgery, less postoperative pain and better cosmesis. It is well known that surgical trauma can induce a systemic inflammatory response and affect postoperative systemic immunity. Minimal access VATS has been shown to be associated with a reduced postoperative systemic inflammatory response. Recent evidence suggests VATS is also associated with better cellular immunity, and produces less immunochemokine disturbance following surgery, when compared with the thoracotomy approach. Circulating natural killer (NK) cell numbers and levels of insulin growth factor binding protein (IGFBP) are found to be higher, and plasma levels of matrix metalloproteinases are lower following VATS than that after thoracotomy. Maintenance of immune function with VATS may have important clinical implications in lung cancer surgery.

Follow-Up Studies↗
PubMed2005

Post-pneumonectomy empyema: current management strategies.

Post-pneumonectomy empyema is an uncommon but potentially life-threatening complication. It has a strong association with bronchopleural fistula, which acts as a continued source of infection into the thoracic cavity. Numerous risk factors have been identified and strategies formulated to minimize its occurrence. When bronchopleural fistula occurs, its treatment depends on several factors including extent of dehiscence, degree of pleural contamination and general condition of the patient. Early diagnosis and assessment with appropriate investigations, and aggressive therapeutic strategies are paramount in controlling sepsis, facilitating closure of fistula, and sterilization of the closed pleural space. Recent success with repeat debridement has made routine space obliteration not mandatory in management. The development of minimal-access interventions including video-assisted thoracic surgery, endoscopic application of tissue glue and stenting may be additional tools to complement conventional surgery in post-pneumonectomy empyema management.

Bronchial Fistula↗
PubMed2005

Video-assisted thoracic surgery thymectomy for nonthymomatous myasthenia gravis.

STUDY OBJECTIVES: Minimal-access thymectomy has become increasingly popular as surgical treatment for patients with nonthymomatous myasthenia gravis (NTMG) because of its comparable efficacy, safety, and lesser degree of tissue trauma compared with conventional open surgery. We reviewed and analyzed our data on video-assisted thoracic surgery (VATS) thymectomy and present the clinical outcomes according to the Myasthenia Gravis Foundation of America classification. DESIGN: A retrospective review of VATS thymectomy for NTMG in a university hospital over a 12-year period. Data were collected from the medical records and supplemented with telephone surveys. The impact of surgery and other variables potentially affecting complete stable remission (CSR) were calculated using Kaplan-Meier survival curves; comparisons between survival curves was performed using the log-rank test. RESULTS: A total of 38 consecutive patients underwent VATS thymectomy for NTMG. Median postoperative stay was 3 days. Pathologic examination revealed thymic hyperplasia in 61.1% of cases, normal thymus in 22.2%, and thymic atrophy in 16.6%. There was no perioperative mortality; complications occurred in four patients. After a median follow-up of 69 months, 91.6% of patients experienced improvement, with crude CSR achieved in 22.2%. Kaplan-Meier survival curve demonstrated a 75% CSR rate at 10-year follow-up. On univariate analysis, only disease duration < or = 12 months (p = 0.03) was associated with a statistically significant improvement in CSR. CONCLUSIONS: VATS thymectomy for NTMG results in symptomatic improvement in the vast majority of patients, with a high rate of CSR. The procedure is associated with low morbidity and no perioperative mortality. Future studies on thymectomy for myasthenia gravis should be reported in a standardized manner to allow accurate comparisons between results in the absence of randomized prospective trials.

Adult↗
PubMed2004

Should cervical ultrasonography be a routine staging investigation for lung cancer patients with impalpable cervical lymph nodes?

OBJECTIVES: Detection of cervical N3 lymph nodes is currently not a routine preoperative investigation for lung cancer patients. We designed a study to assess if the frequency and accuracy of detection of metastatic cervical lymph nodes using cervical ultrasonography (US) and fine needle aspiration (FNA) justify their routine use in all lung cancer patients with impalpable cervical lymph nodes. METHODS: Fifty patients with suspected and potentially operable non-small cell lung cancer were enrolled. Patients with palpable cervical lymph nodes were excluded. In addition to routine preoperative investigations, all patients received cervical US to determine the presence of cervical lymph nodes. Nodes suspicious of harboring malignancy according to a specific set of sonographic criteria (which include shape, echogenicity, nodal architecture, and vascular patterns) were subjected to biopsy by ultrasound-guided FNA. RESULTS: Normal cervical lymph nodes were detected by cervical US in 30 patients (60%). Cervical lymph nodes suspicious of harboring malignancy were detected in 10 patients (20%). FNA confirmed cervical nodal metastasis in four of these patients (8%). The TNM staging of two patients (4%) was revised up to stage IIIb as a result, excluding them from further surgery. Cost analysis suggests this technique to be cost-effective when used as a routine preoperative investigation to exclude patients from unnecessary surgical intervention. No mortality or complications were encountered in all patients. CONCLUSIONS: Cervical US and FNA is a safe and cost-effective method of evaluating the status of impalpable cervical lymph nodes in lung cancer patients. Further study is warranted to establish the role of cervical US and FNA in lung cancer staging algorithms.

Adult↗
PubMed2004

Video-assisted thoracic surgery for primary spontaneous hemopneumothorax.

OBJECTIVE: Video-assisted thoracic surgery (VATS) has changed the way we manage a number of thoracic conditions. This study presents near over a decade of experience from our institution on management of spontaneous hemopneumothorax (SHP), with particular reference to the use of VATS. METHODS: Retrospective review between March 1988 and December 2002 with 793 patients treated for spontaneous pneumothorax, 30 (3.8%) patients had SHP. The clinical features, indications for surgery and outcomes are discussed. RESULTS: All 30 SHP patients were male with mean age of 25 years. Signs of significant hypovolemia occurred in 4 patients, 3 required blood transfusion. Mean initial blood drainage from tube thoracostomy was 594 ml. All SHP patients received surgery (5 thoracotomies, 25 VATS). Active bleeding was identified in 16 patients; 12 from torn apical vascular adhesion band and 4 from vascular bleb. Postoperative complications after thoracotomy include 2 chest infections and 1 air leak, while VATS had 1 chest infection and 1 air leak (P=0.022). Mean postoperative hospital stay following VATS was 3.9 days and thoracotomy 7.5 days (P=0.0021). There is no recurrence of pneumothorax or SHP during mean follow-up of 21 months. CONCLUSION: SHP can be life threatening and is a cause for patients presenting with unexplained signs of significant hypovolemia. Surgery in the form of VATS should be considered early in the management of SHP, with potentially less postoperative complications and shorter postoperative hospital stay compared with open thoracotomy.

Adolescent↗
PubMed2004

Early results of endoscopic lung volume reduction for emphysema.

BACKGROUND: We determined the feasibility, safety, and short-term efficacy of bronchoscopic placement of a one-way endobronchial valve in selected bronchopulmonary segments as an alternative to surgical lung volume reduction. METHODS: A total of 21 patients with incapacitating emphysema who underwent this procedure were studied. All patients had placement of the endobronchial valves into the most emphysematous lung segments. We recorded any major complications or deaths attributed to the procedure and analyzed (1) improvements in the spirometric and functional parameters and quality of life and (2) the radiologic changes compared with the baseline data at 30 and 90 days. RESULTS: A total of 20 patients had complete follow-up data. There was no mortality in the group studied. The forced expiratory volume at 1 second, forced expiratory volume at 1 second (percentage of predicted), forced vital capacity, and forced vital capacity (percentage of predicted) all improved significantly at 90 days (0.73 +/- 0.26 L vs 0.92 +/- 0.34 L [P =.009]; 33.3% +/- 11.9% vs 42.2% +/- 15.0% [P =.006]; 1.94 +/- 0.62 L vs 2.25 +/- 0.61 L [P =.015]; and 63.3% +/- 17.6% vs 73.9% +/- 17.1% [P =.012], respectively). The 6-minute walking distance improved at 30 and 90 days (251.6 +/- 100.2 m vs 306.3 +/- 112.3 m and 322.3 +/- 129.7 m; P =.012 and P =.003). The results of the 36-Item Short-Form Health Survey and the St George Respiratory Questionnaire showed significant improvements at 90 days. The Medical Research Council dyspnea grade also improved significantly at 30 and at 90 days (P =.006 and P =.003, respectively). CONCLUSIONS: Endobronchial valve placement is a safe procedure, with significant short-term improvements in functional status, quality of life, and relief of dyspnea in selected patients with emphysema. A larger study with long-term follow-up is therefore warranted.

Adult↗
PubMed2004

Selective lobar collapse for video-assisted thoracic surgery.

BACKGROUND: Video-assisted thoracic surgery (VATS) is conventionally performed under single-lung ventilation. A small proportion of patients are often excluded from undergoing VATS because of their inability to tolerate single-lung ventilation. We describe a simple technique of selective lobar lung collapse that may help to recruit additional, selected patients for VATS. METHODS: We use a standard suction catheter placed under bronchoscopic guidance to the target lobar bronchus through a single-lumen endotracheal tube. The catheter is left open to air, or suction can be applied to facilitate lobar collapse. The remaining lobe of the same lung can be ventilated throughout surgery. Surgery is performed using standard VATS techniques. RESULTS: Using this technique we have successfully performed VATS on 63 chest sides in 35 patients. The procedures performed included thoracodorsal sympathectomies (n = 28), mechanical pleurodesis procedures (n = 3), mediastinal and pleural biopsies (n = 2), and lung wedge resections (n = 2). We encountered no mortality or morbidity in all cases. CONCLUSIONS: This technique is simple and safe and requires no expensive disposable devices. Although not essential for most patients undergoing VATS, it deserves to be in the armamentarium of the thoracic surgeon. Further studies will be required to better define its application in clinical practice.

Adult↗
PubMed2003

Hemoptysis from an unusual pulmonary arteriovenous malformation.

We report the case of a 64-year-old woman who presented with massive hemoptysis. She was found to be bleeding from a pulmonary arteriovenous malformation in the right middle lobe, which had a peculiar blood supply from the right internal mammary artery. Video-assisted thoracic surgery lobectomy was successfully performed for this condition. Limitations of embolization as a treatment modality for this condition are discussed.

Angiography↗
PubMed2003

Continuous thoracic paravertebral infusion of bupivacaine for pain management in patients with multiple fractured ribs.

STUDY OBJECTIVE: To evaluate the efficacy of a continuous thoracic paravertebral infusion of bupivacaine for pain management in patients with unilateral multiple fractured ribs (MFR). DESIGN: Prospective nonrandomized case series. SETTING: Multidisciplinary tertiary hospital. PATIENTS: Fifteen patients with unilateral MFR. INTERVENTIONS: Insertion of a catheter into the thoracic paravertebral space. We administered an initial injection of 0.3 mL/kg (1.5 mg/kg) bupivacaine 0.5% with 1:200,000 epinephrine followed 30 min later by an infusion of bupivacaine 0.25% at 0.1 to 0.2 mL/kg/h for 4 days. MEASUREMENTS AND RESULTS: The following parameters were measured during the initial assessment before thoracic paravertebral block (TPVB), 30 min after the initial injection, and during follow-up on day 1 and day 4 after commencing the infusion of bupivacaine: visual analog pain score at rest and during coughing; respiratory rate; arterial oxygen saturation (SaO(2)); bedside spirometry (ie, FVC, FEV(1), FEV(1)/FVC ratio, and peak expiratory flow rate [PEFR]); arterial blood gas measurements; and O(2) index (ie, PaO(2)/fraction of inspired oxygen ratio). There were significant improvements in pain scores (at rest, p = 0.002; during coughing, p = 0.001), respiratory rate (p < 0.0001), FVC (p = 0.007), PEFR (p = 0.01), SaO(2) (p = 0.04), and O(2) index (p = 0.01) 30 min after the initial injection, which were sustained for the 4 days that the thoracic paravertebral infusion was in use (p < 0.05). PaCO(2) did not change significantly after the initial injection, but on day 4 it was significantly lower than the post-TPVB value (p = 0.04). One patient had an inadvertent epidural injection, and another developed transient ipsilateral Horner syndrome with sensory changes in the arm. No patient exhibited clinical signs of inadvertent intravascular injection or local anesthetic toxicity. CONCLUSION: Our results confirmed that continuous thoracic paravertebral infusion of bupivacaine is a simple and effective method of providing continuous pain relief in patients with unilateral MFR. It also produced a sustained improvement in respiratory parameters and oxygenation.

Adult↗
PubMed2002

A Phase I-II study of sequential administration of topotecan and oral etoposide (toposiomerase I and II inhibitors) in the treatment of patients with small cell lung carcinoma.

BACKGROUND: Topotecan (9-dimethylaminomethyl-10-hydroxycampthothecin) is a new topoisomerase I inhibitor with promising efficacy in the treatment of patients with small cell lung carcinoma (SCLC). Combination with a topoisomerase II inhibitor may potentate the therapeutic effect of topotecan, although there has been conflicting preclinical information on the combination. The objectives of this study were to establish the maximum tolerated dose and to determine the efficacy of the sequential combination of intravenous topotecan and oral etoposide in the treatment of patients with SCLC. METHODS: Patients with histologically confirmed, limited or extensive stage SCLC were eligible. The dose escalation scheme of three cohorts (six patients per cohort) started at intravenous topotecan 0.5 mg/m(2) per day for 5 days and oral etoposide 50 mg twice daily for 7 days (21-day cycles). Subsequent dose levels involved escalation of topotecan to 0.75 mg/m(2) per day and 1.0 mg/m(2) per day for 5 days. A Phase II study was conducted at one dose level below the maximum tolerated dose. The authors alternated the drug sequence with each consecutive cycle and compared the hematologic toxicity between the two sequences. RESULTS: Thirty-six patients (21 patients with limited disease and 15 patients with extensive disease) received a total of 173 courses of sequential combination chemotherapy (topotecan --> etoposide, 88 courses; etoposide --> topotecan, 85 courses). The authors identified dose levels for the Phase II study as follows: topotecan, 0.75 mg/m(2) per day for 5 days; and etoposide, 50 mg twice daily for 7 days. The dose-limiting toxicity was neutropenia. At this dose level, the incidence of Grade 3-4 neutropenia and the incidence of Grade 3-4 thrombocytopenia were 25% and 10.9%, respectively. Two patients died from neutropenic sepsis. There was no significant difference in hematologic toxicities between the two sequences. Complete and partial response rates were 5.6% and 55.6%, respectively (limited disease, 9.5% and 66.75%; extensive disease, 0% and 40%, respectively). The median progression free survival was 31.9 weeks (limited disease, 36.1 weeks; extensive disease, 28.9 weeks; 95% confidence interval, 25.6-36.0 weeks), and the median overall survival was 52.4 weeks (limited disease, 54.9 weeks; extensive disease, 30.1 weeks; 95% confidence interval, 39.6-57.7 weeks). CONCLUSIONS: Combination therapy with topoisomerase I and II inhibitors is a safe and effective regimen for patients with SCLC. Future research on this combination should focus on an oral regimen for patients with extensive disease and poor tolerance to cisplatin. The authors recommend an oral dosage of topotecan at 1.2 mg/m(2) per day (equivalent to intravenous topotecan at 0.75 mg/m(2) per day) for 5 days followed by etoposide 50 mg twice daily for 7 days.

Administration, Oral↗
PubMed2002

Tumor p16M is a possible marker of advanced stage in non-small cell lung cancer.

BACKGROUND AND OBJECTIVES: The inactivation of the tumor suppressor gene p16 by methylation (p16M) has been recognized recently as an important process in the oncogenesis for a variety of carcinomas. There have been few reports of its use in lung cancer. We investigate p16M in patients with non-small cell lung cancer (NSCLC). METHODS: p16M in tumor, plasma, and pleural lavage fluid from patients with resectable NSCLC were investigated by using methylation-specific polymerase chain reaction. RESULTS: Of the 33 patients studied, 14 (42%) had p16M tumors. There was a significant association between p16M tumors and advanced TNM staging (stage III or IV, P=0.047, Fisher exact test). Circulating p16M was identified in 2 of the 14 patients with p16M tumor and was also associated with advanced TNM staging (P=0.049). The presence of plasma p16M in NSCLC patients and in p16M tumor patients was associated with poor survival and shorter disease-free survival (P=0.0028, P=0.0039, Kaplan-Meier log rank). In addition, p16M was present in three preresectional and four postresectional lavage samples. Preresectional p16M was associated with poor survival and shorter disease-free survival (P=0.0085). p16M tumor involving the visceral pleura was significantly associated with positive p16M postresectional lavage. CONCLUSIONS: Positive tumor and plasma p16M indicate advanced staging in NSCLC. Patients with plasma and preresection pleural lavage p16M have shorter survival. Further research in this direction is warranted.

Adult↗