Calvin Sh Ng

Impact of Video-Assisted Thoracoscopic Major Lung Resection on Immune Function

Video-assisted thoracoscopic major lung resection for early stage non-small-cell lung carcinoma has been associated with less postoperative pain, better preserved pulmonary function, shorter hospital stay, and enhanced tolerance of adjuvant chemotherapy compared to thoracotomy. Initial concerns regarding safety, oncological clearance, and cost effectiveness were unfounded. Several recent trials have reported improved long-term survival in patients with early stage non-small-cell lung carcinoma undergoing video-assisted thoracoscopic major lung resection, compared to the open technique, although there are inconsistencies. Interestingly, the immune status and autologous tumor killing ability of lung cancer patients have previously been associated with long-term survival. Video-assisted thoracoscopic lung resection results in an attenuated postoperative inflammatory response, but more importantly, it better preserves postoperative immune function. Circulating natural killer and T-cell numbers, T-cell oxidative activity, and levels of immunochemokines such as insulin growth factor binding protein-3 are higher after video-assisted thoracoscopic surgery than after thoracotomy. Recently, interest has developed in the role of the angiogenesis factor, vascular endothelial growth factor, after cancer surgery. Whether differences in immunological and biochemical mediators contribute towards improved long-term survival following video-assisted thoracoscopic major lung resection for cancer remains to be confirmed.

Mitral valve repair: past, present, and future.

Mitral valve repair is the operation of choice for mitral valve regurgitation, with appropriate selection. Studies have shown that mitral repair is associated with a decrease in both long-term thromboembolic complications and mortality. Since its initial description, various selection criteria and techniques of mitral valve repair have been discussed in the literature. This review serves as a synopsis of the previous achievements, present status, and possible future directions of mitral valve repair, specifically from an Asian perspective. Vast experience has been amassed in understanding mitral valve pathophysiology, and excellent surgical treatments for mitral regurgitation have been developed. With the efforts of pioneers in the field of mitral valve repair, standard surgical treatment strategies have been proven to restore the life-expectancy of patients with degenerative mitral regurgitation to that of the age-adjusted population. Minimally invasive techniques of mitral valve repair further reduce access trauma, and could potentially benefit patients previously excluded from conventional surgery.

Limiting inflammatory response to cardiopulmonary bypass: pharmaceutical strategies

A significant inflammatory response and subsequent organ dysfunction is known to be associated with the use of CPB. Pharmaceutical interventions, such as corticosteroids, statins and ACE-Is can attenuate the post-CPB inflammatory and immune response, by so doing, either directly or indirectly, reduce incidence of postoperative complications. Apart from its effects on lipids, statins have been found to reduce postoperative oxidative stress that may partly contribute towards improved graft patency. In addition, certain ACE-inhibitors can promote a pro-fibrinolytic environment, whose role on maintaining graft patency and clinical outcomes warrant further investigation. There is increasing evidence to support the use of combined clopidogrel with aspirin following CABG to improve graft patency, although its impact on reducing postoperative adverse events remains unclear. Factors such as drug bioavailability and individual variability in drug responses and metabolism of these antiplatelet agents can significantly influence clinical outcomes.

Minimizing single-port access in video-assisted wedge resection, with a hookwire

Single-port video-assisted thoracic surgery lung resection is increasing in popularity. In selected cases, the incision length of single-port video-assisted thoracic lung wedge resection can be minimized by preoperative strategic positioning of a percutaneous hookwire to allow intraoperative traction of the lung nodule to facilitate endostapler wedge resection, thereby substituting the sponge-holding forceps for lung retraction during the procedure.

Recurrent hemoptysis with Penicillium marneffei and Stenotrophomonas maltophilia in Job's syndrome

Pulmonary infection caused by the opportunistic organisms Penicillium marneffei and Stenotrophomonas maltophilia in patients with Jobs syndrome is rare and not well documented. The case of a 30-year-old man with Jobs syndrome who developed recurrent pneumonia and lung abscesses caused by P. marneffei and S. maltophilia, complicated by massive hemoptysis, is described. Bronchial artery embolization was successful in controlling the hemoptysis; however, the infection proved fatal despite appropriate antimicrobial therapy. A brief review of the literature on Jobs syndrome and its associated infective pulmonary manifestations is also presented.

Is hyperamylasemia after cardiac surgery due to cardiopulmonary bypass

Although hyperamylasemia has been reported in a large proportion of patients undergoing cardiac surgery with cardiopulmonary bypass, its clinical significance and pathogenetic mechanisms remain poorly understood. The study was designed to investigate whether avoidance of cardiopulmonary bypass would limit amylase elevation. Serum levels of amylase and lipase were measured preoperatively as well as 24 and 48 hours postoperatively in 58 patients undergoing elective coronary artery bypass grafting. Three surgical approaches were used: cardiopulmonary bypass (n = 32) and off-pump through a median sternotomy (n = 14) or a left minithoracotomy (n = 12). There was no hospital mortality or postoperative abdominal complications. Transient hyperamylasemia occurred in 14 patients: 7 (22%), 5 (36%), and 2 (17%) in the respective groups. The increase in amylase levels was similar among the groups. However, no lipase elevation was detected in any patient. There was no clear correlation between hyperamylasemia and increased creatinine levels. Perioperative plasma calcium levels were normal in patients who had hyperamylasemia. Our results indicate that hyperamylasemia after bypass surgery is not related to the use of cardiopulmonary bypass or the mode of surgical access.

Mediastinal follicular dendritic cell sarcoma with paraneoplastic pemphigus

Follicular dendritic cell sarcoma is a rare neoplasm of immune accessory cells. It occurs primarily in lymph nodes. Occurrences in the mediastinum are rarely reported. Diagnosis and management of follicular dendritic cell sarcoma remain unclear, and it is an under-recognized clinical entity. Only a few cases of paraneoplastic pemphigus as the first presentation of follicular dendritic cell sarcoma have been reported. We report an unusual case of follicular dendritic cell sarcoma of the anterior mediastinum, presenting as paraneoplastic pemphigus in a 62-year-old man. Typical histological features confirmed the diagnosis of follicular dendritic cell sarcoma, and surgical resection was successfully performed.

Cardiac Operation with Associated Pulmonary Resection: A Word of Caution

Pulmonary tuberculosis reactivation is an unusual cause of respiratory failure after cardiac surgery. Fulminating tuberculosis was reactivated in a 50-year-old man after combined coronary artery bypass grafting and pulmonary resection on cardiopulmonary bypass. Clinicians should be aware of the immunosuppressive effects associated with cardiopulmonary bypass, and the consequent potential for tuberculosis reactivation.

Giant Mediastinal Lipoblastoma

A 3-year-old girl with fever, increasing cough, and nasal discharge for 2 weeks, was found to have a giant mediastinal lipoblastoma. The tumor weighing 556 g was successfully resected.

Alveolar rhabdomyosarcoma of the anterior mediastinum with vessel invasion in a 4-month-old boy: a case report

IntroductionAlveolar rhabdomyosarcomas of the mediastinum in children are rarely reported. Multimodality therapy including chemotherapy, surgery and radiotherapy make up the backbone of the treatment of childhood rhabdomyosarcomas. Complete resection whenever achievable is an important prognostic factor. However, complete resection of tumors in the mediastinum often poses a unique challenge to thoracic surgeons due to their close proximity to important neurovascular structures. Complete resection may not always be possible and judicious peri-operative planning and preparation are required to avoid creating unnecessary surgical morbidities resulting in delay of adjuvant therapy.Case presentationA 4-month-old Chinese baby boy was presented to our hospital with stridor, shortness of breath and episodes of cyanosis. Imaging studies found an anterior mediastinal mass compressing the trachea and other neurovascular structures and he was diagnosed to have alveolar rhabdomyosarcoma. Our patient received upfront chemotherapy and subsequently open resection of the mass was attempted via median sternotomy. Intraoperatively, the mass had invaded into the great vessels, precluding a complete resection. Debulking surgery was performed instead and our patient received timely postoperative chemoradiotherapy.ConclusionsWe report a rare case of childhood alveolar rhabdomyosarcoma of the mediastinum with vascular invasion treated with chemoradiotherapy and debulking surgery. Complete resection was not possible due to the close proximity to the great vessels. Different surgical approaches to the mediastinum have been reported in adults and children alike. Regardless of the surgical access, the treatment of childhood rhabdomyosarcomas should be individualized, with careful balance between surgical clearance and surgical morbidity.