Sumin Shin

Enucleation of Esophageal Submucosal Tumors: A Single Institution's Experience

BACKGROUND Esophageal submucosal tumors (SMTs) are usually benign, and surgical enucleation is widely accepted as the treatment of choice. The goals of this study were to investigate the surgical outcomes after enucleation of esophageal SMTs and to establish the feasibility of video-assisted thoracoscopic enucleation. METHODS We performed a retrospective review of 87 patients who underwent enucleation of esophageal SMTs between 1995 and 2011 at Samsung Medical Center. RESULTS There were 59 men and 28 women in the study group, with a mean age of 43.3 years (range, 20-73 years). Fifty-eight (67%) patients were asymptomatic. Among the remaining patients, the most common symptom was dysphagia (n=12). Transthoracic approaches were used in 79 patients, including 63 patients who underwent video-assisted thoracoscopic enucleation. Transabdominal approaches were performed in 8 patients. Pathologic diagnosis included leiomyoma (n=78 [89.7%]), gastrointestinal stromal tumors (GISTs) (n=5 [5.7%]), schwannoma (n=3 [3.4%]), and hemangioma (n=1 [1.1%]). The thoracoscopic enucleation group had a significantly shorter median hospital stay compared with the thoracotomy groups (5 versus 6 days; p=0.013). Overall, there were 2 postoperative leaks, including in 1 patient who underwent reoperation after enucleation. With the exception of 2 patients, there was no other major complications. One patient underwent esophagectomy for tumor recurrence after enucleation of GISTs. CONCLUSIONS Overall, surgical outcomes were excellent after enucleation. The thoracoscopic approach was feasible for most patients and was correlated with a shorter hospital stay. However, careful management is warranted after enucleation of GISTs considering the recurrence risk.

A Prospective Phase II Trial of Induction Chemotherapy with Docetaxel/Cisplatin for Masaoka Stage III/IV thymic Epithelial Tumors

Background: Initial complete resection is a powerful prognostic indicator of survival in thymic epithelial tumors (TETs), but is obviously related to tumor stage. Here, we report the results of a prospective study of neoadjuvant docetaxel/cisplatin in locally advanced TETs. Methods: Patients with histologically proven, Masaoka stage III/IV TETs at presentation were enrolled in this open-label, phase II, nonrandomized study. Patients received docetaxel 75 mg/m2 I.V, followed by cisplatin 75 mg/m2 I.V on day 1 of every 3-week cycle. After three cycles, surgical resection was performed if the tumor was considered resectable. Results: From March 2007 to July 2011, 27 patients were enrolled in the trial. Masaoka stage at presentation was III (n = 8; 29.6%), IVA (n = 17; 63.0%), and IVB (n = 2; 7.4%). Histologic types were nine thymomas (33.3%) and 18 thymic carcinomas (66.7%). After completion of neoadjuvant chemotherapy, 17 patients (63.0%) achieved partial response and 10 (37.0%) had stable disease. Nineteen patients (70.4%) underwent surgery and eight did not because of surgeons’ decision (n = 5), patient refusal (n = 2), or decision to undergo radiation therapy instead (n = 1). Fifteen among the 19 patients achieved complete resection (78.9%), which yields 55.6% of complete resection rate with intent-to-treat analysis. The most common side effects of severity greater than grade 3 were neutropenia and diarrhea. With a median follow-up of 42.6 months, 4-year overall survival, and progression-free survival in all patients was 79.4 and 40.6%, respectively. Conclusion: Neoadjuvant docetaxel/cisplatin is both feasible and well tolerated, and potentially improves surgical resectability in patients with advanced TETs.

Surgical Treatment of Anastomotic Recurrence after Gastrectomy for Gastric Cancer

Background The purpose of this study was to evaluate the outcome of reoperation with curative intent for the treatment of anastomotic recurrent gastric cancer. Methods Ten patients with anastomotic recurrence of gastric cancer who underwent reoperation from November 1995 to February 2011 were analyzed retrospectively. The time interval between the first operation and reoperation, recurrence pattern, type of surgery, survival, and postoperative outcome were analyzed. Results The average time to recurrence after initial surgery was 48.8 months (median, 23.5 months). Of the ten patients, eight (80.0%) had recurrence at the esophagojejunostomy, one (10.0 %) at the esophagogastrostomy, and two (20.0%) at the esophagus. Among these patients, five had combined metastasis or invasion to major organs in addition to anastomotic recurrence. Complete resection was achieved in five patients (50.0%), and incomplete resection or bypass surgery was performed in the remaining five patients (50.0%). The overall median survival time was 7.0 months (range, 2.2 to 105.5 months). The median survival time following complete resection and palliative surgery (incomplete resection or bypass surgery) was 28.1 months (range, 4.2 to 105.5 months) and 5.5 months (range, 2.2 to 7.5 months), respectively. Conclusion Surgical resection of anastomotic recurrent gastric cancer should be implemented only in selected patients in whom complete resection is possible.

Genotyping of Mycobacterium intracellulare isolates and clinical characteristics of lung disease.

BACKGROUND Variable number of tandem repeats (VNTR) loci were recently identified in Japanese isolates of Mycobacterium intracellulare. We hypothesised that some mycobacterial genotypes are more virulent than others, resulting in particular genotypes being associated with disease phenotype and progression. OBJECTIVE To evaluate the VNTR loci of M. intracellulare in clinical isolates from Korean patients, and investigate the association between mycobacterial genotype and disease phenotype and progression. DESIGN In total, 70 M. intracellulare clinical isolates were genotyped using 16 M. intracellulare VNTR loci. RESULTS VNTR typing showed strong discriminatory power and genetic diversity for molecular epidemiological studies of M. intracellulare. In a phylogenetic tree, the M. intracellulare clinical isolates were divided into two clusters (A and B). Cluster A was observed more frequently (77%) than Cluster B; however, there was no association between the clinical characteristics, disease progression, drug susceptibility and clusters based on VNTR genotyping. CONCLUSIONS VNTR typing could be used for epidemiological studies of M. intracellulare lung disease; however, no association was found between the specific VNTR genotypes of M. intracellulare and the clinical characteristics of Korean patients.

Clinical significance of mycobacterial genotyping in Mycobacterium avium lung disease in Korea.

SETTING A recent study in Japan found that mycobacterial genotyping was associated with disease progression and susceptibility to certain drugs in Mycobacterium avium lung disease. However, it is not known whether this association is true in other populations. OBJECTIVE To investigate the association between mycobacterial genotype, clinical characteristics and the progression of M. avium lung disease in Korean patients. DESIGN A total of 102 M. avium clinical isolates were genotyped using M. avium tandem repeats-variable number of tandem repeats (MATR-VNTR). RESULTS MATR-VNTR typing demonstrated a high discriminatory power and genetic diversity for molecular epidemiological studies of M. avium. In the phylogenetic tree, the M. avium clinical isolates were divided into three major clusters: A, B and C. Cluster A was observed most frequently (64/102, 63%), whereas cluster C was found in a minor proportion of the isolates (8/102, 8%). However, there was no association between the clinical characteristics, disease progression and drug susceptibility and the phylogenetic tree based on VNTR genotyping. CONCLUSIONS MATR-VNTR genotyping may be useful for epidemiological studies of M. avium lung disease; however, no association was found between the specific VNTR genotypes of M. avium and the clinical characteristics of Korean patients.

Prognosis of unexpected and expected pathologic N1 non-small cell lung cancer.

BACKGROUND This study was undertaken to compare clinicopathologic features and survival between patients with unexpected N1 (clinical N0-pathologic N1) and expected N1 disease (clinical N1-pathologic N1) after operation for non-small cell lung cancer. METHODS From 2003 to 2009, 305 patients who were found to have pathologic N1 disease after complete resection were retrospectively analyzed. Among these, 177 patients had negative findings for both computed tomography (CT) and positron emission tomography (PET)/CT (group cN0). Sixty-eight patients had negative CT and positive PET/CT or positive CT and negative PET/CT findings (group cN0-1). Sixty patients had positive findings for both CT and PET/CT (group cN1). RESULTS Patients in the cN1 group had larger tumors (p<0.001), greater pathologic T stage (p=0.018), and greater percentage of squamous cell carcinoma (p<0.001) than did those in the other groups. Patients in the cN1 group had a greater number of positive N1 lymph nodes (p=0.004) and more frequent extracapsular nodal invasion (p<0.001). The 5-year overall survival was 66%, 63%, and 58% in groups cN0, cN0-1, and cN1, respectively (cN0 vs cN0-1, p=0.958; cN0 vs cN1, p=0.038). The 5-year disease-free survival was 54%, 52%, and 39% in groups cN0, cN0-1, and cN1, respectively (cN0 vs cN0-1, p=0.862; cN0 vs cN1, p=0.01). CONCLUSIONS Patients with unexpected N1 disease showed better survival than did those with expected N1 disease, which seemed to be related to the pathologically minimal extent of the primary tumor and nodal involvement.

Carinal resection and reconstruction in thoracic malignancies

The purpose of this study was to present clinical outcomes of malignant tumors involving the carina after surgery in order to establish the management guidelines.

Clinical stage T1–T2N0M0 oesophageal cancer: accuracy of clinical staging and predictive factors for lymph node metastasis

OBJECTIVES The aim of this study was to evaluate the accuracy of clinical staging in patients with clinical stage T1-2N0M0 (cT1-T2N0M0) oesophageal cancer and to assess predictive factors associated with lymph node (LN) metastases in those patients. METHODS From 2005 through 2010, 240 patients were identified with cT1-T2N0M0 oesophageal cancer followed by oesophageal resection without induction therapy. Clinical staging was performed by both endoscopic ultrasound (EUS) and positron-emission tomography (PET) scans. RESULTS The study included 174 patients with cT1N0M0 and 66 patients with cT2N0M0 stage oesophageal cancer. Clinical T stage correlated with pathological T stage in 182 of 240 (76%) patients: 167 of 174 patients (96%) for cT1N0 and 15 of 66 patients (23%) for cT2N0. Nodal metastases occurred in 53 patients (22%) and the prevalence of nodal disease was 16% in cT1N0 patients and 39% in cT2N0 patients. Clinical tumour, nodal, metastasis (TNM) staging accurately predicted pathological TNM staging in 62% of patients (148 of 240), with an accuracy of 79% for cT1N0 and 15% for cT2N0. Among the 62 clinically understaged patients, 53 were pathologically upstaged because of nodal metastases. Significant factors associated with LN metastases on multivariate logistic regression were cT2 stage (odd ratios (ORs): 2.87, 95% confidence intervals (CIs): 1.44-5.69, P = 0.003), poor differentiation (well/unknown vs poor, OR: 5.51, CI: 1.38-22.00, P = 0.01) and maximum standardized uptake value (SUVmax) >3.15 (OR: 1.99, 95% CI: 1.01-3.96, P = 0.047). CONCLUSIONS Clinical staging using both EUS and PET demonstrated high accuracy for predicting cT1N0M0 oesophageal cancer pathological staging, but was inadequate for predicting staging for cT2N0M0 cancer. Clinical factors such as SUVmax and tumour differentiation could help select patients with cT1-T2N0M0 tumours that might be upstaged because of unexpected LN metastases.

Surgical Treatment for Non-Small Cell Lung Cancer in Patients on Hemodialysis due to Chronic Kidney Disease: Clinical Outcome and Intermediate-Term Results.

Background Patients on dialysis undergoing surgery belong to a high-risk group. Only a few studies have evaluated the outcome of major thoracic surgical procedures in dialysis patients. We evaluated the outcomes of pulmonary resection for non-small cell lung cancer (NSCLC) in patients on hemodialysis (HD). Methods Between 2008 and 2013, seven patients on HD underwent pulmonary resection for NSCLC at our institution. We retrospectively reviewed their surgical outcomes and prognoses. Results The median duration of HD before surgery was 55.0 months. Five patients underwent lobectomy and two patients underwent wedge resection. Postoperative morbidity occurred in three patients, including pulmonary edema combined with pneumonia, cerebral infarction, and delirium. There were no instances of in-hospital mortality, although one patient died of intracranial bleeding 15 days after discharge. During follow-up, three patients (one patient with pathologic stage IIB NSCLC and two patients with pathologic stage IIIA NSCLC) experienced recurrence and died as a result of the progression of the cancer, while the remaining three patients (with pathologic stage I NSCLC) are alive with no evidence of disease. Conclusion Surgery for NSCLC in HD patients can be performed with acceptable perioperative morbidity. Good medium-term survival in patients with pathologic stage I NSCLC can also be expected. Pulmonary resection seems to be the proper treatment option for dialysis patients with stage I NSCLC.

Once-daily dosing of amikacin for treatment of Mycobacterium abscessus lung disease

SETTING Tertiary referral centre, Samsung Medical Center, South Korea. OBJECTIVE To evaluate the pharmacokinetic parameters and toxicities of once-daily amikacin (AMK) dosing for lung disease due to Mycobacterium abscessus. DESIGN A retrospective review of 48 patients with M. abscessus lung disease who received once-daily AMK for 4 weeks between January 2012 and June 2015. RESULTS With a starting dose of 15 mg/kg/day and adjustment of AMK dose according to the peak serum level (Cmax), the Cmax target of 55-65 μg/ml was achieved in 31.3% (15/48) of patients in the first week, 68.8% (33/48) in week 2, 91.7% (44/48) in week 3 and 95.8% (46/48) in week 4. Transient nephrotoxicity developed in 6.3% (3/48) of patients and ototoxicity in 25.0% (6/24), which was determined by audiogram as hearing loss, asymptomatic in five patients and tinnitus in one. Multivariate analysis revealed that the highest drug concentration 12 h after administration was significantly associated with the development of toxicities (adjusted odds ratio 1.862, P = 0.047). CONCLUSION Our results suggest that once-daily AMK for 4 weeks with a target Cmax of 55-65 μg/ml can be used in patients with M. abscessus lung disease, with careful monitoring of toxicity.