Limited Resection Group Research Articles

Sublobar resection for lung adenocarcinoma less than 2 cm containing solid or micropapillary components radiologically presented as consolidation-to-tumor ratio (CTR) ≤0.25 [ground-glass opacity (GGO)

The suitability of sublobar resection as a surgical approach for early-stage non-small cell lung cancer (NSCLC) remains unclear. This study investigated the feasibility of sublobar resection in patients with pathological-stage IA adenocarcinoma less than 2 cm characterized by a high-risk pathological subtype but exhibiting radiologically noninvasive features. We conducted a retrospective review of patients diagnosed with pathological stage IA lung adenocarcinoma who underwent surgical intervention between 2013 and 2017. The inclusion criteria included a maximum tumor diameter of 2.0 cm or less, a consolidation-to-tumor ratio (CTR) of 0.25 or less, and a histopathological confirmation of a solid or micropapillary component. Patients were categorized into sublobar resection and lobectomy groups, and propensity score matching was employed to mitigate potential confounders. The primary endpoints were lung cancer-specific survival (LCSS) and overall survival (OS). The study comprised 149 patients, with 84 in the lobectomy group and 65 in the limited resection group. In the overall cohort, the 5-year LCSS was 100% for both groups, while the 5-year OS was 97.6% (95% CI: 94.41-100.00%) in the lobectomy group and 100% in the sublobar resection group (P=0.21). After propensity score matching, the LCSS remained at 100% for both groups, and the 5-year OS was 97.14% in the lobectomy group and 100% in the sublobar resection group (P=0.32). Based on our experience, for lung adenocarcinoma containing solid/micropapillary subtype, a size less than 2 cm, and a CTR ≤0.25, the oncological outcomes appeared to be comparable between sublobar resection and lobectomy, suggesting that sublobar resection might serve as an equivalent alternative to lobectomy for such lesions.

Long-term follow-up of non-myasthenic patients with early-stage thymoma who underwent extended thymectomy or limited resection

BackgroudThe standard resection for early-stage thymoma is total thymectomy and complete tumour excision with or without myasthenia gravis but the optimal surgery mode for patients with early-stage non-myasthenic thymoma is debatable. This study analysed the oncological outcomes for non-myasthenic patients with early-stage thymoma treated by thymectomy or limited resection in the long term. MethodsPatients who had resections of thymic neoplasms at Taipei Veteran General Hospital, Taiwan between December 1997 and March 2013 were recruited, exclusive of those combined clinical evidence of myasthenia gravis were reviewed. A total of 113 patients were retrospectively reviewed with pathologic early stage (Masaoka stage I and II) thymoma who underwent limited resection or extended thymectomy to compare their long-term oncologic and surgical outcomes. ResultsThe median observation time was 134.1 months [interquartile range (IQR) 90.7–176.1 months]. In our cohort, 52 patients underwent extended thymectomy and 61 patients underwent limited resection. Shorter duration of surgery (p < 0.001) and length of stay (p = 0.006) were demonstrated in limited resection group. Six patients experienced thymoma recurrence, two of which had combined myasthenia gravis development after recurrence. There was no significant difference (p = 0.851) in freedom-from-recurrence, with similar 10-year freedom-from-recurrence rates between the limited resection group (96.2 %) and the thymectomy group (93.2 %). Tumour-related survival was also not significantly different between groups (p = 0.726).result ConclusionPatients with early-stage non-myasthenic thymoma who underwent limited resection without complete excision of the thymus achieved similar oncologic outcomes during the long-term follow-up and better peri-operative results compared to those who underwent thymectomy.

Sublobectomy for stage IA1-2 invasive lung adenocarcinoma with consolidation tumor ratio ≤ 0.25.

Sublobectomy for early-stage non-small cell lung cancer (NSCLC) remains a matter of debate. This study aimed to discuss the feasibility of sublobectomy in patients with pathological-stage IA1-2 confirmed as pathologically invasive but radiologically noninvasive adenocarcinoma. From 2011 to 2019, we screened clinical stage IA1-IA2 lung cancer patients who underwent surgery at the Guangdong Provincial People's Hospital (GDPH). Inclusion criteria were maximum tumor diameter of 2.0cm or less, consolidation tumor ratio (CTR) ≤ 0.25, and pathologically confirmed invasive adenocarcinoma. Sublobectomy (segmentectomy and wedge resection) and lobectomy groups were created, and propensity scores were computed. The primary endpoints were lung cancer-specific overall survival (LCSS) and LCS- relapse-free survival (LCS-RFS) after adjusting propensity scores. A total of 1731 patients were screened, and 100 patients were enrolled. The lobectomy group had 51 patients and the limited resection group had 49. No cases relapsed, and two patients died from nontumor causes. For the entire cohort, the 5-year LCSS and 5-year LCS-RFS were 100% in the lobectomy and limited resection groups. When propensity scores matched, there were no differences in LCSS and LCS-RFS between the two groups (LCSS:100%, LCS-RFS 100% in lobectomy and limited resection, respectively). Sublobectomy may be curative for pathologically invasive but radiologically noninvasive adenocarcinoma at pathological stage IA1-2.

Impact of Surgical Modalities on Long-term Survival Outcomes of Patients with Duodenal Gastrointestinal Stromal Tumor.

The optimal surgical modality for duodenal gastrointestinal stromal tumor (GIST) remains undefined. The purpose of this study was to evaluate long-term survival outcomes of patients who underwent radical resection (RR) or limited resection (LR) of duodenal GIST. A total of 325 patients identified from the Surveillance, Epidemiology and End Results (SEER) database who underwent surgery for duodenal GIST between 1986 and 2016 were classified into a LR group and a RR group based on the type of surgery received. Propensity score matching (PSM) was performed to minimize the selection bias in comparisons. Disease-specific survival (DSS) and overall survival (OS) were observed, and factors affecting the survival outcome were analyzed. In the entire cohort, 105 patients (32.3%) underwent RR and 220 (67.7%) received LR. Both the 5-year OS and DSS in RR group were significantly better than those in LR group (71.0% vs. 54.1%, P = 0.014; 66.6% vs. 49.1%, P = 0.025). PSM resulted in 95 pairs of patients, with long-term outcomes being comparable between the two groups. After adjusting covariates in the propensity matched cohort, the type of surgery still showed no significant impact on OS (hazard ratio [HR] 1.160; 95% confidence interval [CI] 0.662-2.033) and DSS (HR 1.208; 95% CI 0.686-2.128). Surgical modalities do not seem to have a significant impact on long-term survival outcomes of patients with duodenal GIST and should mainly depend on the tumor size and location.

Limited resection vs. pancreaticoduodenectomy for primary duodenal adenocarcinoma: a systematic review and meta-analysis.

It is well known that surgery is the mainstay treatment for duodenal adenocarcinoma. However, the optimal extent of surgery is still under debate. We aimed to systematically review and perform a meta-analysis of limited resection (LR) and pancreatoduodenectomy for patients with duodenal adenocarcinoma. A systematic electronic database search of the literature was performed using PubMed and the Cochrane Library. All studies comparing LR and pancreatoduodenectomy for patients with duodenal adenocarcinoma were selected. Long-term overall survival was considered as the primary outcome, and perioperative morbidity and mortality as the secondary outcomes. Fifteen studies with a total of 3166 patients were analyzed; 995 and 1498 patients were treated with limited resection and pancreatoduodenectomy, respectively. Eight and 7 studies scored a low and intermediate risk of publication bias, respectively. The LR group had a more favorable result than the pancreatoduodenectomy group in overall morbidity (odd ratio [OR]: 0.33, 95% confidence interval [CI] 0.17-0.65) and postoperative pancreatic fistula (OR: 0.13, 95% CI 0.04-0.43). Mortality (OR: 0.96, 95% CI 0.70-1.33) and overall survival (OR: 0.61, 95% CI 0.33-1.13) were not significantly different between the two groups, although comparison of the two groups stratified by prognostic factors, such as T categories, was not possible due to a lack of detailed data. LR showed long-term outcomes equivalent to those of pancreatoduodenectomy, while the perioperative morbidity rates were lower. LR could be an option for selected duodenal adenocarcinoma patients with appropriate location or depth of invasion, although further studies are required.

Outcomes of limited resection for patients with intraductal papillary mucinous neoplasm of the pancreas: A single-center experience

Background/ObjectivesThe aim of this study was to clarify the oncological outcomes of patients with intraductal papillary mucinous neoplasm (IPMN) who underwent limited resection (LR). MethodsThis retrospective study analyzed the data of 110 patients with IPMN. Patients with IPMN without a history of pancreatitis who had neither tumor infiltration nor regional lymph node swelling on imaging findings underwent LR. We assessed the oncological outcomes of LR for patients with IPMN by comparing the surgical outcomes of LR and standard resection. ResultsLR was performed in 50 patients (45.5%), including duodenum-preserving pancreatic head resection (n = 31), middle-pancreatectomy (n = 12), spleen-preserving distal pancreatectomy (n = 3), total parenchymal pancreatectomy (n = 3), and partial resection (n = 1). In the LR group, 18 patients had postoperative complications of Clavien-Dindo classification ≥ IIIa. After histopathological examination, the presence of high-grade dysplasia (HGD) and invasive carcinoma (IC) were observed in nine and three patients, respectively, in the LR group, and eight and 22 patients, respectively, in the standard resection group. There was a significant difference in the histopathological diagnosis of IC between the two groups (p < 0.001). Finally, in the LR group, postoperative recurrences occurred in three patients, and the 5-, 10-, and 15-year disease-specific survival rates were all 97.0%. ConclusionsFor patients with IPMN judged to have no infiltrating lesions based on the detailed imaging examination, LR is acceptable and may be considered as an alternative to standard resection.

Impacts of thoracoscopic surgery and high grade histologic subtypes on spread through air spaces in small stage I lung adenocarcinomas.

Spread through air spaces (STAS) as a pattern of invasion in lung adenocarcinomas had been recognized by WHO in 2015. Moreover, STAS was associated significantly with aggressive micropapillary or solid components when presented predominant pattern in lung adenocarcinomas, which had a poor prognostic significance. Small amounts of micropapillary or solid with components could also reduce overall survival and recurrence-free survival but its impact on STAS is unknown now. Some studies have demonstrated manipulations of surgeons and pathologists could affect STAS but the degree of these impacts is not clear. We reviewed resected small (≤ 2cm) stage I invasive lung adenocarcinomas by thoracoscopic surgery at our institution from January 2017 to October 2018 (n = 277). Micropapillary or solid pattern was considered to be present when the subtype occupied at least 1% of the entire tumor. Lobectomy and segmentectomy were performed using three portals thoracoscopic surgery. Statistical analysis was performed to analyze the correlations of STAS and clinicopathological characteristics. Moreover, we also analyzed the correlated factors of STAS in solid nodules. STAS was found in 59 of 163 (36.2%) lobectomy cases and 27 of 114 (23.7%) limited resection cases. Lobectomy group showed a higher incidence of STAS compared with limited resection group (p = 0.027), but the difference was disappeared in multivariate analysis, which showed that STAS was significantly correlated to solid nodules and presence of high grade histologic subtype (mircopapillary or solid). However, both lobectomy and presence of high grade histologic subtype were significantly correlated with STAS in solid nodules. The small amounts of high grade histologic subtypes were also associated with STAS. Thoracoscopic surgery could affect STAS to some degree.

P3.16-20 Feasibility of Limited Resection for Peripheral Small-Sized Non-Small Cell Lung Cancer According to FDG Accumulation and Imaging Findings

With the progress of diagnostic imaging modalities, such as CT and FDG-PET, the number of resectable lung cancer, particularly small peripheral lung cancer, is increasing. We focused on the SUVmax of FDG-PET as a prognostic factor for lung cancer and established criteria for limited resection on the basis of CT findings and SUVmax. Since 2007, we continuously monitored the recurrence and prognosis of non-small cell lung cancers (NSCLCs) resected using our criteria. Here, we report the results of this study. Between December 2007 and December 2015, 611 consecutive patients underwent surgery for NSCLC at our institution. Of these, 73patients with cT1aN0M0 who underwent limited resection (partial resection or segmentectomy) were enrolled. The criteria for undergoing limited resection were as follows: ①tumor GGO ratio of ≥0.75and ② tumor SUVmax of ≤1.5. GGO ratio was calculated using the following equation: GGO ratio=[(maximum diameter of the tumor) – (maximum diameter of tumor consolidation)] / (maximum diameter of the tumor). The group that met our criteria and underwent limited resection was designated as intended limited resection group (ILR group), and the group subjected to limited surgery without meeting the criteria treated as control group. The study included 35 men and 38 women with a median age of 65 (range, 36–84) years. In total, 51 patients who met our criteria were included in the ILR group, and 21 patients who did not meet the criteria were included in the control group. The control group was selected for limited resection in terms of complications, pulmonary hypofunction, and heart failure. Regarding surgical approach, in the ILR group, 19 patients underwent partial resection and 32 underwent segmentectomy; in the control group, 13 patients underwent partial resection and 8 underwent segmentectomy. According to our criteria, no relapsed cases were reported in the ILR group. Moreover, the 5-year overall survival rates of the ILR and control groups were 100% and 60.5%, respectively, and the disease-free survival rates were 100% and 56.0%, respectively, indicating a significant difference (P < 0.0001). In the control group, 6 patients showed the recurrence of lung cancer. In this study, we analyzed the feasibility of our criteria for performing limited resection on the basis of CT findings and SUVmax. In the ILR group, no relapsed cases were reported, suggesting that our criteria may be useful in determining patient’s eligibility for undergoing reduction surgery.

Laparoscopic liver resection of the segments 7 and 8

Introduction: Laparoscopic liver resection (LLR) of the Segments 7 and 8 (S78) is still difficult. The present study elucidates safety and appropriate approach of LLR for S78 tumors. Methods: Between June 2010 and December 2017, 170 patients underwent LLR at our hospital, and 57 (33.5%) hepatectomies were for S78 tumors. These were divided in 2 groups: those patients with subsegmentectomy or more (Group S, n=37) and partial or limited resection (Group P, n=20), and analyzed retrospectively. Results: Indicated diseases were HCC in 44, metastases in 11, cholangiocarcinoma in 1 and benign tumor in 1. Median age (Group S, 69 years vs. Group P 68.5 years), male: female ratio (25:12 vs. 12:8), BMI (22.9 vs.24.2 kg/m2), history of abdominal surgery (48.6% vs.55.0%), tumor size (2cm vs. 1.5cm, p=0.092), number of tumors (1 vs. 1), and ICG R15 rate (12.5% vs. 17.5%, p=0.081) were not different. Surgical duration (217 min vs. 178 min, p=0.192), blood loss (215 g vs. 300g, p=0.632), number of ports (6 vs. 6), wound length (5cm vs. 5cm), morbidity (>Clavien-Dindo classification,Grade 2) (8.1% vs. 25%, p=0.081), and hospital stay (13 days vs. 12.5 days) were not different. However, open conversion rate (2.7% vs. 15%, p=0.031) and positive surgical margin (0% vs. 20%, p=0.026) were significantly different. Conclusion: LLR for S78 tumors is feasible with acceptable morbidity and mortality rates. Anatomical subsegmentectomy or more extensive liver resection is preferable when liver function reserve is in a tolerable range.

Clinicopathologic Characteristics and Optimal Surgical Treatment of Duodenal Gastrointestinal Stromal Tumor

BackgroundThe clinicopathologic characteristics of duodenal gastrointestinal stromal tumor (GIST) were unclear and the optimal surgical procedure for duodenal GIST remains poorly defined. We aimed to analyze clinicopathological characteristics, survival outcomes based on the surgical procedure, and recommend optimal surgical treatment for duodenal GIST. MethodsFrom July 2000 to April 2017, 118 patients with localized duodenal GIST underwent curative surgical resection at a single institution. We retrospectively reviewed the clinicopathological characteristics and survival outcomes. ResultsThe 5-year overall survival (OS) and disease-free survival (DFS) rates were 94.9 and 79.2%, respectively. On multivariate analysis, the mitotic count was a statistically significant prognostic factor for DFS. Limited resection (LR) was performed in 20 patients with GIST in the first or fourth portion of the duodenum. Both LR and pancreaticoduodenectomy (PD) were performed in 98 patients with GIST in second or third portion of the duodenum. The patients in the LR group had less late complications than in the PD group and no postoperative newly developed diabetes mellitus. The minimally invasive LR (MI-LR) group had a shorter duration of surgery and shorter length of postoperative hospital stay. ConclusionLR is a feasible and effective surgical treatment for patients with small-sized and antimesenteric-sided duodenal GIST in terms of late complications and postoperative diabetic complications. MI-LR has better perioperative outcomes than open LR. Therefore, we should consider MI-LR as an optimal surgical treatment for selected patients with duodenal GIST.

The clinicopathologic features and optimal surgical treatment of duodenal gastrointestinal tumor.

519 Background: Because of unclear clinicopathologic features, the optimal surgical procedure for duodenal gastrointestinal stromal tumor (GIST) remains poorly defined. We analyze clinicopathological features and recommend optimal surgical treatment of duodenal GIST. Methods: From July, 2000 to April 2017, 118 patients who had localized duodenal GIST were treated by curative surgical resection at a single institution. We retrospectively reviewed the clinicopathological characteristics and survival outcomes. Results: In survival analysis of all patients, 5-year overall survival (OS) and disease-free survival (DFS) rate were 94.9 and 79.2%, respectively. 19 patients developed recurrent disease at a median of 26.1 months from surgery and most common recurrence site was liver (63.2%). In multivariate analysis, mitotic count was the statistically significant prognostic factors of DFS. Our 20 cases of duodenal GIST in 1st or 4th portion were completely resected by limited resection(LR), regardless of tumor size. 98 patients with GISTs in 2nd or 3rd portion of duodenum underwent LR (n = 53) or pancreaticoduodenectomy (PD) (n = 45). Patients in the LR group had a smaller median tumor size (4.0 vs 5.3 cm, p = 0.026), more antimesenteric-sided location (41 vs 7cases, p &lt; 0.001), less late complications (1 vs 7 cases, p = 0.014) and no postoperative newly developed diabetes mellitus (0 vs 4 cases, p = 0.027) than those in the PD group. When 53 patients in LR group further divided into minimal invasive LR (MILR) (n = 12) and open-LR (n = 41), MILR group had shorter operation time (155.0 vs 218.8 minutes, p = 0.013) and postoperative hospital stay (12.0 vs 19.4 days, p = 0.036). Conclusions: Patients with duodenal GIST who underwent complete surgical resection have favorable survival outcomes. Predictor of disease recurrence at multivariate analysis was mitotic count. LR is feasible and effective surgical treatment for the patients with small-sized, and anti-mesenteric sided duodenal GIST in terms of long-term oncologic outcomes and quality of life. MILR has better perioperative outcomes than open LR. Therefore, we should consider MILR as optimal surgical treatment for the selected patients with duodenal GIST.

Clinicopathological and Prognostic Features of Surgical Management in Duodenal Gastrointestinal Stromal Tumors

Background and Objectives: The rarity of duodenal gastrointestinal stromal tumors (DGIST) led to only limited data being available on their management and prognosis. We retrospectively analyzed the clinicopathological features, surgical treatments, adjuvant therapy, and prognosis of DGIST. Methods: Sixty-one patients were identified at diagnosis of primary DGIST from February 2005 to December 2015. One hundred twenty six patients with small intestinal gastrointestinal stromal tutors (GIST) were selected as control groups. Survival analyses were calculated using the Kaplan-Meier method. Results: Three- and five-year recurrence/metastasis-free survival rates of patients with DGIST were similar to those of patients with small intestinal GIST (p > 0.05 for all). Out of 61 cases with DGIST, 45 patients were treated with Limited Resection (LR). Sixteen patients were treated with Pancreaticoduodenectomy (PD). The 3- and 5-year recurrence/metastasis-free survival rates of the PD group and LR group were of no significant difference (p > 0.05 for all). Univariate analysis indicated that factors including surgical approaches, mitotic count, size, and risk grades were significantly associated with recurrence/metastasis-free survival (log-rank test, p < 0.05). Multivariate analysis demonstrated that the mitotic count was independently correlated with a worse recurrence/metastasis-free survival. Conclusions: Patients with radical resected DGIST had a favourable prognosis, which is similar to that of small intestinal GIST. Both LR and PD were optimal choices for treating DGIST.

A Clinicopathological Study of Small Lung Adenocarcinoma 1 cm or Less in Size: Emphasis on Histological Subtypes Associated With Lymph Node Metastasis and Recurrence.

The aim of this study was to assess the prognostic significance of the newly proposed 2015 World Health Organization (WHO) lung adenocarcinoma classification for patients undergoing resection for small (≤1 cm) lung adenocarcinoma. We also investigated whether lobectomy offers prognostic advantage over limited resection for this category of tumors. A retrospective study of resected pulmonary adenocarcinomas (n = 83) in sizes 1 cm or less was carried out in which comprehensive histologic subtyping was assessed according to the 2015 WHO classification on all consecutive patients who underwent lobectomy or limited resection between 2008 and 2015. Correlation between clinicopathologic parameters and the difference in recurrence between lobectomy and limited resection group was evaluated. Our data show that the proposed 2015 WHO classification identifies histological subsets of small lung adenocarcinomas with significant differences in prognosis. No recurrence was noted for patients with adenocarcinoma in situ and minimally invasive adenocarcinoma. Invasive adenocarcinomas displayed high heterogeneity and the presence of micropapillary component of 5% or greater in adenocarcinomas was significantly related to lymph node involvement and recurrence ( P < .001). Stage Ia patients who underwent limited resection had a higher risk of recurrence than did those treated by lobectomy (P < .05). Application of the 2015 WHO classification identifies patients with adenocarcinoma in situ and minimally invasive adenocarcinoma had excellent prognosis. Micropapillary pattern was associated with high risk of lymph node metastasis and recurrence.

P3.01-002 The Clinical Impact of Spread through Air Spaces (STAS) in Surgically Resected pStage I Lung Squamous Cell Carcinoma: Topic: Morphology

Spread through air spaces (STAS) is identified as a newly invasive pattern in lung adenocarcinoma. It contributes to the significantly increased recurrence rate for patients with small adenocarcinoma. But the presence of STAS and its clinical impact has remained uncertain in squamous cell carcinoma (SQCC). The purpose of this study is to analyze whether STAS happens in surgically resected pathological Stage I (pStage I) lung SQCC. We retrospectively reviewed 141 pStage I patients of SQCC (Female/Male, 13/128; Smoker/Never smoker, 135/6; pStage IA/IB, 93/48). Tumor STAS was defined as tumor cells within the air spaces in the lung parenchyma beyond the edge of the main tumor. Statistical analyses were conducted to investigate the relationship between its presence and the clinicopathological background factors, including the clinical outcome. STAS was identified in 23 of 141 patients (16.3%) with limited (7.1%) and extensive (9.2%) feature, respectively. Both disease-free survival (DFS) and overall survival (OS) were significantly worse in the patients with STAS in comparison with the patients without STAS (5-year DFS, 35.1% vs. 65.6%, p<0.01; 5-year OS, 41.7% vs. 71.2%, p<0.01, respectively). In multivariate analyses adjusting for sex, year, smoking history and pStage, the presence of STAS was found to be an independent predictive factor of both DFS (HR=3.154, 95%CI: 1.592-6.249; p=0.001) and OS (HR=3.07, 95%CI: 1.595-5.911; p=0.0008). The 141 tumors were divided into patients who underwent limited resection and those who underwent standard resection in order to examine whether the surgical procedure affected the DFS and OS of patients with and without STAS. In the standard resection group, both 5-year DFS and 5-year OS were worse in the patients with STAS in comparison with the patients without STAS (44.1% vs. 68.3%, p=0.03; 53.8% vs. 72.3%, p=0.048, respectively). In the limited resection group, both 5-year DFS and 5-year OS were worse in the patients with STAS in comparison with the patients without STAS (0% vs.57.5%, p=0.001; 0% vs. 66.4%, p=0.001, respectively). STAS happened in lung SQCC and was found to be an independent predictive factor of both DFS and OS. Both 5-year DFS and 5-year OS were worse in the patients with STAS regardless of surgical procedure.

Lobectomy and limited resection in small-sized peripheral non-small cell lung cancer.

Although lobectomy is the standard surgical procedure for non-small cell lung cancer (NSCLC), recent studies show favorable outcomes after limited resection in patients with small-sized peripheral tumors. We conducted a randomized controlled trial of such patients to estimate postoperative outcomes and pulmonary function following these surgical techniques. Between 2005 and 2008, eligible patients with tumors of 2 cm or less were randomly assigned 1:1 to undergo lobectomy or limited resection; 32 and 33 NSCLC patients in each group, respectively, were analyzed. The primary end points were 5-year overall survival (OS) and disease-free survival (DFS), while the secondary end points were postoperative pulmonary function including forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV1). The 5-year OS rates were 93.8% and 90.9% in the lobectomy and limited resection groups, respectively (P=0.921). The 5-year DFS rates were 93.8% and 90.9% in the lobectomy and limited resection groups, respectively (P=0.714). These rates did not differ significantly between the two resection groups. The median postoperative/preoperative FVC ratios were 84.1% and 90.0% in the lobectomy and limited resection groups, respectively, while the median postoperative/preoperative FEV1 ratios were 81.9% and 89.1%, respectively. Both ratios were significantly higher in the limited resection group (P=0.032 and P=0.005 for FVC and FEV1 ratios, respectively). A similar outcome, with more preserved postoperative pulmonary function, was observed in patients who underwent limited resection compared to those who underwent lobectomy. Ongoing large-scale multi-institutional prospective randomized trials of lobar versus sublobar resection in patients with small peripheral NSCLCs will hopefully provide definitive information about intentional limited resection of small peripheral tumors.

Tumor Spread through Air Spaces is an Important Pattern of Invasion and Impacts the Frequency and Location of Recurrences after Limited Resection for Small Stage I Lung Adenocarcinomas

Tumor invasion in lung adenocarcinoma is defined as infiltration of stroma, blood vessels, or pleura. Based on observation of tumor spread through air spaces (STAS), we considered whether this could represent new patterns of invasion and investigated whether it correlated with locoregional versus distant recurrence according to limited resection versus lobectomy. We reviewed resected small (less than or equal to 2 cm) stage I lung adenocarcinomas (n = 411; 1995-2006). Tumor STAS was defined as tumor cells-micropapillary structures, solid nests, or single cells-spreading within air spaces in the lung parenchyma beyond the edge of the main tumor. Competing risks methods were used to estimate risk of disease recurrence and its associations with clinicopathological risk factors. STAS was observed in 155 cases (38%). In the limited resection group (n = 120), the risk of any recurrence was significantly higher in patients with STAS-positive tumors than that of patients with STAS-negative tumors (5-year cumulative incidence of recurrence, 42.6% versus 10.9%; P < 0.001); the presence of STAS correlated with higher risk of distant (P = 0.035) and locoregional recurrence (P = 0.001). However, in the lobectomy group (n = 291), the presence of STAS was not associated with either any (P = 0.50) or distant recurrence (P = 0.76). In a multivariate analysis, the presence of tumor STAS remained independently associated with the risk of developing recurrence (hazard ratio, 3.08; P = 0.014). The presence of STAS is a significant risk factor of recurrence in small lung adenocarcinomas treated with limited resection. These findings support our proposal that STAS should formally be recognized as a pattern of invasion in lung adenocarcinoma.

Clinicopathological analysis of 80 patients with duodenum gastrointestinal stromal tumors

To explore the clinicopathological characteristics, efficacy, and prognostic factors for patients with duodenum gastrointestinal stromal tumor(GIST). Clinicopathological and follow-up data of 80 patients with duodenum GIST in the Zhongshan Hospital from January 2000 to December 2013 were analyzed retrospectively. There were 38 male and 42 female patients with a median age of 54 years. The major symptoms were upper alimentary tract hemorrhage and abdominal pain. Thirty-nine patients received local tumor excision, 18 patients underwent segmental duodenectomy, 23 patients were subjected to pancreaticoduodenectomy, all these operations were R0 resection. Thirty patients received imatinib treatment after operation, and 11 among them had metastasis relapse. Recurrence-free survival rates of 1-, 3-, and 5-years were 96.2%, 90.6%and 78.6% retrospectively. Overall survival rates of 1-, 3-, and 5-years were 100%, 98.3% and 96.1%. Multivariate Cox analysis showed tumor size >5 cm, mitotic count >5 mitosis/50 HPF and intermediate/high NIH risk classification were associated with an increased risk of recurrence. The significant difference was not detected between the limited resection group and pancreaticoduodenectomy group in OS and RFS. Surgery is still the main treatment for duodenum GIST. The surgical program is mainly determined by the location and size of tumor. Imatinib therapy should be used if necessary.

Lung Cancer, Histologic Stratification, and Resection Extent: Something for Surgeons to Think About

You would think that thoracic surgeons have plenty to consider when planning for a lung cancer resection in 2013. We have been bombarded with “the small nodule” less than 2 mm, which we have learned can have various inhomogeneities in its computerized tomographic (CT) analysis (1); we have to decide whether the nodule merits a lobectomy (the standard of care) or a sublobar resection (2) (for those heretics in the minority who feel that we don’t need a randomized trial to answer the sublobar vs lobectomy debate); whether we should mark the nodule preoperatively so we will be able to find it because we are sometimes trying to feel a 2-cm sponge within a giant sponge; and whether to perform the case as a video-assisted resection, a robotic resection, or (shudder) as an open procedure with rib resection/spreading. As if those deliberations were not enough, now we must start to worry about whether the (presumed lung cancer) solid or part-solid nodule presented to us on the CT scan has a critical quantifiable element of micropapillary disease, which may be associated with tumor recurrence if we do a wedge resection or a segmentectomy (which, of course, will only be the standard of care for intentional lung cancer resections if this is confirmed by the results of CALGB 140503 “A Phase III Randomized Trial of Lobectomy Versus Sublobar Resection for Small (<2 cm) Peripheral Non–Small Cell Lung Cancer” (3). The article by Nitadori et al. (4) in this issue of the Journal is a continuation of the milestone publications by the International Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society, which have revolutionized the pathologic classification of lung adenocarcinoma (5). As reviewed by Suh (6), the new classification eliminates the categories of bronchioloalveolar carcinoma and mixed subtype adenocarcinoma to achieve precise correlations between predominant histologic subtypes of lung adenocarcinoma and survival in surgically resected patients. The Nitadori et al. article (4) retrospectively analyzed 476 lobectomies and 258 limited resections (either by wedge resection or anatomic segmentectomy) at a single institution in patients with lung adenocarcinomas of 2 cm or less. An important validation of the prognostic importance of the new classification system was demonstrated in the patients who had lobectomies for these small tumors; however, this was not seen in the limited resection group. Why is this? Is it because of the heterogeneity of the procedures performed? Is it because of the absence of clear-cut large margins? There are some other intriguing aspects of the limited resection group in these patients that also should be mentioned. The authors specify that the limited resection group is a combination of compromised (77.1%) patients and patients having intentional resection by less than a lobectomy (22.9%). The literature has documented that wedge resections performed in this population have a substantially higher incidence of local recurrence (7,8); yet, in this series the wedge resections (which were 2.6-fold more frequent than segmentectomies) did not reach statistical significance with regard to the cumulative incidence of recurrences compared with segmentectomies. One could speculate that this lack of recurrences in the wedge resection group was because of larger than average margins taken at the time of resection; however, another interesting finding in this series is that the size of the margin in the sublobar resection group did not influence the cumulative incidence of recurrence. This lack of margin size influence is also disturbingly different from publications com

Clinical, Pathological and Surgical Characteristics of Duodenal Gastrointestinal Stromal Tumor and Their Influence on Survival: A Multi-Center Study

The duodenum is a rare site of primary gastrointestinal stromal tumor (GIST). Overall (OS) and disease-free survival (DFS) after limited resection (LR) versus pancreaticoduodenectomy (PD) were studied. All patients who underwent surgery for primary, localized duodenal GIST between 2000 and 2011 were identified from four prospective institutional databases. OS and DFS were calculated by Kaplan-Meier method. Univariate analysis was performed. Eighty-four patients (median follow-up 42 months) underwent LR (n = 56, 67%) or PD (n = 28, 33%). Patients in the PD group had a larger median tumor size (7 cm vs. 5 cm, p = 0.024) and higher mitotic count (39% vs. 19% >5/50 high-power fields, p = 0.05). Complications were observed in five patients (9%) in the LR group and ten patients (36%) in the PD group. OS and DFS for the entire cohort were 89% and 64% at 5 years, respectively. No difference in outcome between LR and PD were observed. Eleven patients were treated with preoperative IM. A major RECIST response was obtained in nine (80%), whereas two had stable disease. Twenty-three patients received postoperative Imatinib (IM). A trend toward a better OS in IM-treated patients could be detected only in the high-risk group. Type of duodenal resection does not impact outcome. The choice should be determined by duodenal site of origin and tumor size. IM may be considered in cases at high risk of recurrence; in neoadjuvant setting, IM might facilitate resection and possibly increase the chance of preserving normal biliary and pancreatic anatomy.

How Radical Should Surgery Be for Early Esophageal Cancer?

We have compared the oncologic effectiveness of limited resection (LR) techniques such as transhiatal (TH) or limited resection of the esophagogastric junction with intestinal interposition (LREGJ) in the treatment of early esophageal carcinoma with that of the extended resection such as the classical thoracoabdominal (TA) en bloc esophagectomy. We performed a retrospective analysis of prospectively collected data of 113 patients with T1 esophageal cancer (57 adeno- and 56 squamous cell carcinomas) who had surgical resection with systematic lymphadenectomy. Forty-one underwent extensive (TA) and 72 limited resection (51 TH and 21 LREGJ). Complete resection (R0) was achieved in all cases. Lymphatic metastases were seen in none of the mucosal but in 26.8% of the submucosal T1 cancers. The median lymph node yield was significantly higher in patients with extensive resection (24 vs. 15 lymph nodes; p=0.036), but this did not affect the overall survival (median=88 vs. 102 months, 5-year survival probability=57.8 vs. 67.7%; log rank=0.578). The median hospital stay and ICU stay were significantly shorter in the LR group (p=0.039 and p = 0.044, respectively). Limited resection leads to lower lymph node yield but similar oncologic effectiveness as the extensive surgery. It may represent a valuable alternative in the treatment of patients with early (submucosal) esophageal carcinoma.