T1N0 Non-small Cell Lung Cancer Research Articles

Recurrence of Non–Small Cell Lung Cancer With Visceral Pleural Invasion

The randomized clinical trial Cancer and Leukemia Group B (CALGB) 140503 showed that for patients with clinically staged T1N0 non-small cell lung cancer (NSCLC; ≤2 cm), sublobar resections were associated with similar oncological outcomes to those after lobar resection. The association of the extent of parenchymal resection with recurrence and survival in patients with tumors pathologically upstaged to T2 based on visceral pleural invasion (VPI) is controversial. To determine survival and recurrence rates in patients with small peripheral pT2 NSCLC (≤2 cm) that was treated by either lobar or sublobar resection in CALGB 140503. CALGB 140503, a randomized multicenter noninferiority trial, included 697 patients with small peripheral NSCLC that was clinically staged as T1N0. Enrollment was from June 2007 through March 2017 at 83 participating institutions, and after a median follow-up of 7 years, the primary outcome of disease-free survival after sublobar resection was noninferior to that after lobar resection. Lobar or sublobar resection. Survival end points were estimated by the Kaplan-Meier estimator. Hazard ratios and 95% CIs were estimated using stratified Cox proportional hazard models. Of 679 participants, 390 (57.4%) were female, and the median (range) age was 67.8 (37.8-89.7) years. Among 697 patients randomized, 566 (81.2%) had pT1 tumors (no VPI) and 113 (16.2%) had pT2 tumors (VPI). Five-year disease-free survival was 65.9% (95% CI, 61.9%-70.2%) in patients with pT1 compared with 53.3% (95% CI, 44.3%-64.1%) in patients with pT2 tumors (stratified log-rank: P = .02). Disease recurrence developed in 27.6% of patients with pT1 (locoregional only: 60 [10.8%]; distant only: 81 [14.6%]) and 41.6% of those with pT2 (locoregional only: 17 [15.0%]; distant only: 27 [23.9%]). Five-year recurrence-free survival was 73.1% (95% CI, 69.2%-77.1%) for pT1 tumors and 58.2% (95% CI, 49.2%-68.8%) for pT2 tumors (stratified log-rank: P = .01). There were no intergroup differences in disease-free or recurrence-free survival based on the extent of parenchymal resection. The results of this secondary analysis suggest that compared with patients with tumors without VPI, patients who had tumors with VPI had worse disease-free and recurrence-free survival and a higher rate of local and distant disease recurrence. These high rates of recurrence were independent of the extent of parenchymal resection, and these data support the inclusion of these patients in adjuvant therapy trials. ClinicalTrials.gov Identifier: NCT0049933.

Stereotactic Radiation Therapy in Early Non–Small Cell Lung Cancer and Interstitial Lung Disease

Patients with interstitial lung disease (ILD) and early-stage non-small cell lung cancer (NSCLC) have been reported to be at high risk of toxic effects after stereotactic ablative radiotherapy (SABR), but for many patients, there are limited alternative treatment options. To prospectively assess the benefits and toxic effects of SABR in this patient population. This prospective cohort study was conducted at 6 academic radiation oncology institutions, 5 in Canada and 1 in Scotland, with accrual between March 7, 2019, and January 12, 2022. Patients aged 18 years or older with fibrotic ILD and a diagnosis of T1-2N0 NSCLC who were not candidates for surgical resection were enrolled. Patients were treated with SABR to a dose of 50 Gy in 5 fractions every other day. The study prespecified that SABR would be considered worthwhile if median overall survival-the primary end point-was longer than 1 year, with a grade 3 to 4 risk of toxic effects less than 35% and a grade 5 risk of toxic effects less than 15%. Secondary end points included toxic effects, progression-free survival (PFS), local control (LC), quality-of-life outcomes, and changes in pulmonary function. Intention-to-treat analysis was conducted. Thirty-nine patients enrolled and received SABR. Median age was 78 (IQR, 67-83) years and 59% (n = 23) were male. At baseline, 70% (26 of 37) of patients reported dyspnea, median forced expiratory volume in first second of expiration was 80% (IQR, 66%-90%) predicted, median forced vital capacity was 84% (IQR, 69%-94%) predicted, and median diffusion capacity of the lung for carbon monoxide was 49% (IQR, 38%-61%) predicted. Median follow-up was 19 (IQR, 14-25) months. Overall survival at 1 year was 79% (95%, CI 62%-89%; P < .001 vs the unacceptable rate), and median overall survival was 25 months (95% CI, 14 months to not reached). Median PFS was 19 months (95% CI, 13-28 months), and 2-year LC was 92% (95% CI, 69%-98%). Adverse event rates (highest grade per patient) were grade 1 to 2: n = 12 (31%), grade 3: n = 4 (10%), grade 4: n = 0, and grade 5: n = 3 (7.7%, all due to respiratory deterioration). In this trial, use of SABR in patients with fibrotic ILD met the prespecified acceptability thresholds for both toxicity and efficacy, supporting the use of SABR for curative-intent treatment after a careful discussion of risks and benefits. ClinicalTrials.gov Identifier: NCT03485378.

EP05.03-001 Impact of Neoadjuvant Chemo/radiotherapy Followed by Surgical Resection on T4N0-1 Non-Small Cell Lung Cancer

Despite many improvements in thoracic surgery and oncology, the best treatment strategy for T4 non-small cell lung cancer(NSCLC) is yet to be identified. However, select patients without N2/N3 disease have been shown to be benefited from surgical resection. We aim to determine the impact of neoadjuvant chemotherapy and/or high-dose radiation therapy on survival in patients with T4N0-1 non-small cell lung cancer.

MA04.09 The Incidence and Predictors of Unsuspected Brain Metastases in Patients with Stage IA NSCLC

Pretreatment evaluation for brain metastases with brain MRI is not routinely recommended for patients diagnosed with clinical T1N0 non-small cell lung cancer (NSCLC). However, the incidence of brain metastases in this patient population is not well known. In this study, we used two large U.S. clinical databases to examine the incidence and predictors of brain metastases among patients with stage IA NSCLC.

Therapeutic Bronchoscopy for Lung Nodules: Where Are We Now?

Lobar resection has been the established standard of care for peripheral early-stage non-small cell lung cancer (NSCLC). Over the last few years, surgical lung sparing approach (sublobar resection [SLR]) has been compared with lobar resection in T1N0 NSCLC. Three nonsurgical options are available in those patients who have a prohibitive surgical risk, and those who refuse surgery: stereotactic body radiotherapy (SBRT), percutaneous ablation, and bronchoscopic ablation. Local ablation involves placement of a probe into a tumor, and subsequent application of either heat or cold energy, pulsing electrical fields, or placement of radioactive source under an image guidance to create a zone of cell death that encompasses the targeted lesion and an ablation margin. Despite being in their infancy, the bronchoscopic ablative techniques are undergoing rapid research, as they extrapolate a significant knowledge-base from the percutaneous techniques that have been in the radiologist's armamentarium since 2000. Here, we discuss selected endoscopic and percutaneous thermal and non-thermal therapies with the focus on their efficacy and safety.

Risk stratification and adjuvant chemotherapy after radical resection based on the clinical risk scores of patients with stage IB-IIA non-small cell lung cancer

IntroductionDespite the heterogeneity among patients with stage IB-IIA non-small cell lung cancer (NSCLC), clinically applicable models to identify patients most suitable for receiving adjuvant chemotherapy (ACT) are limited. We aimed to develop a model for risk stratification and the individualized application of ACT. MethodsBetween January 2008 and March 2018, patients with T2N0M0 NSCLC at Sun Yat-sen University Cancer Center were retrospectively enrolled. Survival curves were estimated by Kaplan-Meier method and compared with log-rank test. Cox regression models were used to identify prognostic factors for disease-free survival (DFS) and overall survival (OS). Propensity score matching (PSM) was implemented. Subgroup analysis was performed based on clinical risk score (CRS) value and epidermal growth factor receptor (EGFR) mutation status. ResultsOf 1063 patients with T2N0 NSCLC enrolled, 272 patients received ACT. Before PSM, patients with high CRS (>1) had a significantly worse OS and DFS outcomes. In the PSM, the baseline characteristics of the 270 pairs of patients were well matched. ACT was associated with improved OS outcomes for patients with a high CRS, while ACT was associated with improved OS and DFS outcomes in patients with wild-type EGFR. The interaction analysis showed an apparent interaction effect between ACT and EGFR-activating mutations as well as chemotherapy regimens and histology. ConclusionsThe CRS can predict the prognosis of patients with stage IB-IIA NSCLC. ACT could improve the outcome of patients with a high CRS. Patients with non-squamous cell histology receiving pemetrexed plus platinum might benefit more, but not those with EGFR-activating mutations.

Significance of Brain Imaging for Staging in Patients With Clinical Stage T1-2 N0 Non–Small-Cell Lung Cancer on Positron Emission Tomography/Computed Tomography

BackgroundRoutine positron emission tomography/computed tomography (PET/CT) has been recommended even for clinical stage I non–small-cell lung cancer (NSCLC). In spite of the progress in the screening procedure, and revisions to TNM classification, there is no evidence to support brain imaging screening of patients assessed with the current staging protocol including PET/CT. Materials and MethodsWe retrospectively investigated the frequency of extrathoracic metastasis in 466 consecutive patients with clinical stage T1-2 N0 NSCLC with the complete staging assessment comprised of thin-section CT, PET/CT, and brain contrast-enhanced magnetic resonance imaging between 2008 and 2016. All patients were reclassified according to the eighth edition of the tumor, node, and metastasis (TNM) classification. ResultsAmong all patients, 70% of the tumors were pure solid and 30% had part-solid ground-glass opacity on thin-section CT, and 388 (83%) and 78 (17%) were classified into clinical stages T1 and T2, respectively. Eight patients (1.7%) had extrathoracic metastasis, including 3 (0.6%) with brain metastasis, and all showed pure-solid tumors. The frequency of extrathoracic and brain metastasis was 1.0% and 0.5% in 388 T1 patients, and 5.0% and 3.0% in 78 T2 patients. Although brain metastases were detected in 2 of 7 patients (29%) with PET/CT detectable extrathoracic metastases and 1 of 459 patients (0.2%) without PET/CT detectable extrathoracic metastasis, there were no neurologically asymptomatic brain metastases in patients with early-stage NSCLC confirmed by PET/CT. ConclusionRoutine screening of brain imaging is unnecessary in patients with early-stage NSCLC, assessed with the current staging protocol including PET/CT.

Significance of accurate hilar and intrapulmonary lymph node examination and prognostication in stage IA\u2013IIA non-small cell lung cancer, a retrospective cohort study

BackgroundThe examination of lymph nodes (LNs) plays an important role in the nodal staging of non-small cell lung cancer (NSCLC). For patients without LN metastasis, the main role of thorough LN examination is accurate staging, which weakens the effect of staging migration. To date, the role of hilar and intrapulmonary (N1) station LNs has not been fully appreciated. In this study, we aimed to confirm the significance of N1 LNs in long-term survival for stage IA–IIA NSCLC patients and to find the minimum number of LN to examine.MethodsThe data of patients who underwent radical lobectomy and were confirmed as having non-metastatic LNs from January 2008 to March 2018 were retrospectively screened. Pathology records were reviewed for the number of LNs examined. The Kaplan-Meier method and Cox regression model were used to identify survival and prognostic factors.ResultsThe median number of resected N1 LNs was 8. The number of patients with 0–2 N1 LNs, 3–5 N1 LNs, 6–8 N1 LNs, 9–11 N1 LNs, and more than 11 N1 LNs examined was 181, 425, 477, 414, and 531, respectively. Sex (P = 0.004), age (P < 0.001), tumor size (P = 0.004), differentiation degree (P = 0.001), and number of N1 LNs examined (P = 0.008) were independent prognostic factors of overall survival. Gender (P = 0.006), age (P = 0.031), tumor size (P = 0.001), differentiation degree (P = 0.001), vascular invasion (P = 0.034), and number of N1 LNs examined (P = 0.007) were independent prognostic factors of disease-free survival. Compared with patients with 0–5 N1 LNs examined, patients with more than 5 N1 LNs examined had better OS (P = 0.015) and had better DFS (P = 0.015) if only a landmark 5-year follow-up was performed.ConclusionIncreasing the number of N1 LN examination might improve the long-term survival of T1-2N0 NSCLC patients. These data indicate that at least 6 N1 nodes examined is an essential part in surgical and pathological management but cannot prove this. This finding should be confirmed in a large, prospective randomized clinical study.

Spontaneous regression of ALK fusion protein-positive non-small cell lung carcinoma: a case report and review of the literature

BackgroundALK-rearrangement is observed in < 5% non-small cell lung cancer (NSCLC) cases and prior to the advent of oral tyrosine kinase inhibitors, the natural history of oncogenic NSCLC was typically poor. Literature relating to regression of treatment-naïve NSCLC is limited, and regression without treatment has not been noted in the ALK-rearranged sub-population.Case presentationA 76 year old ‘never smoker’ female with an ALK-rearranged left upper lobe T2 N0 NSCLC experienced a stroke following elective DC cardioversion for new atrial fibrillation. Following a good recovery, updated imaging demonstrated complete regression of the left upper lobe lesion and a reduction of the previously documented mediastinal lymph node. Remaining atelectasis was non-avid on repeat PET-CT imaging, 8 months from the baseline PET-CT. When the patient developed new symptoms 6 months later a further PET-CT demonstrated FDG-avid local recurrence. She completed 55 Gy in 20 fractions but at 18 months post-radiotherapy there was radiological progression in the lungs with new pulmonary metastases and effusion and new bone metastases. Owing to poor performance status, she was not considered fit for targeted therapy and died 5 months later.ConclusionAll reported cases of spontaneous regression in lung cancer have been collated within. Documented precipitants of spontaneous regression across tumour types include biopsy and immune reconstitution; stroke has not been reported previously. The favourable response achieved with radical radiotherapy alone in this unusual case of indolent oncogenic NSCLC reinforces the applicability of radiotherapy in locally advanced ALK-rearranged tumours, in cases not behaving aggressively. As a common embolic event affecting the neurological and pulmonary vasculature is less likely, an immune-mediated mechanism may underpin the phenomenon described in this patient, implying that hitherto unharnessed principles of immuno-oncology may have relevance in oncogenic NSCLC. Alternatively, high electrical voltage applied percutaneously adjacent to the tumour during cardioversion in this patient may have induced local tumour cell lethality.

Recurrence After Stereotactic Body Radiation Therapy Versus Lobectomy for Non-Small Cell Lung Cancer

Although lobectomy remains the standard of care for early-stage non-small cell lung cancer, several studies suggest equipoise between lobectomy and stereotactic body radiation therapy (SBRT). However randomized evidence is lacking. We compared outcomes of early-stage non-small cell lung cancer patients treated with lobectomy or SBRT. We included clinical T1-2N0 non-small cell lung cancer treated with lobectomy or SBRT to a biologically effective dose of ≥100 Gy10. We used Cox proportional hazards and nearest-neighbor propensity score (2:1) matching to adjust for confounders. Kaplan-Meier curves were used to assess survival and recurrence. We identified 554 patients treated with lobectomy (n= 389) or SBRT (n= 165) at our institution between 2008 and 2018. After propensity score matching, there were 132 SBRT patients and 85 lobectomy patients. SBRT was associated with increased local recurrence (hazard ratio [HR], 6.80; 95% confidence interval [CI], 1.92-24.10; P= .003) and regional nodal recurrence (HR, 2.58; 95% CI, 1.17-5.68; P= .018), and with worse overall survival (HR, 2.00; 95% CI, 1.21-3.32; P= .007) and progression-free survival (HR, 2.34; 95% CI, 1.50-3.67; P<.001). There was no difference in distant recurrence (HR, 1.19; 95% CI, 0.57-2.52; P= .64). We found superior outcomes in patients with early-stage non-small cell lung cancer treated with lobectomy compared with SBRT, including locoregional control. These findings should be interpreted with caution because of selection bias but underscore the importance of robust randomized prospective data to clarify the relative efficacy of these modalities.

Risk Factors for Occult Lymph Node Metastasis in Peripheral Non-Small Cell Lung Cancer with Invasive Component Size 3cm or Less.

In the seventh edition TNM staging system for lung cancer, a high maximum standardized uptake value (SUVmax) on positron emission tomography was regarded as a risk factor for occult lymph node metastasis in clinical T1N0 non-small cell lung cancer (NSCLC). However, in the eighth edition TNM classification, tumors are classified according to the size of the invasive component only, and those with invasive component size ≤3cm are diagnosed as stage T1. The aim of this study was to reassess the risk factors for occult lymph node metastasis under the eighth edition TNM classification for lung cancer. From 2010 to 2017, 553 patients with clinical N0 peripheral NSCLC with invasive component size ≤3cm underwent anatomical lobectomy with systematic lymph node dissection. We analyzed these cases retrospectively to identify risk factors for postoperative nodal upstaging. Among 553 study patients, 54 (9.8%) had nodal upstaging after surgery. In multivariate analysis adopting the eighth edition TNM classification for lung cancer, serum carcinoembryonic antigen (CEA) level (hazard ratio [HR] = 1.113, p = 0.002), invasive component size (HR = 2.398, p = 0.004), visceral pleural invasion (HR = 2.901, p = 0.005), and lymphatic invasion (HR = 9.336, p < 0.001) were significant risk factors for nodal upstaging, but SUVmax was not. SUVmax is not a predictor of nodal upstaging in clinical N0 peripheral NSCLC with invasive component size ≤3cm under the eighth edition TNM classification for lung cancer. Significant risk factors of occult lymph node metastasis are serum CEA level, tumor invasive component size, visceral pleural invasion, and lymphatic invasion.

MS07.04 Stage I (Resectable) NSCLC: Surgery

MS07.04 Stage I (Resectable) NSCLC: Surgery

Invasive Nodal Staging May Not Reduce Regional and Distant Recurrence Rates for Patients Treated with SBRT for Inoperable Stage I NSCLC

In patients receiving definitive stereotactic body radiation therapy (SBRT) for presumably node-negative, early-stage non-small cell lung cancer (NSCLC), many patients are staged with PET-CT alone. The role of invasive nodal staging with either bronchoscopy plus endobronchial ultrasound (EBUS) or mediastinoscopy in patients undergoing PET prior to definitive lung SBRT is uncertain. We sought to characterize the impact of nodal staging modality on clinical outcomes after SBRT for early NSCLC. Patients receiving definitive SBRT for T1-2N0 NSCLC that were determined to be node-negative by either PET plus invasive nodal staging (EBUS or mediastinoscopy) or PET alone were identified using a single-institution prospective registry. All patients received 3-5 fraction SBRT with a biologically effective dose (BED10) of ≥ 100 Gy. Patients who did not undergo pre-SBRT PET, received adjuvant systemic therapy, or who were treated with additional SBRT courses for synchronous or metachronous NSCLC were excluded from the current study. Multivariable logistic regression was performed to identify which variables were independently associated with invasive mediastinal staging. Variables evaluated included staging, age, gender, ethnicity, central versus peripheral location, stage, and histology. A total of 651 patients treated from 2005 – 2016 met the above inclusion criteria. Invasive nodal staging was performed in 15.2% of patients (n=99) with either EBUS (n= 78) or mediastinoscopy (n= 21). Median age at SBRT was 75.3 years (range, 49.3 – 88.8). Median follow up was 19.4 months, and median survival was 28.5 months for all patients. Factors predictive of increased likelihood to receive invasive nodal staging on multivariable analysis were young age (OR for increasing age 0.968; 95% CI 0.945 – 0.990), white race (OR for non-white 0.540; 0.304 = 0.958), female patients (OR 1.629; 95% CI 1.031 – 2.575), central location (OR 1.978; 95% CI 1.218 – 3.211) and squamous histology (OR 2.564; 95% CI 1.243 – 5.287). On multivariable analysis, nodal and/or distant failure was not significantly different between PET alone (crude failure rate, 23.6%) versus invasive nodal staging (25.4%, p=0.714) in this patient cohort. Most patients with early stage NSCLC treated with definitive SBRT did not undergo invasive nodal staging, and we identify several factors predictive of its use. There was no significant difference in nodal or distant failure based on type of nodal staging utilized.

Treatment of T3N0 Non-Small Cell Lung Cancer with Chest Wall Invasion Using Stereotactic Body Radiotherapy

Treatment of T3N0 Non-Small Cell Lung Cancer with Chest Wall Invasion Using Stereotactic Body Radiotherapy

Stereotactic Ablative Radiation Therapy Achieves Excellent Outcomes for Elderly Patients with Bulky Early-Stage Non-Small-Cell Lung Cancer

Precision Stereotactic Body Radiotherapy (SBRT) delivers ablative doses to a target, while minimising the dose to surrounding critical organs. While the use of SBRT has been well established in early stage non-small cell lung cancer (NSCLC), concerns about toxicity and tolerability have limited its use or led to a reduction in prescribed dose in the elderly population, particularly when larger lesions are treated. We hypothesize that SBRT given to the elderly (defined as ≥65 yo and above) patient with a larger T2 and above lesion is safe and offers effective disease control in a population who is otherwise not fit for surgical resection. To investigate this, we performed a retrospective review of treatment outcomes for patients ≥65 yo with biopsy proven and PET staged T2 N0 and T3 N0 NSCLC who received lung SBRT in our centre from 2009 to 2017. 1 patient who had no follow-up imaging was excluded. To account for different dose fractionations, all doses were converted into biological equivalent doses (BED) using an α/ßTumor = 10. Response to treatment was assessed on serial CT imaging performed ever 3-4 mo, using RECIST criteria and toxicities were prospectively recorded using CTCAEv4. Kaplan-Meier was performed and survival outcomes compared using log-rank test. We identified a total of 25 patients with a median age of 76.8yo (IQR: 72.2 – 79.9yo). 18 (72%) were deemed medically inoperable while 7(28%) declined surgery. Median GTV-ITV was 24.9cc (19.2 – 38.6cc) and median PTV was 64cc (50.5 – 83.6cc). Median D95 BED10 was 94.5 (94.1 – 132.3) with a median D10 BED10 of 113.81 (102.7 – 146.9). 4 patients relapsed in-field, representing a 2y and 3y target control of 88.2% and 80.9% respectively; 2 target failures developed distant failures at the same time. 2y and 3y control rates were 91.3% and 84.8% [same lobe], 83.3% and 70.9% [Nodal], 83.3% and 70.9% [Ipsilateral lung] and 80.1% and 65.8% [distant] respectively. 2y and 3y survival rates were 74.6% and 49.7% [overall, OS] and 86.3% and 67.8% [cancer specific, CSS]. In our cohort, a D95 BED10≥100Gy was not associated with improved target control or OS. SBRT in this population was well tolerated with 1(4%) patient reporting grade 3 pneumonitis. Despite significant chest wall doses [median V30: 52.8cc, 26.1 – 70.7cc], only one patient had a rib fracture. Another patient died 1 week following SBRT but this was attributed to a flare of his pneumonia and COPD post RT. Interestingly, poorer OS was observed in patients with significant interstitial scarring post SBRT (46mo [scarring] vs 68.8mo [no scarring]; p = 0.165). Herein, our data demonstrates excellent outcomes in elderly patients with bulky T2 N0 and above NSCLC treated with SBRT.

Marginal Failures with Stereotactic Body Radiation Therapy(SBRT) for Early Stage Lung Cancer: Room for Improvement?

SBRT is an effective treatment for early stage non-small cell lung cancer (NSCLC). Prior series distinguish local from regional/distant recurrences, but detailed patterns of local failure are not well-described. We evaluate the location of local failures to provide further insight for treatment planning. Patients treated with SBRT for T1-2N0 NSCLC from 2007-2016 at a single institution were included. Prescribed dose was 48-54Gy in 3 to 5 fractions and planning target volume (PTV) margins were generally 5mm radially and 8mm superior/inferior. Site of first failure was classified as local, regional (hilar/mediastinal lymph nodes) or metastatic. For patients with a component of local failure, post-treatment diagnostic scans at time of recurrence were fused to the initial planning scan using rigid registration to lung features proximal to recurrence. The recurrence volume was delineated and compared to the treatment PTV. For each local failure, percent overlap of the PTV and recurrence volume was calculated. Distance from centroid (geometric center) of recurrence to PTV edge was measured in 3 planes and average distance was calculated. Local failures were categorized as: in-field failure (≥80% overlap or centroid >1cm inside PTV), marginal failure (20-80% overlap and centroid <1 cm inside/outside PTV), or involved lobe failure (overlap <20% or centroid >1cm outside PTV). Parametric statistics compared characteristics of recurrences. A total of 217 patients were treated with robotic radiosurgery (94%) or linac-based (6%) SBRT. 83% were T1 tumors, 69% upper lobe tumors, and 74% biopsy-proven malignancy. With a median follow-up of 20 months (range 0-98), 38% had progression of disease. 16% (N=34) had a component of local progression at time of first failure: 18 local only, 8 locoregional, 8 metastatic. 60% were pathologically confirmed. Of the local failures, 9 were classified as in-field, 15 marginal and 10 involved lobe. For in-field, marginal, and involved lobe failures there were differences in mean PTV/recurrence overlap (93% vs 43% vs 2%) and distance from centroid to PTV margin (1.39cm vs 0.56cm vs 1.78cm). For all local failures, PTV D95 was at least prescription dose. Marginal failures developed earlier than other local failures (mean 15 vs 25 months, p<0.05). Upper and lower lobe tumors had similar rates of local failure (16% vs 18%); however, 8 of the 11 local failures seen in lower lobe tumors were marginal failures compared to only 7 of 23 local failures in upper lobe tumors. Local progression is seen in roughly 16% of patients following SBRT. Marginal failures represent nearly half of these events, and appear to be of particular concern for lower lobe tumors. These findings highlight an opportunity to further evaluate margin size, motion management, and accuracy of dose calculations at the PTV margin to further improve local control in lung SBRT.

Lymphovascular Invasion Increases the Risk of Nodal and Distant Recurrence in Node-Negative Stage I–IIA Non-Small-Cell Lung Cancer

Objectives: Despite complete surgical resection, 30–40% of patients with stage I–IIA non-small-cell lung cancer (NSCLC) have recurrences. We aimed to elucidate the effect of lymphovascular invasion (LVI) on the prognosis and patterns of recurrence in patients with pathologically confirmed T1–2N0 NSCLC. Methods: We evaluated 381 patients who underwent complete resection and were diagnosed with pathologic T1–2N0 NSCLC between March 2000 and January 2012. Local recurrence, nodal recurrence, and distant metastasis were defined and analyzed. Results: LVI was present in 72 patients (18.9%). The 5-year disease-free survival (DFS) for all patients was 69.9%. Patients with LVI showed a significant decrease in 5-year DFS (47.3 vs. 74.4%, p < 0.001). LVI was a significant prognostic predictor in multivariate analysis (p = 0.003). The patients with LVI showed a significantly increased 5-year cumulative incidence of nodal recurrence (22.5 vs. 8.7%, p < 0.001) and distant metastasis (30.4 vs. 14.9%, p = 0.004). However, no difference was shown between the two groups in the 5-year cumulative incidence of local recurrence (p = 0.416). Conclusions: LVI is a negative prognostic factor in patients with stage I–IIA NSCLC. The presence of LVI significantly increases the risk of nodal and distant recurrence.

Consolidation/Tumor Ratio on Chest Computed Tomography as Predictor of Postoperative Nodal Upstaging in Clinical T1N0 Lung Cancer.

In clinical T1N0 peripheral lung cancers, lymph node upstaging is occasionally encountered postoperatively. However, nodal upstaging is rare in lung cancers presenting as ground-glass opacities. The aim of this study was to determine if lymph node upstaging could be reliably extrapolated from parameters such the consolidation/tumor ratio of chest computed tomography. We conducted a retrospective study of 486 patients treated for peripheral clinical T1N0 non-small cell lung cancer, each undergoing lobectomy with mediastinal lymph node dissection. We compared preoperative variables in the pathologic N0 and nodal upstaging groups, analyzing such variables to determine factors predictive of lymph node upstaging. Of the 486 patients studied, lymph node upstaging occurred in 42 (8.6%). In the upstaging group, the mean nodule diameter exceeded that of the pathologic N0 group (2.3 vs 1.9cm, respectively; p<0.001), and the mean consolidation/tumor ratio was larger in the upstaging group than the pN0 group (0.95 vs 0.68, respectively; p<0.001). Nodule diameter and consolidation/tumor ratio emerged as significant predictive factors for lymph node upstaging after surgery in a multivariate analysis (hazard ratio [HR] 2.259, p=0.039; HR 173.645, p=0.001, respectively). Consolidation/tumor ratio and nodule diameter are significant predictive factors of postoperative lymph node upstaging. The higher the consolidation/tumor ratio and smaller the nodule diameter, the less likely the occurrence of postoperative lymph upstaging would be in clinical T1N0 peripheral non-small cell lung cancer.

P2.05-019 Overall Survival (OS) of Pathological T1N0 Non-Small Cell Lung Cancer (NSCLC) After Resection

P2.05-019 Overall Survival (OS) of Pathological T1N0 Non-Small Cell Lung Cancer (NSCLC) After Resection

Is left upper lobectomy always worthwhile for early stage lung cancer? A comparison between left upper lobectomy, trisegmentectomy, and lingulectomy

Lobectomy is the gold standard treatment for resectable Non-Small Cell Lung Cancer (NSCLC). We compared oncological outcomes of patients undergoing a "multi-segmentectomy" (trisegmentectomy or lingulectomy) and left upper lobectomy for early stage (T1-2, N0) NSCLC of the left upper lobe. We retrospectively analyzed all patients with pathological early stage (T1-T2 N0) NSCLC located in left upper lobe who underwent a lobectomy, a trisegmentectomy, or a lingulectomy between 2006 and 2013, focusing on surgical and oncological outcomes. Among 159 patients, 105 patients underwent a lobectomy and 54 patients a multi-segmentectomy (33 lingulectomy and 21 trisegmentectomy). Actuarial mean Overall Survival was 87 months (95%CI 79-95) and 89 months (95%CI 76-101) for lobectomies and multi-segmentectomies, respectively (P-value: 0.895), while actuarial mean Disease Free Interval was 91 months (95%CI 82-100) and 96 months (95%CI 84-108) respectively (P-value: 0.565). We did not observe any difference in terms of local recurrence rate between the two groups (P = 0.337). Lingulectomy and trisegmentectomy lead to similar oncological outcomes compared to left upper lobectomy for T1 and T2 N0 NSCLC, and they could be used as an alternative to lobectomy even in patients with a good pulmonary function.