Time-varying pattern of postoperative recurrence risk of early-stage (T1a-T2bN0M0) non-small cell lung cancer (NSCLC): results of a single-center study of 994 Chinese patients

Pathological Pleural Invasion is a Risk Factor for Late Recurrence in Long-Term Survivors of Non-small Cell Lung Cancer after Complete Resection

BACKGROUND

Information regarding late recurrence after pulmonary resection for non-small cell lung cancer (NSCLC) is limited. This study aimed to analyze the risk factors for late recurrence after surgery for NSCLC in the current era.

PATIENTS AND METHODS

We conducted a retrospective study of patients who underwent complete resection for pathological I-III NSCLC between 2006 and 2015. Late recurrence was defined as a recurrence that met the following conditions: (1) the patient underwent chest computed tomography (CT) at or after 54 months after surgery and recurrence was not detected at that time, and (2) recurrence that occurred more than 5 years after surgery. The factors influencing late recurrence, relapse-free survival (RFS), and overall survival (OS) after surgery were analyzed.

RESULTS

A total of 1275 with 5-year relapse-free survival after surgery were enrolled in this study. The mean age of the patients was 66.4 years and 54% of the patients were men. The median interval between surgery and the latest follow-up examination was 98 months. In total, 35 patients (2.7%) experienced late recurrence and 138 patients have died thus far. The cumulative recurrence, RFS, and OS rates at 10 years were 3.9%, 84.9%, and 86.3%, respectively. A multivariate analysis revealed that pleural invasion was an independent risk factor for late recurrence. Pleural invasion was a poor prognostic factor for both RFS and OS.

CONCLUSIONS

Pleural invasion was a predictor of late recurrence. Age > 67 years, preoperative serum carcinoembryonic antigen (CEA) > 5 ng/ml, non-adenocarcinoma, and pleural invasion were poor prognostic factors for RFS.

Comparison of radiotherapy versus surgical resection following neoadjuvant chemoimmunotherapy in potentially resectable stage III non-small-cell lung cancer: A propensity score matching analysis

BACKGROUND

Neoadjuvant chemoimmunotherapy followed by surgery is recommended for resectable non-small-cell lung cancer (NSCLC). However, a considerable proportion of patients do not undergo surgery and opt for alternative treatments such as radiotherapy. The efficacy of radiotherapy in this context remains unclear.

METHODS

This retrospective study analyzed data from patients with stage III NSCLC who received neoadjuvant chemoimmunotherapy followed by either surgery or radiotherapy. Propensity score matching (PSM) was used to balance the heterogeneity between the groups. Efficacy outcomes, safety profiles, and disease recurrence patterns were assessed.

RESULTS

In total, 175 patients were included; 50 underwent radiotherapy, and 125 underwent surgery. Prior to matching, radiotherapy was inferior to surgery in terms of progression-free survival (PFS; Hazard ratio [HR], 2.23; P = 0.008). Following a 1:1 PSM adjustment, each group consisted of 40 patients. The median PFS was 30.8 months in the radiotherapy group and not reached in the surgery group (HR, 1.46; P = 0.390). The 12- and 24-month PFS rates were 90.4 % and 69.0 % for the radiotherapy group compared to 94.1 % and 73.9 % for the surgery group, respectively. Subgroup analyses after PSM showed that patients with stage IIIA disease tend to benefit more from surgery than those with stage IIIB disease (HR, 3.00; P = 0.074). Grade 3-4 treatment-related adverse events (TRAEs) occurred in 62.5 % of patients in the radiotherapy group and 55.0 % in the surgery group, with no grade 5 TRAEs reported. The incidence of grade 3-4 treatment-related pneumonitis or pneumonia was 7.5 % and 2.5 % in the radiotherapy and surgery groups, respectively.

CONCLUSION

Radiotherapy may be a viable alternative to surgery in patients with resectable NSCLC who do not undergo surgical resection after initial neoadjuvant chemoimmunotherapy, offering comparable efficacy and a manageable safety profile. Larger prospective studies are needed to validate these findings and optimize the treatment strategies for this patient population.

Differential impact of intratumor heterogeneity (ITH) on survival outcomes in early-stage lung squamous and adenocarcinoma based on tumor mutational burden (TMB)

Background

Molecular biomarkers are reshaping patient stratification and treatment decisions, yet their precise use and best implementation remain uncertain. Intratumor heterogeneity (ITH), an area of increasing research interest with prognostic value across various conditions, lacks defined clinical relevance in certain non-small cell lung cancer (NSCLC) subtypes. Exploring the relationship between ITH and tumor mutational burden (TMB) is crucial, as their interplay might reveal distinct patient subgroups. This study evaluates how the ITH-TMB dynamic affects prognosis across the two main histological subtypes of NSCLC, squamous cell and adenocarcinoma, with a specific focus on early-stage cases to address their highly unmet clinical needs.

Methods

We stratify a cohort of 741 early-stage NSCLC patients from The Cancer Genome Atlas (TCGA) based on ITH and TMB and evaluate differences in clinical outcomes. Additionally, we compare driver mutations and the tumor microenvironment (TME) between high and low ITH groups.

Results

In lung squamous cell carcinoma (LUSC), high ITH predicts an extended progression-free survival (PFS) (median: 21 vs. 14 months, P=0.01), while in lung adenocarcinoma (LUAD), high ITH predicts a reduced PFS (median: 15 vs. 20 months, P=0.04). This relationship is driven by the low TMB subset of patients. Additionally, we found that CD8 T cells were enriched in better-performing subgroups, regardless of histologic subtype or ITH status.

Conclusions

There are significant differences in clinical outcomes, driver mutations, and the TME between high and low ITH groups among early-stage NSCLC patients. These differences may have treatment implications, necessitating further validation in other NSCLC datasets.

Liquid Biopsy in Lung Cancer: Biomarkers for the Management of Recurrence and Metastasis

Liquid biopsies have emerged as a promising tool for the detection of metastases as well as local and regional recurrence in lung cancer. Liquid biopsy tests involve analyzing a patient's blood, urine, or other body fluids for the detection of biomarkers, including circulating tumor cells or tumor-derived DNA/RNA that have been shed into the bloodstream. Studies have shown that liquid biopsies can detect lung cancer metastases with high accuracy and sensitivity, even before they are visible on imaging scans. Such tests are valuable for early intervention and personalized treatment, aiming to improve patient outcomes. Liquid biopsies are also minimally invasive compared to traditional tissue biopsies, which require the removal of a sample of the tumor for further analysis. This makes liquid biopsies a more convenient and less risky option for patients, particularly those who are not good candidates for invasive procedures due to other medical conditions. While liquid biopsies for lung cancer metastases and relapse are still being developed and validated, they hold great promise for improving the detection and treatment of this deadly disease. Herein, we summarize available and novel approaches to liquid biopsy tests for lung cancer metastases and recurrence detection and describe their applications in clinical practice.

Epidemiology, Patients’ Journey and Healthcare Costs in Early-Stage Non-Small-Cell Lung Carcinoma: A Real-World Evidence Analysis in Italy

This real-world analysis aims to estimate the epidemiology and economic burden related to early-stage non-small-cell lung carcinoma (eNSCLC) in the clinical practice Italian setting. An observational analysis was performed using administrative databases linked to pathological anatomy data, covering around 2.5 mln health-assisted individuals. From 2015 to mid-2021, eNSCLC patients staged II–IIIA treated with chemotherapy after surgery were included. Patients were stratified into those presenting loco-regional or metastatic recurrence during follow-up and annualized healthcare direct costs covered by the Italian National Health System (INHS) were estimated. In 2019–2020, the prevalence of eNSCLC was 104.3–117.1/million health-assisted subjects, and the annual incidence was 38.6–30.3/million. Data projected to the Italian population estimated 6206 (2019) and 6967 (2020) prevalent and 2297 (2019) and 1803 (2020) incident cases. Overall, 458 eNSCLC patients were included. Of them, 52.4% of patients had a recurrence (5% loco-regional-recurrence, 47.4% metastatic-recurrence). Healthcare total direct costs/patient averaged EUR 23,607, in particular, in the first year after recurrence, costs averaged EUR 22,493 and EUR 29,337 in loco-regional and metastatic-recurrence patients, respectively. This analysis showed that about one-half of eNSCLC patients stage II–IIIA experience a recurrence, and in recurrence patients, total direct costs were almost two-fold those of no-recurrence patients. These data highlighted an unmet clinical need, as the therapeutic optimization of patients at early stages.

Spread through air spaces is a powerful prognostic predictor in patients with completely resected pathological stage I lung adenocarcinoma

PURPOSE

To evaluate the frequency of spread through air spaces (STAS) in patients with early-stage primary lung cancer and to elucidate the association between STAS and various clinicopathological factors.

METHODS

We retrospectively reviewed data from a total of 265 consecutive patients who underwent lobectomy and mediastinal lymph node dissection (172 patients) or sublobar resection (93 patients) for completely resected pathological stage I lung adenocarcinoma. We evaluated clinical variables, including the preoperative serum carcinoembryonic antigen (CEA) level, tumour size, consolidation tumour ratio (CTR), maximum standardized uptake value (SUVmax) on FDG-PET, histological results, presence of STAS and vascular and lymphatic invasion.

RESULTS

The median follow-up time after surgery was 49 months. Eighty-seven patients (32.8 %) had STAS. The overall survival rates of patients in the STAS-positive and STAS-negative groups were 92.7 % and 97.1 % at 3 years, respectively (p = 0.1255), and the recurrence-free survival rates were 82.1 % and 95.9 % at 3 years, respectively (p = 0.0001). STAS was found in 73 patients (42.4 %) in the lobectomy group, which was a significantly higher proportion than the 14 patients (15.1 %) in the sublobar resection group. The STAS-positive group had significantly larger areas of invasion, higher CTRs, preoperative CEA and SUVmax levels, and more lymphatic and vascular invasion. STAS also correlated significantly with large consolidation sizes, larger invasive size, higher CTRs and the presence of a micropapillary pattern. Cox regression analysis after adjustment for important prognostic factors revealed that the presence of STAS was an independent predictor associated with postoperative recurrence, most of which was observed locoregionally.

CONCLUSIONS

STAS was an independent factor associated with postoperative recurrence after lung resection for stage I lung adenocarcinoma. Among stage IA patients, the postoperative outcomes of STAS-positive patients were worse than those of STAS-negative patients and were similar to those of stage IB patients.

Hazard Function Analysis of Recurrence in Patients with Curatively Resected Lung Cancer: Results from the Japanese Lung Cancer Registry in 2010

Simple Summary

To optimize postoperative surveillance of lung cancer patients, we investigated the hazard function of tumor recurrence in patients with completely resected lung cancer. Using the records of the 2010 Japanese Joint Committee of Lung Cancer Registry, the risk of postoperative recurrence was analyzed using a cause-specific hazard function in patients who underwent lobectomy to completely resect pathological stage I–III lung cancer. The hazard function for recurrence exhibited a peak at approximately 9 months after surgery, followed by a tapered plateau-like tail extending to 60 months. The peak risk for intrathoracic recurrence was approximately two-fold higher compared with that of extrathoracic recurrence. When considered together with the results of the subgroup analysis, the characteristics of the postoperative tumor recurrence hazard in a large cohort of lung cancer patients may be useful for improving stage-related management of postoperative surveillance.

Abstract

To optimize postoperative surveillance of lung cancer patients, we investigated the hazard function of tumor recurrence in patients with completely resected lung cancer. We analyzed the records of 12,897 patients in the 2010 Japanese Joint Committee of Lung Cancer Registry who underwent lobectomy to completely resect pathological stage I–III lung cancer. The risk of postoperative recurrence was determined using a cause-specific hazard function. The hazard function for recurrence exhibited a peak at approximately 9 months after surgery, followed by a tapered plateau-like tail extending to 60 months. The peak risk for intrathoracic recurrence was approximately two-fold higher compared with that of extrathoracic recurrence. Subgroup analysis showed that patients with stage IIIA adenocarcinoma had a continuously higher risk of recurrence compared with patients with earlier-stage disease. However, the risk of recurrence in patients with squamous cell carcinoma was not significantly different compared with that more than 24 months after surgery, regardless of pathological stage. In conclusion, the characteristics of postoperative tumor recurrence hazard in a large cohort of lung cancer patients may be useful for determining the time after surgery at which patients are at the highest risk of tumor recurrence. This information may improve stage-related management of postoperative surveillance.

Anesthetic and analgesic techniques and perioperative inflammation may affect the timing of recurrence after complete resection for non-small-cell lung cancer

Introduction

It has been widely recognized that both surgery and anesthesia may increase the risk of cancer recurrence by inducing an inflammatory response and immunosuppression in various cancer operations. The present study explored using hazard curves how anesthetic and analgesic techniques regarding the host inflammation status affect the risk of recurrence over time in patients with non-small-cell lung cancer (NSCLC).

Material and Methods

Clinicopathological data from patients who underwent complete pulmonary resection with pathological I–IIIB stage NSCLC from 2010 to 2020 were collected. The inflammation-based scores, including the C-reactive protein-to-albumin ratio (CAR), systemic immune-inflammation index (SII), Glasgow prognostic score (GPS), and modified GPS (mGPS), were calculated before surgery, and hazard curves indicating the changes in hazards over time were evaluated.

Results

A total of 396 patients were eligible for the analysis. The median follow-up was 42.3 months. In total, 118 patients (29.8%) experienced recurrence, and 66.9% of those occurred within 24 months after surgery. According to the multivariate Cox regression analysis, volatile anesthesia (VA) (hazard ratio [HR], 1.69; 95% confidence interval [CI], 1.05–2.71), and elevated CAR (HR, 1.88; 95% CI, 1.18–2.99) were associated with a worse recurrence-free survival. The resulting hazard curve revealed that a delayed peak of recurrence was present in patients with a low CAR in the VA group and in those with intravenous flurbiprofen axetil administration in the propofol-based total intravenous anesthesia group (30 and 24 months after surgery, respectively).

Discussion

Choosing anesthetic and analgesic techniques while taking inflammation-based scores into account may be useful for reducing the risk of and/or delaying recurrence in patients undergoing resection for NSCLC.

Prognosis and recurrence patterns in patients with early stage lung cancer: a multi-state model approach

Background

We aimed to assess whether recurrence patterns affect survival and to use a multi-state model to predict the prognosis of early stage non-small cell lung cancer in patients who underwent surgical resection.

Methods

Patients with early stage non-small cell lung cancer who underwent surgical resection at two tertiary medical centers between 2010 and 2015 were retrospectively analyzed. A multi-state model was employed with one initial state (surgery), two intermediate states (locoregional recurrence, distant metastasis), and one absorbing state (death), comprising five transitions: surgery to locoregional recurrence, surgery to distant metastasis, surgery to death without recurrence, locoregional recurrence to death, and distant metastasis to death. Cox proportional hazards models stratified for these transitions were performed with the risk factors; transition probabilities for each patient were predicted.

Results

A total of 949 patients were identified [median age: 67 years, male: 614 (64.6%)]. Recurrence occurred in 194 (20.4%) patients (locoregional recurrence: 7.3%, distant metastasis: 13.1%). Hazard ratios for distant metastasis after surgery were higher for older age (hazard ratio: 1.03, 95% confidence interval: 1.01-1.06) and adenocarcinoma (hazard ratio: 1.67, 95% confidence interval: 1.06-2.61). Lower lobe location exhibited a higher hazard ratio for death after surgery without recurrence (hazard ratio: 1.59, 95% confidence interval: 1.00-2.53). Stage IIB lung cancer showed a higher probability of transition to distant metastasis after surgery than other stages. Cumulative transition hazards rapidly increased in both recurrence patterns until approximately two years after surgery (locoregional recurrence: 0.052; distant metastasis: 0.104). Patients with distant metastasis were more likely to die within 5 years of surgery than those with locoregional recurrence (6.8% and 2.6%, respectively).

Conclusions

With the multi-state model, risk factors and post-relapse survival probabilities differed between locoregional recurrence and distant metastasis. These findings may enable clinicians to establish personalized follow-up strategies for patients undergoing curative resection for early stage non-small cell lung cancer.

[Pattern of Recurrence and Metastasis after Radical Resection of Non-small Cell Lung Cancer]

The rate of recurrence and metastasis of non-small cell lung cancer after radical resection is still very high. The risk factors for recurrence and metastasis have been extensively studied, but the dynamic pattern of postoperative recurrence hazard over time is relatively lacking. The dynamic recurrence hazard rate curve is applied to describe the rate of recurrence at any point time among the "at-risk" patients. In this article, by reviewing the previous literature, the characteristics of the dynamic recurrence and metastasis pattern after radical resection of non-small cell lung cancer and the clinical factors affecting the recurrence and metastasis pattern are summarized, in order to screen out specific populations with high recurrence risk and give them personalized follow-up strategy and diagnosis and treatment.
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Different pathologic types of early stage lung adenocarcinoma have different post-operative recurrence patterns

Objectives

To accurately describe the pattern, timing and predictors of disease recurrence after curative resection for different types of early‐stage lung adenocarcinoma (LUAD).

Methods

A total of 1962 patients with early‐stage LUAD were included. The presence of micropapillary, solid components or poorly differentiated cancer as a clinical variable was named “high‐grade” adenocarcinoma (HGADC), while others were classified as “low‐grade” adenocarcinoma (LGADC). Predictive factors for specific recurrence patterns were assessed by univariate and multivariate analyses using Cox‐proportional hazard regression models. Event dynamics, based on the hazard rate, were evaluated.

Results

At a median follow‐up of 36.0 months, 137 (6.98%) of 1962 patients suffered from recurrence. Multivariable Cox analysis revealed that HGADC was an independent predictor for overall recurrence (hazard ratio [HR] 3.08, 95% confidence interval [CI] 2.09–4.52, p < 0.001), local recurrence (HR 2.77, 95% CI 1.38–5.55, p < 0.001), distant metastasis (HR 3.22, 95% CI 2.03–5.11, p < 0.001), chest recurrence (HR 2.80, 95% CI 1.65–4.75, p < 0.001) and brain recurrence (HR 4.11, 95% CI 1.83–9.22, p < 0.001). However, HGADC (HR 1.56, 95% CI 0.63–3.86, p = 0.335 in univariate analysis) was not a risk factor for bone recurrence. The hazard curve of the whole group presented a double‐peaked pattern. Different types of LUAD had different hazard curves. HGADC patients exhibited higher hazard rates than LGADC patients during the whole follow‐up. In addition, the recurrence hazard curve in HGADC patients showed a typical “double‐peaked” pattern, while the curve in LGADC patients displayed a smooth curve after surgery.

Conclusions

Different postoperative recurrence patterns were seen in HGADC and LGADC. Site‐specific recurrence patterns were also different in HGADC and LGADC types.

Annual Hazard Rate of Recurrence in Middle Eastern Papillary Thyroid Cancer over a Long-Term Follow-Up

Predicting the pattern of recurrence in papillary thyroid cancer (PTC) is necessary to establish optimal surveillance and treatment strategies. We analyzed changes in hazard rate (HR) for tumor recurrence over time in 1201 unselected Middle Eastern PTC patients. The changes in risk were further analyzed according to clinical variables predictive of early (≤5 years) and late (>5 years) recurrence using Cox regression analysis to identify patient populations that remain at risk. Tumor recurrence was noted in 18.4% (221/1201) patients. The annualized hazard of PTC recurrence was highest during the first 5 years (2.8%), peaking between 1 and 2 years (3.7%), with a second smaller peak between 13 and 14 years (3.2%). Patients receiving radioactive iodine (RAI) therapy had lower recurrence hazard compared to those who did not (1.5% vs. 2.7%, p = 0.0001). Importantly, this difference was significant even in intermediate-risk PTC patients (0.7% vs. 2.3%; p = 0.0001). Interestingly, patients aged ≥55 years and having lymph node metastasis were at persistent risk for late recurrence. In conclusion, we confirmed the validity of the double-peaked time-varying pattern for recurrence risk in Middle Eastern PTC patients and our findings could help in formulating individualized treatment and surveillance plans.

Time-varying pattern of recurrence risk for localized melanoma in China

BACKGROUND

Acral and mucosal melanomas are rarely seen in Caucasians but common in China. There are limited data on the recurrence characteristics for these patients. This study aimed to identify the recurrence pattern for localized melanoma in China, especially acral and mucosal subtypes.

METHODS

Patients with localized melanoma who underwent radical resection between January 1999 and December 2014 in southern China were retrospectively reviewed. Survival and annual recurrence hazard were analyzed by Kaplan-Meier method and hazard function, respectively.

RESULTS

Totally, 1012 patients were included (acral melanoma 400; chronic sun-induced damage (CSD)/non-CSD melanoma 314; mucosal melanoma 298). Recurrence was recorded in 808 patients (localized 14.1%; regional 29.6%, and distant 56.3%). Mucosal melanoma had local and M1c stage recurrence more frequently than cutaneous melanoma, but less frequent regional node relapse. There was no difference in recurrent site distribution between acral and CSD/non-CSD melanoma. The annual recurrence hazard curve for the entire cohort showed a double-peaked pattern with the first major peak in the second year after surgery and the second peak near the seventh year. Mucosal melanoma had a higher recurrence risk than cutaneous melanoma. Acral melanoma had a lower flat recurrence peak than CSD/non-CSD melanoma. Tumor thickness > 4.0 mm, ulceration, positive regional nodes, and wound infection were associated with a higher recurrence risk in cutaneous melanoma. Adjuvant therapy reduced the recurrence risk of cutaneous melanoma but not of mucosal melanoma.

CONCLUSIONS

This is a large cohort about the rule of recurrence risk in acral and mucosal melanoma and will provide an initial framework for development of surveillance and adjuvant strategy for Chinese melanoma patients.

Time-Varying Pattern of Mortality and Recurrence from Papillary Thyroid Cancer: Lessons from a Long-Term Follow-Up

Background: Little is known about annual hazard rates of cancer mortality and recurrence for papillary thyroid cancer (PTC). This study investigated the time-varying pattern of cancer death and recurrence from PTC and independent prognostic factors for cause-specific mortality (CSM) and recurrence of PTC. Methods: This retrospective chart review enrolled 466 patients diagnosed with PTC who underwent curative initial surgery between April 1981 and December 1991 with a median follow-up of 18.4 years. Clinical characteristics, cancer mortality (primary endpoint), and recurrence (secondary endpoint) were ascertained. The failure rates of either death or recurrence were estimated using the Kaplan-Meier methods, and annual death/recurrence hazard was depicted using hazard function. Results: In this Japanese cohort where only 1.5% of patients received radioactive iodine therapy, the 10-, 20-, and 30-year CSM rates were 2.7%, 6.2%, and 8.6%, respectively. Eleven (44.0%) cases of death occurred within the first 10 years, whereas 10 (40.0%) and 4 (16.0%) cases occurred within 10-20 and 20-30 years after surgery, respectively. The 10-, 20-, and 30-year recurrence rates were 11.3%, 21.8%, and 29.4%, respectively. Forty-six (54.8%) cases of recurrence occurred within the first 10 years, predominantly within the first five years (31 cases; 36.9%), whereas 29 (34.5%), 7 (8.3%), and 2 (2.4%) cases occurred within 10-20, 20-30, and ≥30 years after surgery, respectively. Age ≥55 years was the only independent prognostic factor for CSM. Age ≥55 years, male, tumor size > 4 cm, extranodal extension, and positive pathological lymph node metastasis were independent prognostic factors for recurrence. The annual hazard curve of cancer mortality presented a double-peaked distribution, with a first peak at the 10th year, and the second peak reaching the maximum at the 20th year after surgery for the entire population. The annual hazard curve of recurrence showed a triple-peaked pattern, with surges at about 12, 22, and 29 years after surgery. Conclusions: Patients with PTC harboring at least one of the prognostic characteristics may be at persistent risk of cancer mortality and recurrence even 10 or more years after initial treatment. Understanding the hazard rate of PTC is key to creating more tailored treatment and surveillance.

Evaluation of lobar lymph node metastasis in non-small cell lung carcinoma using modified total lesion glycolysis

Background

Volumetric parameters based on 3-dimensional reconstruction have recently been introduced for cancer staging. We aimed to improve the ability to diagnose hilar lymph node metastasis in patients with non-small cell lung cancer.

Methods

We evaluated 142 patients with non-small cell lung cancer who underwent right upper lobectomy and radical lymph node dissection. Metastatic involvement of right upper lobar lymph nodes was assessed using high-resolution computed tomography (HRCT) and 18F-2-floro-2-deoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT).

Results

On receiver operating characteristic (ROC) curve analysis, the area under the curves (AUC) for short axis, maximum of standardized uptake value (SUV_max), total lesion glycolysis (TLG) and modified TLG (mTLG) were 0.79, 0.77, 0.76, and 0.87, respectively. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of mTLG, using the optimal cut off value (2.45), for diagnosis of lobar lymph node metastasis were 71%, 88%, 44%, and 96%, respectively. Hilar asymmetric uptake (HAU) of FDG was larger in true-positive cases than in false-negative cases (P<0.01). Furthermore, the size of metastatic foci in the lymph node was smaller in false-negative cases (P=0.012).

Conclusions

Modified TLG is a good parameter to diagnose metastatic right upper lobar lymph nodes. Micrometastasis in the lymph node is difficult to predict using the current diagnostic method. However, more careful evaluation is required in patients with symmetric FDG accumulation at hilar region because hilar lymph nodes respond to various causes such as benign pulmonary diseases.

Temporal and regional distribution of initial recurrence site in completely resected N1-stage II lung adenocarcinoma: The effect of postoperative adjuvant chemotherapy

OBJECTIVES

Understanding the timing and pattern of cancer recurrence is essential to explain the causes of treatment failure. We investigated the recurrence pattern and rate over time in patients with completely resected N1-stage II lung adenocarcinoma.

MATERIALS AND METHODS

We retrospectively reviewed the medical records of 333 patients who underwent complete surgical resection for N1-stage II lung adenocarcinoma.

RESULTS

The median recurrence-free survival (RFS) was 38.8 months and the 5-year RFS rate was 39.6%. Left-sided tumors, large tumor size, and lymph node (LN) ratio higher than 0.15 were significantly correlated with a worse RFS, whereas female sex, direct LN involvement, and adjuvant chemotherapy were significantly correlated with a better RFS. Among the 182 patients who experienced recurrences, 46 (25.3%) had only loco-regional recurrences and 136 (74.7%) had distant metastases. The organs most commonly involved in initial recurrence were the lungs (n = 89, 48.9%), followed by bone (n = 41, 22.5%) and the brain (n = 38, 20.9%). The recurrence hazard curve for the entire study population demonstrated a similarly shaped and sized initial and second peak at 15 and 23 months, and a third smaller peak during the fourth year. The recurrence hazard curve of patients who received adjuvant chemotherapy exhibited a more delayed and smaller first peak than those who did not receive adjuvant chemotherapy. The patients treated with adjuvant chemotherapy had a lower rate of distant metastasis (p = 0.037); adjuvant chemotherapy had no effect on brain metastasis (p = 0.640).

CONCLUSION

In the present cohort, the hazard curves suggested that bone and brain recurrences exhibited an earlier first peak, while lung recurrences presented later. Adjuvant chemotherapy not only reduced the recurrence hazard but also delayed the recurrence and altered the pattern of recurrence. However, these results need to be confirmed in a prospective study.

Prognostic significance of ABCB1 in stage I lung adenocarcinoma

Cancer stem cell (CSC) properties have been recently proposed to explain tumor carcinogenesis and multidrug resistance in several human cancers, including non-small cell lung cancer (NSCLC). The present study examined the protein expression of three CSC-associated markers, namely ATP binding cassette subfamily B member 1 (ABCB1), aldehyde dehydrogenase 1 family member A1 (ALDH1A1) and cluster of differentiation (CD) 44, by immunohistochemistry in 194 NSCLC patients who underwent complete resection of NSCLC tumors. The association between the expression of these proteins and patient prognosis was evaluated to clarify the prognostic significance of CSC-associated markers in NSCLC patients. Positive staining for ABCB1 demonstrated a trend toward worse survival compared with negative staining in stage I-III NSCLC. Negative staining for ALDH1 or CD44 exhibited a trend toward worse survival compared with positive staining in stage I-III NSCLC. It was observed that patients with stage I lung adenocarcinoma (ADC) showing positivity for ABCB1 expression had significantly poorer survival than those with negative ABCB1 staining (P=0.03). Furthermore, stage I ADC patients with wild-type epidermal growth factor receptor (EGFR) who exhibited positive staining for ABCB1 had significantly shorter disease-free survival (DFS) compared with patients with negative staining for ABCB1 (P<0.01). Analyses by univariate and multivariate Cox proportional hazards models revealed that ABCB1-positive staining was significantly associated with DFS and was an independent prognostic factor (hazard ratio, 3.49; P<0.05) in these patients. These results suggest that ABCB1 protein expression is useful for predicting prognosis and selecting patients for post-operative therapy in stage I lung ADC patients, particularly those harboring wild-type EGFR.

The dynamic pattern of recurrence in curatively resected non-small cell lung cancer patients: Experiences at a single institution

PURPOSE

To investigate the hazard function of tumor recurrence in patients with completely (R0) resected non-small cell lung cancer.

METHODS

A total of 1374 patients treated between 2003 and 2009 with complete resection and systematic lymph node dissection were studied. The risk of recurrence at a given time after operation was studied utilizing the cause-specific hazard function. Recurrence was categorized as local recurrence or distant recurrence. The risk distribution was assessed using clinical and pathological factors.

RESULTS

The hazard function for recurrence presented an early peak at approximately 10 months after surgery and maintained a tapered plateau-like tail extending up to 8 years. A similar risk pattern was detected for both local recurrence and distant recurrence, while the risk of distant recurrence was higher than that of local recurrence. The double-peaked pattern of hazard rate was present in several subgroups, such as p-stage IA patients. A comparison of histology and status of nodal involvement showed that pN1-2 adenocarcinoma patients demonstrated a high hazard rate of distant recurrence and that pN0 adenocarcinoma patients exhibited a small recurrent risk for a longer time. Squamous cell carcinoma patients showed only little difference in risk.

CONCLUSIONS

The data may be useful to select patients at high risk of recurrence and may provide information for each patient to decide how to manage the postoperative follow-up individually.

Adjuvant Epidermal Growth Factor Receptor Inhibitors in Non-Small Cell Lung Cancer

Nonrandomized studies have suggested a potential benefit with use of an EGFR tyrosine kinase inhibitor in the adjuvant setting in patients with EGFR-mutated non-small cell lung cancer. These nonrandomized studies cannot substitute for well-conducted, adequately powered, prospectively randomized phase III trials. Such trials are under way, and their results are eagerly anticipated.

Progress of Circulating Tumor Cells in Cancer Management

Circulating tumor cells are low-frequency cells that are shed into the peripheral bloodstream from a primary solid tumor and/or metastasis. Although these cells were recognized initially in 1869, it is only in the past 2 decades that they have been isolated for use as a surrogate biomarker to monitor response to therapy, evaluate prognosis, detect tumor mutations, assist in selecting personalized medicine, and enable earlier cancer diagnosis.