Negative predictive value of positron emission tomography and computed tomography for stage T1-2N0 non-small-cell lung cancer: a meta-analysis

BACKGROUND

Nodal staging of non-small-cell lung cancer (NSCLC) is crucial in evaluation of prognosis and determination of therapeutic strategy. This study aimed to determine the negative predictive value (NPV) of combined positron emission tomography and computed tomography (PET-CT) in patients with stage I (T1-2N0) NSCLC and to investigate the possible risk factors for occult nodal disease.

METHODS

Studies investigating the performance of PET in conjunction with CT in the nodal staging of stage I NSCLC were identified in the MEDLINE database. The initiative of standards for reporting of diagnostic accuracy (STARD) was used to ensure study quality. Pathologic assessments through mediastinoscopy or thoracotomy were required as the reference standard for evaluation of PET-CT accuracy. Stata-based meta-analysis was applied to calculate the individual and pooled NPVs.

RESULTS

Ten studies with a total of 1122 patients with stage I (T1-2N0) NSCLC were eligible for analysis. The NPVs of combined PET and CT for mediastinal metastases were 0.94 in T1 disease and 0.89 in T2 disease. Including both T1 disease and T2 disease, the NPVs were 0.93 for mediastinal metastases and 0.87 for overall nodal metastases. Adenocarcinoma histology type (risk ratio [RR], 2.72) and high fluorine-18 (18F) fluorodeoxyglucose (FDG) uptake in the primary lesion were associated with greater risk of occult nodal metastases.

CONCLUSIONS

Although overall occult nodal metastases in clinical stage T1-2N0 NSCLC is not infrequent, combined PET and CT provide a favorable NPV for mediastinal metastases in T1N0 NSCLC, suggesting a low yield from routine invasive staging procedures for this subgroup of patients.

Poor baseline pulmonary function may not increase the risk of radiation-induced lung toxicity

PURPOSE

Poor pulmonary function (PF) is often considered a contraindication to definitive radiation therapy for lung cancer. This study investigated whether baseline PF was associated with radiation-induced lung toxicity (RILT) in patients with non-small cell lung cancer (NSCLC) receiving conformal radiation therapy (CRT).

METHODS AND MATERIALS

NSCLC patients treated with CRT and tested for PF at baseline were eligible. Baseline predicted values of forced expiratory volume in 1 sec (FEV1), forced vital capacity (FVC), and diffusion capacity of lung for carbon monoxide (DLCO) were analyzed. Additional factors included age, gender, smoking status, Karnofsky performance status, coexisting chronic obstructive pulmonary disease (COPD), tumor location, histology, concurrent chemotherapy, radiation dose, and mean lung dose (MLD) were evaluated for RILT. The primary endpoint was symptomatic RILT (SRILT), including grade ≥2 radiation pneumonitis and fibrosis.

RESULTS

There was a total of 260 patients, and SRILT occurred in 58 (22.3%) of them. Mean FEV1 values for SRILT and non-SRILT patients were 71.7% and 65.9% (P=.077). Under univariate analysis, risk of SRILT increased with MLD (P=.008), the absence of COPD (P=.047), and FEV1 (P=.077). Age (65 split) and MLD were significantly associated with SRILT in multivariate analysis. The addition of FEV1 and age with the MLD-based model slightly improved the predictability of SRILT (area under curve from 0.63-0.70, P=.088).

CONCLUSIONS

Poor baseline PF does not increase the risk of SRILT, and combining FEV1, age, and MLD may improve the predictive ability.

Natural growth and disease progression of non-small cell lung cancer evaluated with 18F-fluorodeoxyglucose PET/CT

PURPOSE

The aims of this study were to: (1) estimate the volumetric and metabolic growth rate of non-small cell lung cancer (NSCLC), (2) evaluate disease progression prior to treatment, and (3) explore the effects of tumor growth rate and time to treatment (TTT) on survival outcome.

METHODS

Patients with inoperable stages I-III NSCLC with serial pre-treatment PET/CT scans were eligible for this study. PET-derived metabolic tumor volumes (PET-MTV) and CT-derived gross tumor volumes (CT-GTV) were contoured using PET/CT information. Normalized standardized uptake values (NSUV) in tumors including the NSUVmean and NSUVmax were measured. Tumor growth rates expressed as doubling time (DT) were estimated using an exponential model. Pre-treatment disease progression defined as the development of any new site of disease on PET/CT and change in TNM stage (AJCC 7th ed.) were recorded. Growth rate and tumor progression were analyzed with respect to overall (OS) and progression free survival (PFS).

RESULTS

Thirty-four patients with a median inter-scan interval (ISI) of 43 days and TTT of 48 days were analyzed. Tumor volumes showed remarkable inter-scan growth while NSUV did not increase significantly. The DT for PET-MTV, CT-GTV, NSUVmean and NSUVmax were 124, 139, 597, and 333 days, respectively. Pre-treatment disease progression occurred in 20.6% patients with longer ISI being a significant risk factor (OR=1.027, p=0.02). The optimal threshold ISI to predict progression was 58 days (4.8% vs. 46.2%, p=0.007). Neither tumor growth rates nor TTT were significantly correlated to OS or PFS.

CONCLUSIONS

NSCLC displays rapid tumor volume growth whereas NSUVmean and NSUVmax are relatively stable over the same time period. Longer delays before initiation of treatment are associated with higher risk of pre-treatment disease progression.

Intensity-Modulated Radiation Therapy May Improve Local-Regional Tumor Control for Locally Advanced Non-Small Cell Lung Cancer Compared With Three-Dimensional Conformal Radiation Therapy

BACKGROUND

Consistent results are lacking as regards the comparative effectiveness of intensity-modulated radiotherapy (IMRT) versus three-dimensional conformal radiotherapy (3DCRT) in patients with locally advanced non-small cell lung cancer (LA-NSCLC).

PATIENTS AND METHODS

Patients treated with definitive radiotherapy (RT) between 2002 and 2010 were retrospectively reviewed. Overall survival (OS), local-regional progression-free survival (LRPFS), distant metastasis-free survival (DMFS), and progression-free survival (PFS) were compared among patients irradiated with different techniques. The association between RT technique and survival indexes was assessed in a Cox proportional hazard regression model. Propensity score matching (PSM) was used to balance known confounding factors.

RESULTS

A total of 652 patients were eligible for analysis, including 206 with 3DCRT and 446 with IMRT. The median OS of the 3DCRT and IMRT groups were 19.4 and 23.3 months, with the 5-year rate of 13% and 19%, respectively (p = .043). Multivariate analysis identified IMRT as an independent favorable factor associated with LRPFS and DMFS. PSM analysis further verified the beneficial effect of IMRT on LRPFS. No difference in OS or PFS was observed between the two techniques. Subgroup analysis revealed that IMRT might be differentially more effective in both OS and LRPFS among patients who were female, nonsmokers, with adenocarcinoma, or without weight loss. There was a significant reduction of lung toxicity and similar esophagus toxicity in the IMRT group when compared with the 3DCRT group.

CONCLUSION

IMRT may confer superior LRPFS and comparable OS than can be achieved with 3DCRT in LA-NSCLC, along with the reduction of pulmonary toxicity.

IMPLICATIONS FOR PRACTICE

Based on the largest number of patients from a single institution, the present study demonstrated that intensity-modulated radiotherapy (IMRT) could provide superior local-regional progression-free survival and similar overall survival compared with the traditional three-dimensional conformal radiotherapy (3DCRT) for stage III non-small cell lung cancer (NSCLC). IMRT was also found to be associated with the significantly decreased incidence of pulmonary toxicity. These results suggest that IMRT should be considered a surrogate for 3DCRT in locally advanced NSCLC and might be the preferred option for a female nonsmoker with adenocarcinoma and a potentially high risk of pulmonary toxicity from radiotherapy.

Increased CYFRA 21-1, CEA and NSE are Prognostic of Poor Outcome for Locally Advanced Squamous Cell Carcinoma in Lung: A Nomogram and Recursive Partitioning Risk Stratification Analysis

OBJECTIVES

This study aimed to: (1) assess the prognostic significance of serum tumor markers in locally advanced squamous cell carcinoma in lung (LA-SCCL); (2) generate a nomogram to predict the overall survival (OS) and (3) identify a prognostic stratification to assist the therapeutic decision-making.

METHODS

LA-SCCL patients receiving definitive radiotherapy and baseline tumor marker measurement were eligible for this retrospective study. Cox proportional hazards regression was used to determine independent factors associated with various survival indexes and a nomogram was created to estimate the 5-year OS probability for individual patient. The identified prognostic factors were recruited into a recursive partitioning analysis (RPA) for OS to stratify patients with distinct outcome.

RESULTS

A total of 224 patients were eligible for analysis. Increased cytokeratin-19 fragment (CYFRA 21-1) was independently associated with inferior OS, progression free survival (PFS) and a borderline decreased local-regional progression free survival (LRPFS). Elevated carcino-embryonic antigen (CEA) served as an unfavorable determinant for OS and increased neuron-specific enolase (NSE) was predictive of poor distant metastasis free survival (DMFS). A nomogram integrating KPS, TNM stage, CEA and CYFRA 21-1 was created, resulting in a c-index of 0.62. RPA identified 4 prognostic classifications, with median OS of 27.6, 19.9, 17.3 and 10.9 months for low, intermediate, high and very-high risk groups, respectively.

CONCLUSIONS

Baseline tumor marker panel including CYFRA 21-1, CEA and NSE can be prognostic of outcome for LA-SCCL receiving definitive radiotherapy. The RPA identified four prognostic subgroups, which could assist personalized therapy and clinical trial design in LA-SCCL.

Radical thoracic radiotherapy may provide favorable outcomes for stage IV non-small cell lung cancer

BACKGROUND

This study investigates the outcome of synchronous stage IV non-small cell lung cancer (NSCLC) patients who received radical thoracic radiotherapy (TRT).

METHODS

We retrospectively reviewed the charts of stage IV NSCLC patients treated with TRT between January 2007 and December 2011. Radiotherapy was considered radical if it was the primary therapy with non-symptom driven intent, or consolidation therapy after initial chemotherapy and the biologically equivalent dose ≥53 Gy halted disease progression. The patients' demographics, disease characteristics, and treatment parameters were uniformly collected.

RESULTS

Eighty-one patients were irradiated with radical intent, including 52% with more than five metastatic lesions. The minimum follow-up was 31.5 months for survivors. The median overall survival (OS) was 20.8 months, with three and four-year OS rates of 23% and 18%, respectively. The median progression-free survival (PFS) was 8.2 months, with one and two-year PFS rates of 23% and 9%, respectively. Partial response (PR) after TRT and administration of targeted therapy were predictive of longer OS. The factors associated with favorable PFS included earlier local tunor node stage, absence of concurrent chemotherapy, and post-TRT PR. No correlation was found between the number of metastatic lesions and survival outcome. Incidences of grade ≥2 toxicities in the lung and esophagus were 9% and 26%, respectively.

CONCLUSIONS

Radical TRT may result in advantageous outcomes for selected stage IV NSCLC patients, regardless of the number of metastatic foci. Patients who achieved post-TRT PR attained the best outcomes.

Lymph node ratio-dependent prognosis stratification and postoperative radiotherapy utilization in T1-2N1 oral cavity carcinoma

OBJECTIVE

Pathological T1-2N1 oral cavity squamous cell carcinoma (pT1-2N1 OCSCC) is a setting with intermediate prognosis whilst without consensus regarding the utilization of postoperative radiotherapy (PORT). This study aimed to investigate the prognostic value of lymph node ratio (LNR) and to further examine its clinical validity for guiding PORT in pT1-2N1 OCSCC.

METHODS

OCSCC patients who received surgery between 2010 and 2015 with at least 6 lymph nodes dissection were extracted from the Surveillance, Epidemiology and End Results (SEER) database. Time-dependent receiver operating characteristic (ROC) analysis was used to identify the optimal cutoff of LNR. Multivariable Cox regression analysis was employed to assess the prognostic value of LNR. Impact of PORT was evaluated in respective subgroups stratified by LNR.

RESULTS

A total of 870 OCSCC patients with pT1-2N1 diseases were eligible for analysis. The 5-year overall survival (OS) and disease-specific survival (DSS) was 57.2% and 67.9% respectively. Time-dependent ROC analyses for OS and DSS concordantly revealed 5.5% as the optimal cutoff of LNR. Significantly higher risks of death (HR = 1.610, 95% CI: 1.139-2.276) and disease-specific death (HR = 1.731, 95% CI: 1.101-2.723) were unveiled in patients with LNR > 5.5%. PORT related improvement on OS (5-year rate: 57.6% vs. 47.3%, p = 0.095) and DSS (5-year rate: 71.0% vs. 53.8%, p = 0.030) was only found in LNR > 5.5% subgroup.

CONCLUSIONS

LNR > 5.5% is indicative of inferior outcome in pT1-2N1 OCSCC, warranting the utilization of PORT in this sub-setting.

Stage-dependent conditional survival and failure hazard of non-metastatic nasopharyngeal carcinoma after intensity-modulated radiation therapy: Clinical implications for treatment strategies and surveillance

Purpose

Conditional survival (CS) and failure hazard estimations can provide important dynamic prognostic information for clinical decision‐making and surveillance counseling. The current study aimed to investigate the CS and dynamic failure hazard in non‐metastatic nasopharyngeal carcinoma (NPC) treated with intensity‐modulated radiotherapy (IMRT).

Methods

Conditional overall survival (COS) and progression‐free survival (CPFS) estimates adjusted for age and gender against each AJCC 8th stage were calculated. Multivariable Cox regression (MCR) models were fitted in the entire population at baseline and subsequently separate MCR models were fitted in patients who have maintained event‐free time of 1 to 10 years to generate respective hazard ratio (HR). Annual hazard rates of death and progression over 10 years for each stage were also estimated.

Results

A total of 1993 patients were eligible for analysis. The estimated 5‐year OS and PFS for entire cohort were 79.0% and 70.7% at initial diagnosis. After 5 years of event‐free follow‐up, additional 5‐year COS and CPFS increased to 85.9% and 85.5%, respectively. Stage I/II maintained dramatically favorable CS and low hazard (< 5%) of death and progression over time. Relative to stage I/II, stage III manifested non‐significantly higher failure hazard for the first 3 years of survivorship and approached to similar level of stage I/II afterwards. Stage IVA presented most impressive improvement in terms of both COS (∆=9.8%) and CPFS (∆ = 16.8%) whereas still drastically inferior to that of stage I‐III across all conditional time points. After 4 years of follow‐up, progression hazard of stage IVA became relatively steady of approximate 6%.

Conclusions

Survival prospect of non‐metastatic NPC improves over years with distinct dynamic patterns across stages, providing important implications for personalized decision‐making in terms of both clinical management and surveillance counseling. Stage‐dependent and hazard‐adapted clinical management and surveillance are warranted.

[Technical advancement improves survival in patients with locally advanced non-small cell lung cancer (LA-NSCLC) receiving definitive radiotherapy]

OBJECTIVE

This study aimed to evaluate the impact of technical advancement of radiation therapy in patients with LA-NSCLC receiving definitive radiotherapy (RT).

METHODS

Patients treated with definitive RT (≥50 Gy) between 2000 and 2010 were retrospectively reviewed. Overall survival (OS), cancer specific survival (CSS), locoregional progression-free survival (LRPFS), distant metastasis-free survival (DMFS) and progression-free survival (PFS) were calculated and compared among patients irradiated with different techniques. Radiation-induced lung injury (RILI) and esophageal injury (RIEI) were assessed according to the National Cancer Institute Common Terminology Criteria for Adverse Events 3.0 (NCI-CTCAE 3.0).

RESULTS

A total of 946 patients were eligible for analysis, including 288 treated with two-dimensional radiotherapy (2D-RT), 209 with three-dimensional conformal radiation therapy (3D-CRT) and 449 with intensity-modulated radiation therapy (IMRT) respectively. The median follow-up time for the whole population was 84.1 months. The median OS of 2D-RT, 3D-CRT and IMRT groups were 15.8, 19.7 and 23.3 months, respectively, with the corresponding 5-year survival rate of 8.7%, 13.0% and 18.8%, respectively (P<0.001). The univariate analysis demonstrated significantly inferior OS, LRPFS, DMFS and PFS of 2D-RT than those provided by 3D-CRT or IMRT. The univariate analysis also revealed that the IMRT group had significantly loger LRPFS and a trend toward better OS and DMFS compared with 3D-CRT. Multivariate analysis showed that TNM stage, RT technique and KPS were independent factors correlated with all survival indexes. Compared with 2D-RT, the utilization of IMRT was associated with significantly improved OS, LRPFS, DMFS as well as PFS. Compared with 3D-CRT, IMRT provided superior DMFS (P=0.035), a trend approaching significance with regard to LRPFS (P=0.073) but no statistically significant improvement on OS, CSS and PFS in multivariate analysis. The incidence rates of RILI were significantly decreased in the IMRT group (29.3% vs. 26.6% vs.14.0%, P<0.001) whereas that of RIET rates were similar (34.7% vs. 29.7% vs. 35.3%, P=0.342) among the three groups.

CONCLUSIONS

Radiation therapy technique is a factor affecting prognosis of LA-NSCLC patients. Advanced radiation therapy technique is associated with improved tumor control and survival, and decreased radiation-induced lung toxicity.

The Current Position of Postoperative Radiotherapy for Salivary Gland Cancer: A Systematic Review and Meta-Analysis

BACKGROUND

Because of the rarity, heterogeneous histology, and diverse anatomical sites of salivary gland cancer (SGC), there are a limited number of clinical studies on its management. This study reports the cumulative evidence of postoperative radiotherapy (PORT) for SGC of the head and neck.

METHODS

A systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched the PubMed, Embase, Cochrane Library, and Web of Science databases between 7th and 10th November 2023.

RESULTS

A total of 2962 patients from 26 studies between 2007 and 2023 were included in this meta-analysis. The median RT dose was 64 Gy (range: 56-66 Gy). The median proportions of high-grade, pathological tumor stage 3 or 4 and pathological lymph node involvement were 42% (0-100%), 40% (0-77%), and 31% (0-75%). The pooled locoregional control rates at 3, 5, and 10 years were 92% (95% confidence interval [CI], 89-94%), 89% (95% CI, 86-93%), and 84% (95% CI, 73-92%), respectively. The pooled disease-free survival (DFS) rates at 3, 5, and 10 years were 77% (95% CI, 70-83%), 67% (95% CI, 60-74%), and 61% (95% CI, 55-67%), respectively. The pooled overall survival rates at 3, 5, and 10 years were 84% (95% CI, 79-88%), 75% (95% CI, 72-79%), and 68% (95% CI, 62-74%), respectively. Severe late toxicity ≥ grade 3 occurred in 7% (95% CI, 3-14%).

CONCLUSION

PORT showed favorable long-term efficacy and safety in SGC, especially for patients with high-grade histology. Considering that DFS continued to decrease, further clinical trials exploring treatment intensification are warranted.