Utilization of invasive mediastinal nodal staging and prevalence of occult nodal disease in patients with synchronous primary lung cancers.

M01-01: Second primaries

Outcomes After Surgical Management of Synchronous Bilateral Primary Lung Cancers

SUVmax Ratio on PET/CT May Differentiate Between Lung Metastases and Synchronous Multiple Primary Lung Cancer

Synchronous multiple primary lung cancer is rare and difficult to differentiate from metastatic disease. State-of-the-art diagnostic tools may contribute to discern synchronous multiple primary lung cancer from lung cancer or other primary tumors with pulmonary metastases, thus allowing implementation of curative strategies. We report the case of a 72-year-old woman with 3 synchronous primary lung cancers.

Invited Commentary

Molecular profiling of key driver genes improves staging accuracy in multifocal non–small cell lung cancer

Indications for invasive mediastinal staging in patients with early non-small cell lung cancer staged with PET-CT

7575 Background: In patients with NSCLC, preoperative staging tests including mediastinoscopy (M) are important in defining which patients are surgical candidates. 18FDG PET-CT is useful in identifying patients with mediastinal disease not evident by CT. Alternatively, M may not be required if PET-CT is negative. We have previously reported reduced rates of unnecessary thoracotomy (T) in the PET-CT arm of a trial which compared staging with PET-CT versus conventional imaging (bone scan and CT liver and adrenals) in patients with clinical stage I, II, or IIIA NSCLC being considered for surgery (J Clin Oncol 26 May 20 suppl: abstr 7502). Methods: In this analysis, we determined the accuracy of PET-CT in mediastinal staging compared to invasive surgical staging either by M alone or by M and T. Patients in the PET-CT arm had invasive mediastinal staging either by M or mediastinal nodal sampling at T. PET-CT was considered positive if N2 or N3 nodes exhibited increased 18FDG uptake. Results: M was performed in 81 of 143 patients in the PET-CT arm; the remainder had mediastinal nodal staging at T. Combining M with T, the sensitivity and specificity of PET-CT were 0.70 [95% CI: 0.48–0.85] and 0.94 [95%CI: 0.89–0.97], respectively. Of 21 patients with a positive PET-CT, 7 did not have tumor. The positive predictive value (PPV) and negative predictive value (NPV) were 0.67 [95% CI: 0.45–0.83] and 0.95 [95% CI: 0.90–0.98], respectively. The results for PET-CT versus M alone were: sensitivity, 1.0 [95% CI: 0.76–1.0]; specificity, 0.88 [95%CI: 0.79–0.94]; PPV, 0.60 [95%CI: 0.39–0.78]; NPV, 1.0 [95% CI: 0.94–1.0]. Based on PET-CT alone, 7 patients would have been denied T if PET-CT abnormalities had not been evaluated with invasive mediastinal staging. Conclusions: Mediastinal abnormalities on PET-CT should be confirmed by invasive mediastinal staging because of the risk of a false positive test. Patients should not be denied potentially curative therapy based on PET-CT alone. If PET-CT is negative in the mediastinum, the likelihood of occult metastatic disease in the mediastinum is very low and invasive staging may not be required depending on the clinical context. No significant financial relationships to disclose.

Although the number of patients diagnosed with synchronous multiple primary lung cancer is growing because of increased screening and improved imaging technology, synchronous triple primary lung cancer with different histological tumor subtypes occurring in the same lobe of the lung is extremely rare. In this report, we encountered a 64‐year‐old male patient with three different types of nodule in the right lower lobe of the lung found on chest computed tomography (CT) scan. We believed that the patient had triple primary lung cancer, and subsequently performed a right lower lobectomy using video‐assisted thoracoscopic surgery (VATS). The pathological diagnosis was the same as the presurgical diagnosis, but all the nodules were different histological subtypes. To the best of our knowledge, this is the first case reported in the literature of synchronous triple primary lung cancer with three different histological subtypes in the same lobe of the lung.Key pointsSignificant findings of the studyThis is the first case of synchronous triple primary lung cancer with three different histological subtypes in each tumor in the same lobe of the lung.What this study addsWe report the details of the case with immunohistochemical and gene mutation findings, and a literature review of synchronous primary lung cancer.

Metachronous or synchronous primary lung cancer in the era of computed tomography surveillance

BackgroundMultiple primary lung cancer may present in synchronous or metachronous form. Synchronous multiple primary lung cancer is defined as multiple lung lesions that develop at the same time, whereas metachronous multiple primary lung cancer describes multiple lung lesions that develop at different times, typically following treatment of the primary lung cancer. Patients with previously treated lung cancer are at risk for developing metachronous lung cancer, but with the success of computed tomography and positron emission tomography, the ability to detect both synchronous and metachronous lung cancer has increased.Case presentationWe present a case of a 63-year-old Hispanic man who came to our hospital for evaluation of chest pain, dry cough, and weight loss. He had recently been diagnosed with adenocarcinoma in the right upper lobe, with a poorly differentiated carcinoma favoring squamous cell cancer based on bronchoalveolar lavage of the right lower lobe for which treatment was started. Later, bronchoscopy incidentally revealed the patient to have an endobronchial lesion that turned out to be mixed small and large cell neuroendocrine lung cancer. Our patient had triple synchronous primary lung cancers that histologically were variant primary cancers.ConclusionsTriple synchronous primary lung cancer management continues to be a challenge. Our patient’s case suggests that multiple primary lung cancers may still occur at a greater rate than can be detected by high-resolution computed tomography.

Synchronous primary lung cancer (SPLC) occurs in up to 0.5% of patients with lung cancer. Among SPLC cases, coexistence of small cell carcinoma (SCLC) and non-small cell carcinoma has been reported in a very small fraction. Futhermore, there have been no reports discussing treatment and prognosis of SPLC presenting with SCLC and NSCLC. We report on two cases of SPLC presenting SCLC in limited stage and operable NSCLC. One patient developed synchronously SCLC and adenocarcinoma of the lung, while the other SCLC and squamous cell carcinoma of the lung. The clonal origin of these synchronous lung cancers was evaluated using immunohistochemical and polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) analyses. Both of the patients were diagnosed based on transbronchial lung biopsy (TBLB) and mediastinoscopic biopsy. They were successfully treated with chemoradiotherapy and adjuvant surgery, and are now doing well without any signs of tumor progression for about one year. In both cases, a response of mediastinal lymph node for concurrent chemoradiotherapy was quite different from that of the mass in the lung field. In case 2, p53 mutation was observed in the SCLC tissue, but not in the NSCLC tissue by PCR-SSCP. In both cases, carcinoembryonic antigen was documented in the NSCLC tissue, but not in the SCLC tissue by immunohistochemical staining. This report indicates the importance of the accurate diagnosis of SPLC by employing TBLB and/or media-stinoscopy for the optimal treatment of patients having SPLC presenting with SCLC and NSCLC. Diagnostic criteria and standard treatment of this disease should be established.

Introduction In patients with non-small cell lung cancer (NSCLC) who present with multiple pulmonary nodules, it is often difficult to distinguish metastatic disease from synchronous primary lung cancers (SPLC). We sought to evaluate clinical outcomes after stereotactic body radiotherapy (SBRT) alone to synchronous primary lesions. Material and methods Patients with synchronous AJCC 8th Edition Stage IA-IIA NSCLC and treated with stereotactic body radiation therapy (SBRT) to all lesions between 2009–2018 were reviewed. SPLC was defined as patients having received two courses of SBRT within 180 days for treatment of separate early stage tumors. In total, 36 patients with 73 lesions were included. Overall survival (OS), progression-free survival (PFS), cumulative incidence of local failure (LF), and regional/distant failure (R/DF) were estimated and compared with a control cohort of solitary early stage NSCLC patients. Results Median PFS was 38.8 months (95% CI 14.3-not reached [NR]); 3-year PFS rates were 50.6% (35.6–72.1). Median OS was 45.9 months (95% CI: 35.9-NR); 3-year OS was 63.0% (47.4–83.8). Three-year cumulative incidence of LF and R/DF was 6.6% (3.7–13.9) and 35.7% (19.3–52.1), respectively. Patients with SPLC were compared to a control group (n = 272) of patients treated for a solitary early stage NSCLC. There was no statistically significant difference in PFS (p = .91) or OS (p = .43). Evaluation of the patterns of failure showed a trend for worse cumulative incidence of R/DF in SPLC patients as compared to solitary early stage NSCLC (p = .06). Conclusion SBRT alone to multiple lung tumors with SPLC results in comparable PFS, OS, and LF rates to a cohort of patients treated for solitary early stage NSCLC. Those with SPLC had non-significantly higher R/DF. Patients with SPLC should be followed closely for failure and possible salvage therapy.

Invasive mediastinal staging for resected non–small cell lung cancer in a population-based cohort

The Relative Survival Impact of Guideline-Concordant Clinical Staging and Stage-Appropriate Treatment of Potentially Curable Non-Small Cell Lung Cancer