Early-Stage Primary Lung Neuroendocrine Tumors Treated With Stereotactic Body Radiation Therapy: A Multi-Institution Experience.

PURPOSE: Current guidelines recommend surgery as standard of care for primary lung neuroendocrine tumor (LNET). Given that LNET is a rare clinical entity, there is a lack of literature regarding treatment of LNET with stereotactic body radiation therapy (SBRT). We hypothesized that SBRT could lead to effective locoregional tumor control and long-term outcomes. METHODS AND MATERIALS: We retrospectively reviewed 48 tumors in 46 patients from 11 institutions with a histologically confirmed diagnosis of LNET, treated with primary radiation therapy. Data were collected for patients treated nonoperatively with primary radiation therapy between 2006 and 2020. Patient records were reviewed for lesion characteristics and clinical risk factors. Kaplan-Meier analysis, log-rank tests, and Cox multivariate models were used to compare outcomes. RESULTS: Median age at treatment was 71 years and mean tumor size was 2 cm. Thirty-two lesions were typical carcinoid histology, 7 were atypical, and 9 were indeterminate. The most common SBRT fractionation schedule was 50 to 60 Gy in 5 daily fractions. Overall survival at 3, 6, and 9 years was 64%, 43%, and 26%, respectively. Progression-free survival at 3, 6, and 9 years was 88%, 78%, and 78%, respectively. Local control at 3, 6, and 9 years was 97%, 91%, and 91%, respectively. There was 1 regional recurrence in a paraesophageal lymph node. No grade 3 or higher toxicity was identified. CONCLUSIONS: This is the largest series evaluating outcomes in patients with LNET treated with SBRT. This treatment is well tolerated, provides excellent locoregional control, and should be offered as an alternative to surgical resection for patients with early-stage LNET, particularly those who may not be ideal surgical candidates.

Programmed death-ligand 1 (PD-L1) expression predicts response to neoadjuvant chemotherapy in triple-negative breast cancer: a systematic review and meta-analysis.

BACKGROUND: In patients with metastatic triple-negative breast cancer (TNBC), programmed death-ligand 1 (PD-L1) expression has been demonstrated to predict response to immunotherapy. It is unclear whether PD-L1 expression measured with currently available validated assays can predict chemotherapy response in patients with non-metastatic TNBC. METHODS: We conducted a systematic review and meta-analysis of clinical studies to assess the PD-L1 expression as a predictor of response to chemotherapy in non-metastatic TNBC using validated assays. The primary endpoint was pathological complete response (pCR) rate to neoadjuvant chemotherapy. Secondary endpoints included the prevalence of PD-L1 expression in non-metastatic TNBC and its impact on disease-free survival (DFS) and overall survival (OS). Moreover, RNA sequence data from the TCGA breast cancer cohort was used to define the relationship between PDCD1 expression and response to chemotherapy and prognosis. RESULTS: Nineteen studies were eligible for the meta-analysis with a total of 2403 patients with non-metastatic TNBC disease. The PD-L1-positive cohort had a significantly higher likelihood of achieving pCR with neoadjuvant chemotherapy (pooled odds ratio = 1.95; 95% CI = 1.39-2.73, p < 0.0001). In studies which reported long-term outcomes, PD-L1 positivity was associated with significantly better DFS and OS compared to PD-L1 negative patients (pooled hazard ratio = 0.51; 95% CI = 0.35-0.74, p < 0.0001 and 0.51; 95% CI = 0.27-0.94, p = 0.031, respectively). Transcriptomic data suggested that PD-L1 expression is a surrogate marker for the upregulation of key immune-related genes that mediate response to chemotherapy in TNBC. CONCLUSION: This analysis clearly shows that patients with PD-L1 positive TNBC respond better to neoadjuvant chemotherapy and are associated with better survival outcomes compared to patients with PD-L1 negative tumours. The newly distinct quadruple negative breast cancer (QNBC) subtype should be defined as the BC subtype with the poorest outcome in the non-metastatic setting, highlighting the need for more aggressive therapy approaches.

Pathological responses and survival outcomes in patients with locally advanced breast cancer after neoadjuvant chemotherapy: a single-institute experience.

BACKGROUND: Pathological complete response (pCR) is a surrogate for the efficacy of neoadjuvant chemotherapy (NCT) in locally advanced breast cancer (LABC). We analyzed the predictive clinical factors for pathological responses and survival outcomes in a cohort of Egyptian patients. METHODS: We evaluated the medical records of patients with breast cancer who received NCT in our academic institute. Survival curves were estimated with the Kaplan-Meier method. Cox proportional models were used for multiple regression analysis. RESULTS: Our cohort included 368 patients with a median age of 48 years (range 21-70). The median follow-up time was 3 years. The clinical tumor stage (T3-4) represented 58%, with 80% having positive axillary nodes. The luminal subgroup prevailed by 68%. The objective response rate (ORR) reached 78%, and 16% of patients achieved pCR. The clinical node stage and optimal chemotherapy were associated with higher ORR (p = 0.035 and p = 0.001, respectively). Predictors of pCR were clinical T-stage (p = 0.026), high Ki-67 index > 20 (p = 0.05), and receiving optimal chemotherapy (p = 0.014). The estimated 3-year disease free-survival (DFS) was 53%. Receptor status, achieving ORR, and pCR were associated with better DFS with hazard ratios of 0.56, p = 0.008; 0.38, p = 0.04; and 0.28, p = 0.007, respectively. CONCLUSIONS: Luminal tumors still draw benefit from neoadjuvant chemotherapy in terms of clinical response and breast conservative surgery. Treatment escalation to those who did not achieve pCR requires more investigation, given a higher recurrence rate in real-world experience.

Combining radiation therapy and immunotherapy for lung cancers: a narrative review.

Lung cancer remains the leading cause of cancer morbidity and mortality worldwide among both men and women. While surgical resection remains the standard of care for early stage NSCLC, chemoradiation has been a mainstay of treatment for locally advanced non-small-cell lung cancer (LA-NSCLC) patients for decades. Consolidation immunotherapy has improved survival in this subset of patients after conventional chemoradiation, and has emerged as the new standard. The synergy between immunotherapy and radiation, as well as ongoing research on the effects of radiation on the immune system, allows for the exploration of new avenues in the treatment of LA-NSCLC. In addition to the use of durvalumab as consolidative systemic therapy after concurrent chemoradiotherapy for Stage III NSCLC, other combination regimens have been shown to be effective in various disease stages in preclinical and clinical studies. These regimens include CTLA-4 and PD/PDL-1 checkpoint inhibitors combined with radiation treatment. While these combined regimens have demonstrated efficacy, they are not without toxicity, and require additional evaluation when combined with radiation. In this review, we have summarized the immunostimulatory and immunosuppressive effects of radiation therapy. We also evaluate the current evidence and ongoing research supporting the combination of radiotherapy and immunotherapy across early to LA-NSCLC.