Neoadjuvant erlotinib and surgical resection of a stage iiia papillary adenocarcinoma of the lung with an L861Q activating EGFR mutation

IASLC Multidisciplinary Recommendations for Pathologic Assessment of Lung Cancer Resection Specimens After Neoadjuvant Therapy

Currently, there is no established guidance on how to process and evaluate resected lung cancer specimens after neoadjuvant therapy in the setting of clinical trials and clinical practice. There is also a lack of precise definitions on the degree of pathologic response, including major pathologic response or complete pathologic response. For other cancers such as osteosarcoma and colorectal, breast, and esophageal carcinomas, there have been multiple studies investigating pathologic assessment of the effects of neoadjuvant therapy, including some detailed recommendations on how to handle these specimens. A comprehensive mapping approach to gross and histologic processing of osteosarcomas after induction therapy has been used for over 40 years. The purpose of this article is to outline detailed recommendations on how to process lung cancer resection specimens and to define pathologic response, including major pathologic response or complete pathologic response after neoadjuvant therapy. A standardized approach is recommended to assess the percentages of (1) viable tumor, (2) necrosis, and (3) stroma (including inflammation and fibrosis) with a total adding up to 100%. This is recommended for all systemic therapies, including chemotherapy, chemoradiation, molecular-targeted therapy, immunotherapy, or any future novel therapies yet to be discovered, whether administered alone or in combination. Specific issues may differ for certain therapies such as immunotherapy, but the grossing process should be similar, and the histologic evaluation should contain these basic elements. Standard pathologic response assessment should allow for comparisons between different therapies and correlations with disease-free survival and overall survival in ongoing and future trials. The International Association for the Study of Lung Cancer has an effort to collect such data from existing and future clinical trials. These recommendations are intended as guidance for clinical trials, although it is hoped they can be viewed as suggestion for good clinical practice outside of clinical trials, to improve consistency of pathologic assessment of treatment response.

Clinical Impact of Rare and Compound Mutations of Epidermal Growth Factor Receptor in Patients With Non-Small-Cell Lung Cancer

BACKGROUND

Standard therapy of advanced non-small-cell lung cancer harboring an activating mutation in the epidermal growth factor receptor (EGFR) gene is treatment with tyrosine kinase inhibitors (TKI). However, for rare and compound mutations of the EGFR gene, the clinical evidence of TKI therapy is still unclear.

PATIENTS AND METHODS

A total of 2906 lung cancer samples were analyzed for EGFR mutations during routine analysis between 2010 and 2017. The samples have been investigated by Sanger sequencing and since 2014 by next-generation sequencing.

RESULTS

We detected EGFR mutations in 408 specimens (14%). Among these, we found 41 samples with rare and 22 with compound mutations. In these 63 samples, 56 different rare EGFR mutations occurred. Information about the clinical outcome was available for 37. Among those with rare mutations, only one patient harboring the mutation p.G874D had disease that responded to first-generation TKI therapy. In contrast, the disease of all patients with compound mutations responded to first- or second-generation TKI therapy. Furthermore, we collected data on clinical relevance regarding TKI therapy from different databases and from an additional literature search, and only found data for 36 of the 56 detected rare mutations.

CONCLUSION

Information about the clinical outcome of patients with rare and compound EGFR mutations remains limited. At present, second- and third-generation TKIs are available, which may represent new treatment strategies for these patients. Therefore, it is becoming increasingly important to maintain databases concerning rare EGFR mutations.

Surgical resection of advanced non-small cell lung cancer after a response to EGFR-TKI: presentation of two cases and a literature review

Background

The usefulness of residual tumor resection after epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) treatment remains unclear. We describe two patients who underwent residual tumor resection after responding to EGFR-TKIs for advanced non-small cell lung cancer (NSCLC) harboring EGFR gene mutations, along with a review of the literature.

Case presentation

The patient in Case 1 was a 72-year-old female non-smoker who was initially diagnosed with T2aN2M0, stage IIIA adenocarcinoma harboring an EGFR exon 21 L858R mutation. After 8 months of gefitinib therapy, a marked radiologic response was noted, and right upper lobectomy with systemic lymph node dissection was performed. The patient developed brain metastasis despite continuous gefitinib therapy. The patient in Case 2 was a 68-year-old female non-smoker who was initially diagnosed with T3N2M0, stage IIIA adenocarcinoma and an extensive pulmonary thromboembolism. After 3 months of therapy with afatinib and anticoagulants, a marked radiologic response and symptom relief were achieved. We then performed right bilobectomy with systemic lymph node dissection. She developed bone metastasis despite postoperative afatinib therapy.

Conclusion

The timing and validity of salvage surgery for residual lesions remain unclear when TKIs are offered as first-line therapy to patients with advanced NSCLC. In our two cases, surgery was performed without any complications. Surgical resection of the residual tumor might contribute to good local control. The accumulation of more clinical data is needed to further investigate the role of surgery in patients with advanced NSCLC harboring EGFR gene mutations.

Effects of erlotinib therapy on [(11)C]erlotinib uptake in EGFR mutated, advanced NSCLC

Background

In non-small cell lung cancer (NSCLC) patients off erlotinib therapy, positron emission tomography (PET) using [¹¹C]erlotinib distinguished epidermal growth factor receptor (EGFR) mutations from wild-type EGFR. However, tumor uptake of [¹¹C]erlotinib during erlotinib therapy is unknown. Therefore, the aims of this study were to evaluate tumor [¹¹C]erlotinib uptake in NSCLC patients both on and off erlotinib therapy, to evaluate the effect of erlotinib therapy on tumor perfusion and its correlation to tumor [¹¹C]erlotinib uptake, and also, to investigate simplified uptake parameters using arterial and venous blood samples.

Methods

Ten patients were to be scanned twice with a 1–2-week interval, i.e., on (E+) and off (E−) erlotinib therapy. Each procedure consisted of a low-dose CT scan, a 10-min dynamic [¹⁵O]H₂O PET scan, and a 60-min dynamic [¹¹C]erlotinib PET scan with arterial and venous sampling at six time points. In patients(E+), the optimal compartment model was analyzed using Akaike information criterion. In patients(E−), the uptake parameter was the volume of distribution (V_T), estimated by using metabolite-corrected plasma input curves based on image-derived input functions and discrete arterial and venous blood samples. Tumor blood flow (TBF) was determined by rate constant of influx (K1) of [¹⁵O]H₂O using the 1T2k model and correlated with V_T and K1 values of [¹¹C]erlotinib. The investigated simplified parameters were standardized uptake value (SUV) and tumor-to-blood ratio (TBR) at 40–60 min pi interval.

Results

Of the 13 patients included, ten were scanned twice. In patients(E+), [¹¹C]erlotinib best fitted the 2T4k model with V_T. In all patients, tumor V_T(E+) was lower than V_T(E−) (median V_T(E−) = 1.61, range 0.77–3.01; median V_T(E+) = 1.17, range 0.53–1.74; P = 0.004). Using [¹⁵O]H₂O, five patients were scanned twice. TBF did not change with erlotinib therapy, TBF showed a positive trend towards correlation with [¹¹C]erlotinib K1, but not with V_T. TBR_40–50 and TBR_50–60, using both arterial and venous sampling, correlated with V_T(E−) (all r_s >0.9, P < 0.001), while SUV did not. In patients off and on therapy, venous TBR underestimated arterial TBR by 26 ± 12 and 9 ± 9 %, respectively.

Conclusions

In patients on erlotinib in therapeutic dose, tumor V_T decreases with high variability, independent of tumor perfusion. For simplification of [¹¹C]erlotinib PET scanning protocols, both arterial and venous TBR 40–60 min post injection can be used; however, arterial and venous TBR values should not be interchanged as venous values underestimate arterial values.

Trial registration

Registered at the Netherlands Trial Registry: NTR3670.

Electronic supplementary material

The online version of this article (doi:10.1186/s13550-016-0169-8) contains supplementary material, which is available to authorized users.

Eventual role of EGFR-tyrosine kinase inhibitors in early-stage non-small-cell lung cancer

Nonadvanced non-small-cell lung cancer (NSCLC) has a poor long-term survival from surgery or definitive radiation that is minimally improved with induction/adjuvant conventional chemotherapy. EGFR-tyrosine kinase inhibitors (TKIs), which provide a significant benefit for molecularly selected EGFR-mutant patients with advanced NSCLC, have been infrequently explored in nonadvanced NSCLC to date. Current published studies reported no significant benefit from adding EGFR-TKI to the induction/adjuvant setting. However, many of them present eventual biases such as unpowered statistics, lack of molecular selection, recruitment of low-risk NSCLC, low sample size or unsuitable control arms. Results, strengths and deficiencies of completed and ongoing trials were fully discussed. Similarly, the selection of patients and control arms, the duration and risks of EGFR-TKI therapies in early-stage NSCLC, the evaluation of response and the diagnosis of EGFR status were considered and analyzed.

[Analyzing the Sensitivity of EGFR-L861Q Mutation to TKIs and A Case Report]

背景与目的

对于伴表皮生长因子受体（epidermal growth factor receptor, EGFR）敏感型突变的晚期非小细胞肺癌（non-small cell lung cancer, NSCLC）患者，小分子酪氨酸激酶抑制剂（tyrosine kinase inhibitor, TKI）的显著疗效众所周知。但对于晚期NSCLC伴EGFR-L861Q突变的患者，TKIs治疗是否敏感，治疗时机和治疗方案该如何选择，至今尚无确切的循证医学证据。本研究旨在通过分析EGFR-L861Q与敏感突变型EGFR-L858R及野生型EGFR蛋白质空间构象的差异，结合临床实例探讨晚期NSCLC伴EGFR-L861Q突变患者的最佳治疗方案。

方法

利用同源模建重建野生型EGFR、敏感突变型EGFR-L858R及突变型EGFR-L861Q蛋白质的空间构象，并分析这三种空间构象之间的差异。

结果

敏感突变型EGFR-L858R与野生型EGFR蛋白质的空间构象差异显著。突变型EGFR-L861Q与敏感突变型EGFR-L858R及野生型EGFR的蛋白质空间构象均不完全相同。在临床中，我们总结了1例晚期NSCLC伴EGFR-L861Q突变的患者，应用化疗作为一线治疗，当肿瘤不再缩小时，换用TKIs维持治疗，复查肺部计算机断层扫描（computed tomography, CT），肿瘤较前相比进一步缩小。

结论

通过对突变型EGFR-L861Q的蛋白质空间构象进行分析比对，结合临床实例，对于晚期NSCLC伴EGFR-L861Q突变的患者，一线化疗后达到疾病控制时，换用TKIs维持治疗，可能获得令人满意的临床疗效。

Effectiveness of gefitinib against non-small-cell lung cancer with the uncommon EGFR mutations G719X and L861Q

Introduction:

In non–small-cell lung cancer, an exon 19 deletion and an L858R point mutation in the epidermal growth factor receptor (EGFR) are predictors of a response to EGFR-tyrosine kinase inhibitors. However, it is uncertain whether other uncommon EGFR mutations are associated with sensitivity to EGFR-tyrosine kinase inhibitors.

Methods:

A post-hoc analysis to assess prognostic factors was performed with the use of patients with EGFR mutations (exon 19 deletion, L858R, G719X, and L861Q) who were treated with gefitinib in the NEJ002 study, which compared gefitinib with carboplatin-paclitaxel as the first-line therapy.

Results:

In the NEJ002 study, 225 patients with EGFR mutations received gefitinib at any treatment line. The Cox proportional hazards model indicated that performance status, response to chemotherapy, response to gefitinib, and mutation types were significant prognostic factors. Overall survival (OS) was significantly shorter among patients with uncommon EGFR mutations (G719X or L861Q) compared with OS of those with common EGFR mutations (12 versus 28.4 months; p = 0.002). In the gefitinib group (n = 114), patients with uncommon EGFR mutations had a significantly shorter OS (11.9 versus 29.3 months; p < 0.001). By contrast, OS was similar between patients with uncommon mutations and those with common mutations in the carboplatin-paclitaxel group (n = 111; 22.8 versus 28 months; p = 0.358).

Conclusions:

The post-hoc analyses clearly demonstrated shorter survival for gefitinib-treated patients with uncommon EGFR mutations compared with the survival of those with common mutations and suggest that the first-line chemotherapy may be relatively effective for non–small-cell lung cancer with uncommon EGFR mutations.

Use of a tyrosine kinase inhibitor as neoadjuvant therapy for non-small cell lung cancer: A case report

We report here a 66-year-old woman diagnosed with bronchioloalveolar carcinoma of the right lung cT4N2M0. The patient was from the Philippines, had never smoked, and tested positive for an EGFR mutation. She received gefitinib as neoadjuvant therapy for two months and displayed a partial response. The tumour was resected by performing a right pneumonectomy. The residual viable tumour accounted for less than 10%. Adjuvant chemotherapy with carboplatin-taxol was administered for four cycles. Fifteen months post-surgery, two brain metastases were found. Gefitinib was prescribed, and one month later complete radiological response was assessed. The patient remains asymptomatic and without visible disease four months later. Controlled randomised trials are needed to clarify the role of these target therapies in the neoadjuvant setting.