Canadian Perspectives: Update on Inhibition of ALK-Positive Tumours in Advanced Non-Small-Cell Lung Cancer

Background: Inhibition of the anaplastic lymphoma kinase (ALK) oncogenic driver in advanced non-small-cell lung carcinoma (NSCLS) improves survival. In 2015, Canadian thoracic oncology specialists published a consensus guideline about the identification and treatment of ALK-positive patients, recommending use of the ALK inhibitor crizotinib in the first line. New scientific literature warrants a consensus update. Methods: Clinical trials of ALK inhibitor were reviewed to assess benefits, risks, and implications relative to current Canadian guidance in patients with ALK-positive NSCLS. Results: Randomized phase III trials have demonstrated clinical benefit for single-agent alectinib and ceritinib used in treatment-naïve patients and as second-line therapy after crizotinib. Phase II trials have demonstrated activity for single-agent brigatinib and lorlatinib in further lines of therapy. Improved responses in brain metastases were observed for all second- and next/third-generation ALK tyrosine kinase inhibitors in patients progressing on crizotinib. Canadian recommendations are therefore revised as follows: (1) Patients with advanced nonsquamous NSCLS have to be tested for the presence of an ALK rearrangement. (2) Treatment-naïve patients with ALK-positive disease should initially be offered single-agent alectinib or ceritinib, or both sequentially. (3) Crizotinib-refractory patients should be treated with single-agent alectinib or ceritinib, or both sequentially. (4) Further treatments could include single-agent brigatinib or lorlatinib, or both sequentially. (5) Patients progressing on ALK tyrosine kinase inhibitors should be considered for pemetrexed-based chemotherapy. (6) Other systemic therapies should be exhausted before immunotherapy is considered. Summary: Multiple lines of ALK inhibition are now recommended for patients with advanced NSCLS with an ALK rearrangement

Crizotinib Inhibition of ROS1-Positive Tumours in Advanced Non-Small-Cell Lung Cancer: A Canadian Perspective

The ROS1 kinase is an oncogenic driver in non-small-cell lung cancer (NSCLC). Fusion events involving the ROS1 gene are found in 1%–2% of NSCLC patients and lead to deregulation of a tyrosine kinase–mediated multi-use intracellular signalling pathway, which then promotes the growth, proliferation, and progression of tumour cells. ROS1 fusion is a distinct molecular subtype of NSCLC, found independently of other recognized driver mutations, and it is predominantly identified in younger patients (<50 years of age), women, never-smokers, and patients with adenocarcinoma histology. Targeted inhibition of the aberrant ROS1 kinase with crizotinib is associated with increased progression-free survival (PFS) and improved quality-of-life measures. As the sole approved treatment for ROS1-rearranged NSCLC, crizotinib has been demonstrated, through a variety of clinical trials and retrospective analyses, to be a safe, effective, well-tolerated, and appropriate treatment for patients having the ROS1 rearrangement. Canadian physicians endorse current guidelines which recommend that all patients with nonsquamous advanced NSCLC, regardless of clinical characteristics, be tested for ROS1 rearrangement. Future integration of multigene testing panels into the standard of care could allow for efficient and cost-effective comprehensive testing of all patients with advanced nsclc. If a ROS1 rearrangement is found, treatment with crizotinib, preferably in the first-line setting, constitutes the standard of care, with other treatment options being investigated, as appropriate, should resistance to crizotinib develop

Renal medullary carcinoma

Renal medullary carcinoma (RMC) is a rare and aggressive form of non-clear cell kidney cancer that typically affects young adults and is almost exclusively associated with sickle cell trait. It has only been recognized in the last two decades and continues to be relatively poorly understood. Patients typically present with pain and hematuria and are often found to have metastatic disease at diagnosis. Prognosis is extremely poor, with a mean survival less than 1 year. Combination chemotherapy has been used with limited success. As we learn more about the genetics of the disease, targeted therapy is being attempted