Should Epidermal Growth Factor Receptor-Tyrosine Kinase Inhibitor Be Continued beyond Progressive Disease?

Osimertinib and chemotherapy combination to treat brain metastasis flare and osimertinib resistance by EGFR C797S

Chemotherapy or involvement in a clinical trial remain the standard treatment for patients with EGFR mutant non-small cell lung cancer who have disease progression while receiving Osimertinib. Rapid progression, also known as flare-phenomenon, has been described after discontinuation of tyrosine kinase inhibitors. In this case, we describe a young woman who has extracranial progressive disease due to EGFR C797S resistance mutation while being treated with osimertinib, with a rapid neurological deterioration after osimertinib withdrawal due to flare-phenomenon progression in the brain, and a prompt intracranial response with osimertinib reintroduction in addition to chemotherapy to achieve extracranial diseases control.

Intimal Sarcoma of the Pulmonary Artery Treated with Pazopanib

Intimal sarcoma is a rare disease with a poor prognosis. We herein report the case of a 71-year-old man with intimal sarcoma of the pulmonary artery treated with pazopanib. The tumor showed regression after 1 month of treatment. Hand-foot syndrome led to cessation of pazopanib, which triggered a disease flare. Pazopanib should be considered in patients with intimal sarcoma of the pulmonary artery that is unresectable or recurrent after surgery or cytotoxic chemotherapy. We must be careful about drug cessation, as it can lead to a disease flare.

Tyrosine kinase inhibitors re-treatment beyond progression: choice and challenge

Tyrosine kinase inhibitors (TKIs) are highly effective agents for the treatment of lung cancer which harbors activated gene mutation. However, for patients with failure of TKI, TKI re-treatment beyond progression (TRBP) is still a potential option that has been proven by many literatures. In this review, we summarize the clinical evidence of TRBP and discuss the potential mechanisms to overcome TKI-acquired resistance.

Disease flare after discontinuation of crizotinib in anaplastic lymphoma kinase-positive lung cancer

We report the case of a 50-year-old male former smoker. He was diagnosed as having lung adenocarcinoma and treated with induction chemoradiation therapy followed by surgery and adjuvant chemotherapy. Molecular testing revealed that his tumor had an echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase (EML4-ALK) rearrangement. Therefore, he was treated with crizotinib when his disease recurred. He achieved a partial response, which persisted for 10 months until progressive disease was confirmed. Crizotinib was continued for 1 month and the tumor size increased slightly. At that time, crizotinib was discontinued and he participated in a clinical trial of erlotinib ± Met inhibitor; however, his disease progressed rapidly after discontinuation of crizotinib, and the diagnosis of disease flare was made. Readministration of crizotinib was started immediately; however, his disease progressed rapidly, and he died 2 days after starting crizotinib retreatment. Currently, the incidence of disease flare is unknown and it is impossible to predict who will experience it. Therefore, continuing crizotinib after disease progression may be a reasonable option to avoid disease flare.

Successful treatment with erlotinib of severe neutropenia induced by gefitinib in a patient with advanced non-small cell lung cancer

Neutropenia is a rare side effect of gefitinib and was scarcely reported in many large-scale randomized phase III trials using gefitinib monotherapy as first-line treatment. A 77-year-old female was referred to our institution due to abnormal shadow of the right lung, diagnosed by CT scan and biopsy histopathology as adenocarcinoma of the lung (cT3N1M1b). Mutation analysis with PCR-Invader assay of tumor DNA samples revealed short in-frame deletion in exon 19. Based on the diagnosis, first-line treatment was initiated using oral gefitinib (250 mg, daily). During the initial 27 days of gefitinib therapy, the only side effect was a mild skin rash. After 28 days, there was marked tumor shrinkage, indicative of a partial response to gefitinib; however, grade 4 neutropenia was also detected. The patient was switched to the oral erlotinib monotherapy (150 mg/day) as second-line chemotherapy with careful monitoring of neutropenia. Discontinuation of the gefitinib, without the need for granulocyte colony-stimulating factor support, was successful in allowing the neutrophils and leukocytes counts to recover to normal by day 47. The patient continued oral erlotinib for more than 9 months and there has been no evidence of neutropenia, leukopenia, or disease progression. Clinicians should be aware that gefitinib-induced neutropenia in patients with non-small cell lung cancer can be treated successful by switching to erlotinib.