Successful treatment of refractory lung adenocarcinoma harboring a germline BRCA2 mutation with olaparib: A case report

Metastatic lung adenocarcinoma with BRCA2 mutation and longstanding disease control on olaparib, developing triple negative breast adenocarcinoma with additional BRCA2 reversion mutation: a case report

BACKGROUND

The BRCA2 gene is a well-known tumor suppressor gene implicated in breast and ovarian cancers. BRCA1/2 mutations can be sensitive to poly ADP-ribose polymerase (PARP) inhibitors such as olaparib. However, some of these patients develop resistance to this treatment and an essential factor contributing to acquired insensitivity is the occurrence of reversion mutations in the BRCA1/2 genes.

CASE PRESENTATION

We report the case of a 65-year-old Brazilian female patient who had previously been diagnosed with metastatic lung carcinoma carrying a BRCA2 mutation that had extended to the central nervous system. Following disease progression, olaparib was administered, resulting in a stabilizing effect on her condition for ~ 30 months. During a routine follow-up, a new triple-negative breast tumor was found. Genetic testing revealed the presence of two distinct BRCA2 gene mutations in the breast tumor. The original mutation (p.Val220Ilefs4) led to a frameshift, culminating in the production of a truncated and non-functional BRCA2 protein; the second mutation, K437fs22, rectified the reading frame of exon 11. Consequently, Rad51 could properly bind to BRCA2-an essential protein crucial for DNA repair. This restoration resulted in a functional BRCA2 protein, effectively elucidating the clinical resistance observed in the new breast tumor in this case.

CONCLUSIONS

This case report highlights the clinical significance of comprehensive next-generation sequencing analyses for lung adenocarcinomas, both at diagnosis and upon progression. Such analyses enable informed decisions regarding targeted therapies and facilitate a deeper comprehension of resistance mechanisms.

BRCA2 mutation in advanced lung squamous cell carcinoma treated with Olaparib and a PD-1 inhibitor: a case report

Background

Mutations in the human breast cancer susceptibility gene 2 (breast cancer 2, BRCA2) increase the risk of breast, ovarian and other cancers. Olaparib, an oral poly[adenosine diphosphate (ADP)-ribose] polymerase (PARP) inhibitor, is usually prescribed to treat BRCA mutated tumors, especially breast and ovarian cancers. Programmed cell death-1 (PD-1) inhibitors have revolutionized the treatment of lung cancer and many other cancers by destroying the interaction between receptors with ligands in the tumor-immune microenvironment and enabling T cells to recognize and attack cancer cells.

Case description

In our study, we report a patient with advanced BRCA2 lung squamous cell carcinoma who received platinum-based chemotherapy combined with paclitaxel. Seven months later, the disease progressed. BRCA2 mutations were detected in peripheral blood by next-generation sequencing. After 2 months of treatment with Olaparib combined with Cindilimab, the patient was in partial remission and the progression-free survival (PFS) lasted for 6 months, but the patient developed immune renal damage.

Conclusions

This study adds to the clinical data for the treatment of BRCA2 mutant non-small cell lung cancer by demonstrating that lung squamous cell carcinoma has a good response to PARP inhibitors. It also serves as a reminder that there may still be some negative effects from targeted superimposed immunotherapy.

Combined PARP inhibitors and small molecular inhibitors in solid tumor treatment (Review)

With the development of precision medicine, targeted therapy has attracted extensive attention. Poly(ADP‑ribose) polymerase inhibitors (PARPi) are critical clinical drugs designed to induce cell death and are major antitumor targeted agents. However, preclinical and clinical data have revealed the limitations of PARPi monotherapy. Therefore, their combination with other targeted drugs has become a research hotspot in tumor treatment. Recent studies have demonstrated the critical role of small molecular inhibitors in multiple haematological cancers and solid tumors via cellular signalling modulation, exhibiting potential as a combined pharmacotherapy. In the present review, studies focused on small molecular inhibitors targeting the homologous recombination pathway were summarized and clinical trials evaluating the safety and efficacy of combined treatment were discussed.

Case report: olaparib use in metastatic lung adenocarcinoma with BRCA2 pathogenic variant

Poly (ADP-ribose) polymerase (PARP) inhibitors have been approved in malignancies associated with germline BRCA1 or BRCA2 pathogenic variants, such as breast, ovarian, prostate, and pancreatic cancer. In malignancies not associated with germline BRCA1 or BRCA2 pathogenic variants, the therapeutic relevance of PARP inhibitors is less clear. Non-small-cell lung cancer (NSCLC) is known to demonstrate somatic alterations in BRCA1 or BRCA2 gene. The current report is on a gentleman with metastatic lung adenocarcinoma with a somatic BRCA2 pathogenic variant, who was effectively treated with olaparib. Furthermore, we discuss the existing data for use of PARP inhibitors in NSCLC. This study highlights the utility of next-generation sequencing in identifying gene mutations and demonstrates how such information can be used to select targeted therapies in patients with actionable molecular alterations.

Rapid and durable response to fifth-line lorlatinib plus olaparib in an ALK -rearranged, BRCA2-mutated metastatic lung adenocarcinoma patient with critical tracheal stenosis: a case report

Treatment options for heavily treated anaplastic lymphona kinase (ALK )-positive nonsmall cell lung cancer (NSCLC) patients, who typically bear-resistant mechanisms to ALK tyrosine kinase inhibitors (TKIs), are usually limited to chemotherapy, which elicits limited clinical benefit and may incur severe toxicity. It is clinically relevant to explore other revenues for these patients. poly (ADP-ribose) polymerase (PARP) inhibitors, such as olaparib are currently approved to treat BReast CAncer gene 1/2 ( BRCA1/2 )-mutated patients in a few tumor types. There have been a trial and two case reports of an olaparib-containing regimen in treating epidermal growth factor receptor (EGFR)-positive or driver-negative NSCLC. We report a case of a 27-year-old female nonsmoker diagnosed with ALK -rearranged metastatic lung adenocarcinoma. She was treated with alectinib and acquired ALK p.I1171N and p.V1180L mutations. Germline BRCA2 p.F2801fs was also identified. After sequential lines of ceritinib and chemotherapy, lorlatinib was chosen as the fourth-line therapy and maintained control for 6 months. Shortly after progression, the patient was admitted to the ICU due to critically severe stenosis caused by a tracheal mass and soon relieved by embolization and stenting. Afterward lorlatinib plus olaparib was started and elicited a rapid response within 1 month. The progression-free survival was 6 months as of the latest follow-up, with the best response of partial response. To the best of our knowledge, this case is the first to provide clinical evidence of antitumor activity of olaparib plus ALK TKI in ALK -positive, g BRCA -mutated metastatic NSCLC. Together with previous reports in EGFR -positive or driver-negative patients, our finding warrants further studies on PARP inhibition in BRCA1/2 -mutated NSCLC.