Uterine metastasis of lung adenocarcinoma under molecular target therapy with epidermal growth factor receptor tyrosine kinase inhibitors: A case report and review of the literature

Next-generation sequencing assisted diagnosis of cervical metastasis in EGFR-mutated lung adenocarcinoma: A case report

EGFR mutation has been detected in more than half of non-small cell lung cancer (NSCLC) patients in Asia. Lung cancer is the main cause of malignant tumor-related death worldwide. Although distant metastases often occurs in patients with advanced NSCLC, uterine cervical metastasis is rare. Here, we report a case of EGFR-mutated lung adenocarcinoma with cervical metastasis. A 63-year-old female with known lung adenocarcinoma was found to have abnormal vaginal bleeding during osimertinib follow-up visits. Immunohistochemical (IHC) staining and next-generation sequencing (NGS) of the biopsy sample from the uterine cervical tumor confirmed metastatic dissemination from the primary lung malignancy. NGS assisted the diagnosis of uterine cervical metastasis from the primary lung. This is another major clinical application of NGS in addition to medication guidance and identification of drug resistance mechanisms.

Response to lorlatinib on a patient with ALK-rearranged non-small cell lung cancer harboring 1151Tins mutation with uterine metastasis

We describe a case of an anaplastic lymphoma kinase (ALK)‐rearranged non‐small cell lung cancer with development of uterine metastasis after crizotinib and alectinib treatment. Gene analysis from the tissue of uterine metastasis revealed the presence of 1151Tins, which was considered to be a crizotinib and alectinib resistance mutation. Subsequent therapy with the third‐generation ALK inhibitor lorlatinib, but not ceritinib, showed antitumor activity for 1 year. The uterus is an uncommon site for metastasis from lung cancer, and our case indicated that serial gene analysis could provide new information about ALK inhibitor resistance.

Modulating the function of ABCB1: in vitro and in vivo characterization of sitravatinib, a tyrosine kinase inhibitor

BACKGROUND

Overexpression of ATP-binding cassette (ABC) transporter is a major contributor to multidrug resistance (MDR), in which cancer cells acquire resistance to a wide spectrum of chemotherapeutic drugs. In this work, we evaluated the sensitizing effect of sitravatinib, a broad-spectrum tyrosine kinase inhibitor (TKI), on ATP-binding cassette subfamily B member 1 (ABCB1)- and ATP-binding cassette subfamily C member 10 (ABCC10)-mediated MDR.

METHODS

MTT assay was conducted to examine cytotoxicity and evaluate the sensitizing effect of sitravatinib at non-toxic concentrations. Tritium-labeled paclitaxel transportation, Western blotting, immunofluorescence analysis, and ATPase assay were carried out to elucidate the mechanism of sitravatinib-induced chemosensitization. The in vitro findings were translated into preclinical evaluation with the establishment of xenograft models.

RESULTS

Sitravatinib considerably reversed MDR mediated by ABCB1 and partially antagonized ABCC10-mediated MDR. Our in silico docking simulation analysis indicated that sitravatinib strongly and stably bound to the transmembrane domain of ABCB1 human-mouse chimeric model. Furthermore, sitravatinib inhibited hydrolysis of ATP and synchronously decreased the efflux function of ABCB1. Thus, sitravatinib could considerably enhance the intracellular concentration of anticancer drugs. Interestingly, no significant alterations of both expression level and localization of ABCB1 were observed. More importantly, sitravatinib could remarkably restore the antitumor activity of vincristine in ABCB1-mediated xenograft model without observable toxic effect.

CONCLUSIONS

The findings in this study suggest that the combination of sitrvatinib and substrate antineoplastic drugs of ABCB1 could attenuate the MDR mediated by the overexpression of ABCB1.

Isolated uterine metastasis from a lung adenocarcinoma

A 65-year-old woman was referred with an incidental finding of a flurodeoxyglucose-avid uterine lesion, following excision of a local lung adenocarcinoma. MRI had features concerning for an atypical fibroid or smooth muscle tumour of uncertain malignant potential. She underwent a total abdominal hysterectomy and bilateral salpingo-oophorectomy. Histopathology demonstrated a leiomyoma infiltrated with adenocarcinoma consistent with a secondary lesion from the lung cancer. Among the small number of cases of uterine metastases of extra-pelvic primary cancers reported in the literature, those from lung cancers are very rare. Concerning features for an atypical fibroid included the patient's age and postmenopausal status, as well as positron emission tomography and MRI findings. A metastatic secondary cancer was not suspected. Diagnosis was only made after histopathological examination. This case represents a very unusual cause of a uterine mass. It demonstrates the importance of thorough preoperative work-up and accurate histopathological assessment.