Gastrointestinal tract metastasis of lung cancer: The PD-L1 expression and correlated clinicopathological variables

The analysis about the metastases to Gastrointestinal tract: a literature review, 2000-2023

Background

Cancers of the gastrointestinal tract exhibit a high detection rate, ranking as the fifth most common malignant tumor and the fourth leading cause of cancer-related death. In addition to primary malignant tumors of the gastrointestinal tract, secondary metastatic tumors significantly impact patient survival. The differentiation between primary and secondary gastrointestinal tumors remains a critical issue requiring further research and analysis.

Methods

This is a retrospective, observational study conducted from 2000 to 2023. We systematically searched the literature in PubMed, EMBASE, and COCHRANE databases from January 1, 2000, to November 31, 2023. Patients diagnosed with gastrointestinal (GI) tract metastasis were included in the study.

Results

A total of 165 patients were enrolled in this study. The most prevalent primary tumors were breast cancer (50.30%), renal cancer (16.96%), lung cancer (16.36%), melanoma (12.72%), and liver cancer (3.63%). The median interval between the diagnosis of the primary tumor and the detection of GI metastatic lesions was 8.53 years (range: 1-25 years). The most frequent endoscopic finding was a solitary mucosal or submucosal lesion situated in the gastric body. Metastases to extra-gastrointestinal organs were observed in the majority of patients. The integration of endoscopic biopsy with pathological and immunohistochemical analyses is essential for identifying the tumor origin. Surgical intervention in patients lacking extra-gastrointestinal metastases may improve prognosis.

Conclusions

Breast, renal, lung, liver cancer, and melanoma were identified as the most frequent primary tumors. Clinical symptoms and endoscopic features were unable to predict the primary sites, which still require immunohistochemical analysis for accurate identification. The intervention modality and the presence or absence of distant metastasis significantly influenced patient prognosis.

The current status and future of PD-L1 in liver cancer

The application of immunotherapy in tumor, especially immune checkpoint inhibitors (ICIs), has played an important role in the treatment of advanced unresectable liver cancer. However, the efficacy of ICIs varies greatly among different patients, which has aroused people's attention to the regulatory mechanism of programmed death ligand-1 (PD-L1) in the immune escape of liver cancer. PD-L1 is regulated by multiple levels and signaling pathways in hepatocellular carcinoma (HCC), including gene variation, epigenetic inheritance, transcriptional regulation, post-transcriptional regulation, and post-translational modification. More studies have also found that the high expression of PD-L1 may be the main factor affecting the immunotherapy of liver cancer. However, what is the difference of PD-L1 expressed by different types of cells in the microenvironment of HCC, and which type of cells expressed PD-L1 determines the effect of tumor immunotherapy remains unclear. Therefore, clarifying the regulatory mechanism of PD-L1 in liver cancer can provide more basis for liver cancer immunotherapy and combined immune treatment strategy. In addition to its well-known role in immune regulation, PD-L1 also plays a role in regulating cancer cell proliferation and promoting drug resistance of tumor cells, which will be reviewed in this paper. In addition, we also summarized the natural products and drugs that regulated the expression of PD-L1 in HCC.

Gastrointestinal bleeding due to jejunal metastasis of pleomorphic lung carcinoma: a case report

Gastrointestinal metastasis of pleomorphic lung cancer presents with nonspecific manifestations, leading to delayed diagnosis. Herein, the authors report the case of a 56-year-old patient who presented with gastrointestinal bleeding due to pleomorphic lung carcinoma.

Case presentation

A 56-year-old patient presented to the emergency department with melena. On examination, he was hemodynamically stable. He had a sensitive and mobile mass in the periumbilical region. A thoracoabdominal computed tomography scan showed a mass of the right apical superior lobe measuring 4 cm and a lobulated jejunal mass measuring 10 cm. A percutaneous biopsy of the lung tumor revealed primary pleomorphic lung carcinoma. The authors performed a midline laparotomy and made a bowel resection with an end-to-end anastomosis. The postoperative course was marked by severe nosocomial pneumonia, leading to septic shock and death. The histopathologic examination concluded with a metastatic lesion of pleomorphic lung carcinoma.

Clinical discussion

The authors reported a rare case of jejunal metastasis of pleomorphic lung cancer. Pleomorphic carcinoma of the lung is a rare pathology that accounts for 0.1-0.4% of nonsmall-cell lung cancer. The prognosis is poor. In the presence of gastrointestinal bleeding caused by small bowel metastases of pleomorphic lung cancer, surgery is the treatment of choice.

Conclusions

Small bowel metastasis of pleomorphic lung cancer is rare. Surgical treatment is the treatment of choice. The authors highlight the importance of suspecting gastrointestinal metastases in patients with pleomorphic lung cancer in the presence of nonspecific digestive symptoms.

[Duodenal bleeding due to metastasis from lung adenocarcinoma controlled by radiotherapy: A case report and literature review]

INTRODUCTION

Gastrointestinal (GI) metastases in lung cancer rarely occur.

CASE REPORT

We report here the case of a 43-year-old male active smoker who was admitted to our hospital for cough, abdominal pain and melena. Initial investigations revealed poorly differentiated adenocarcinoma of the superior-right lobe of the lung: positive for thyroid transcription factor-1 and negative for protein p40 and for antigen CD56, with peritoneal, adrenal and cerebral metastasis, as well as anemia requiring major transfusion support. Over 50% of cells were positive for PDL-1, and ALK gene rearrangement was detected. GI endoscopy showed a large ulcerated nodular lesion of the genu superius with active intermittent bleeding, as well as an undifferentiated carcinoma with positivity for CK AE1/AE3 and TTF-1, and negativity for CD117, corresponding to metastatic invasion originating from lung carcinoma. Palliative immunotherapy with pembrolizumab was proposed, followed by targeted therapy with brigatinib. Gastrointestinal bleeding was controlled with a single 8Gy dose of haemostatic radiotherapy.

CONCLUSION

GI metastases are rare in lung cancer and present nonspecific symptoms and signs but no characteristic endoscopic features. GI bleeding is a common revelatory complication. Pathological and immunohistological findings are critical to diagnosis. Local treatment is usually guided by the occurrence of complications. In addition to surgery and systemic therapies, palliative radiotherapy may contribute to bleeding control. However, it must be used cautiously, given a present-day lack of evidence and the pronounced radiosensitivity of certain gastrointestinal tract segments.

Successful control of intestinal bleeding from metastasis of pulmonary pleomorphic carcinoma with pembrolizumab: A case report

RATIONALE

Pulmonary pleomorphic carcinoma is a rare tumor with a poor prognosis and has no standard chemotherapy. We herein report a case of small intestinal metastasis of pulmonary pleomorphic carcinoma that resulted in intestinal bleeding and was successfully treated with pembrolizumab monotherapy.

PATIENT CONCERNS

A 54-year-old man with a history of pulmonary pleomorphic carcinoma resection was referred to our hospital due to a 1-month history of a fever and general fatigue.

DIAGNOSIS

Laboratory investigation revealed microcytic anemia. Hematochezia was also noted after admission. Computed tomography (CT) and positron emission tomography (PET)/CT at the time of this admission revealed intraperitoneal masses alongside the small intestine with no significant ascites.

INTERVENTIONS

Pembrolizumab (400 mg/body) was introduced as the first-line chemotherapy.

OUTCOMES

By the 15th day after the initial pembrolizumab administration, the fever had disappeared, and the intraperitoneal masses were markedly reduced. Hematochezia had also disappeared, and he no longer needed to receive blood transfusions.

LESSONS

To our knowledge, this is the first report in which small intestinal metastasis of pulmonary pleomorphic carcinoma was successfully controlled by pembrolizumab monotherapy. Immune checkpoint inhibitors may be promising therapeutic agents against pulmonary pleomorphic carcinoma.