[Primary large cell neuroendocrine carcinoma of pulmonary artery: a case report and literature review].
Kong Y, Liu F, et al. • Zhonghua jie he he hu xi za zhi = Zhonghua jiehe he huxi zazhi = Chinese journal of tuberculosis and respiratory diseases • 2026
Primary pulmonary artery LCNEC lacks specific clinical manifestations and is easily misdiagnosed as pulmonary embolism or pulmonary artery sarcoma, but radical surgery combined with platinum-based chemotherapy constitutes the mainstay of treatment, and multiline comprehensive treatment may offer prolonged survival benefits.
Key Findings
Results
Primary pulmonary artery large cell neuroendocrine carcinoma (LCNEC) can present as anticoagulation-refractory 'pulmonary embolism,' leading to initial misdiagnosis.
The patient initially presented with anticoagulation-refractory pulmonary embolism symptoms before the correct diagnosis was established.
The disease is noted to be easily misdiagnosed as pulmonary embolism or pulmonary artery sarcoma due to lack of specific clinical manifestations.
Diagnosis was confirmed only after pulmonary endarterectomy was performed.
Results
A 59-year-old male with pulmonary artery LCNEC was found to harbor a compound NRAS exon 3 mutation on molecular pathological analysis.
The patient was 59 years old and male.
Molecular pathological analysis identified a compound NRAS exon 3 mutation.
This molecular finding provided a basis for personalized therapy decisions.
NRAS exon 3 mutations have not been previously reported in this context, given the extreme rarity of the disease.
Results
The patient achieved an overall survival exceeding 33 months following multiline treatment including surgery, chemotherapy, immunotherapy, and targeted therapy.
Treatment sequence included: first-line etoposide plus cisplatin (EP regimen), second-line irinotecan, and third-line combination therapy of serplulimab (anti-PD-1), anlotinib (anti-angiogenic), and temozolomide.
At last follow-up, overall survival exceeded 33 months.
Radical surgery (pulmonary endarterectomy) was the initial treatment modality.
The authors conclude that 'multiline comprehensive treatment may offer prolonged survival benefits for patients.'
Results
Primary pulmonary artery LCNEC is an extremely rare disease, with only one similar reported case identified in the entire literature review.
A systematic search of domestic and international databases identified only one similar previously reported case.
The literature review summarized clinical presentations, pathological characteristics, molecular markers, and therapeutic advances.
The extreme rarity of the disease contributes to challenges in diagnosis and management.
Conclusions
Radical surgery combined with platinum-based chemotherapy constitutes the mainstay of treatment for primary pulmonary artery LCNEC.
Pulmonary endarterectomy was used as the surgical approach in the reported case.
Platinum-based chemotherapy (EP regimen: etoposide plus cisplatin) was administered as first-line systemic therapy.
Molecular testing is recommended to provide a basis for personalized therapy.
The authors recommend multiline comprehensive treatment for potentially prolonged survival benefits.
What This Means
This research describes a rare cancer called large cell neuroendocrine carcinoma (LCNEC) that originated in the pulmonary artery (the large blood vessel carrying blood from the heart to the lungs). The case involved a 59-year-old man who appeared to have a pulmonary embolism (blood clot in the lung arteries) that did not respond to blood thinners. Only after surgery to remove the obstruction was the true diagnosis of cancer revealed. A search of all available medical literature found only one other similar case ever reported, confirming how extraordinarily rare this condition is.
This research suggests that primary pulmonary artery LCNEC is easily confused with more common conditions like pulmonary embolism or a type of artery tumor called pulmonary artery sarcoma. In this patient, genetic testing of the tumor tissue identified a specific mutation (in a gene called NRAS), which helped guide treatment decisions. The patient was treated with multiple rounds of different therapies — starting with standard chemotherapy, then a different chemotherapy drug, and finally a combination of an immunotherapy drug (serplulimab), a targeted anti-cancer drug (anlotinib), and another chemotherapy (temozolomide) — and was still alive more than 33 months after diagnosis.
This research suggests that when patients have pulmonary artery obstruction that does not respond to blood thinners, clinicians should consider rare cancer diagnoses. Early surgical removal followed by chemotherapy appears to be the primary treatment approach, and molecular (genetic) testing of the tumor may open doors to additional personalized treatment options. The use of multiple lines of therapy over time may help extend survival for patients with this otherwise difficult-to-treat cancer.
Kong Y, Liu F, Wang S, Long H, Zheng L, Zhen Y, et al.. (2026). [Primary large cell neuroendocrine carcinoma of pulmonary artery: a case report and literature review].. Zhonghua jie he he hu xi za zhi = Zhonghua jiehe he huxi zazhi = Chinese journal of tuberculosis and respiratory diseases. https://doi.org/10.3760/cma.j.cn112147-20251205-00767