Tumor Emboli: A Rare Cause of Acute Pulmonary Hypertension

Loose Tumor Cells in Pulmonary Arteries of Lung Adenocarcinoma Resection Specimens: No Correlation With Survival, Despite High Prevalence

CONTEXT

Loose tumor cells and tumor cell clusters can be recognized in the lumen of intratumoral pulmonary arteries of resected non-small cell lung cancer specimens. It is unclear whether these should be considered tumor-emboli, and as such could predict a worsened prognosis.

OBJECTIVE

To investigate the nature and prognostic impact of pulmonary artery intraluminal tumor cells.

DESIGN

This multicenter study involved an exploratory pilot study and a validation study from 3 institutions. For the exploratory pilot study, a retrospective pulmonary resection cohort of primary adenocarcinomas, diagnosed between November 2007 and November 2010, were scored for the presence of tumor cells, as well as potentially other cells in the intravascular spaces, using hematoxylin-eosin and cytokeratin 7 (CK7) stains. In the validation part, 2 retrospective cohorts of resected pulmonary adenocarcinomas, between January 2011 and December 2016, were included. Recurrence-free survival (RFS) and overall survival (OS) data were collected.

RESULTS

In the pilot study, CK7+ intravascular cells, mainly tumor cells, were present in 23 of 33 patients (69.7%). The 5-year OS for patients with intravascular tumor cells was 61%, compared with 40% for patients without intravascular tumor cells (P = .19). In the validation study, CK7+ intravascular tumor cells were present in 41 of 70 patients (58.6%). The 5-year RFS for patients with intravascular tumor cells was 80.0%, compared with 80.6% in patients without intravascular tumor cells (P = .52). The 5-year OS rates were, respectively, 82.8% and 71.6% (P = .16).

CONCLUSIONS

Loose tumor cells in pulmonary arterial lumina were found in most non-small cell lung cancer resection specimens and were not associated with a worse RFS or OS. Therefore, most probably they represent an artifact.

Microscopic pulmonary tumor embolism from adenocarcinoma of the prostate

INTRODUCTION

Microscopic pulmonary tumor embolisms from prostate cancer are extremely rare. In this case of prostate cancer, microscopic pulmonary tumor embolism developed during androgen deprivation therapy.

CASE PRESENTATION

A 56-year-old man was diagnosed with prostate cancer and underwent androgen deprivation therapy. Three months after starting treatment, he noticed shortness of breath and developed acute progressive dyspnea. He was diagnosed with pulmonary hypertension; however, the cause was not found. His dyspnea was progressive and he died 40 days after the onset of symptoms. Autopsy proved that the cause of pulmonary hypertension was microscopic pulmonary tumor emboli from prostate cancer. Furthermore, histology revealed differences in the androgen receptors in the prostate and emboli, with significantly greater Ki-67 expression in the emboli than in the prostate.

CONCLUSION

Prostate cancer proliferated in the pulmonary artery after hematogenous metastasis, caused vascular occlusion, and formed microscopic pulmonary tumor embolisms.