A case of pulmonary tumor thrombotic microangiopathy following lymphedema on the lower extremities

Abstract

Pulmonary tumor thrombotic microangiopathy (PTTM) is a rare manifestation of malignancy. The antemortem diagnosis is difficult, since patients present with rapidly progressive symptoms. We recently observed a case of PTTM following lymphedema of the lower extremities. We did not reach a diagnosis, even after performing BAL and TBLB. The patient manifested pulmonary hypertension and died on the 9th day of admission. Autopsy revealed a tumor embolism in the pulmonary arterioles accompanied by fibrocellular epithelial cell proliferation, but the primary organ was not identified. To our knowledge, this is the first reported case of PTTM with lymphedema.

Keywords: Adenocarcinoma; Lymphedema; PTTM; Pulmonary tumor thrombus microangiopathy; Unknown origin.

Fig. 1

Lymphoscintigraphy showed lymphatic leakage from the scrotum to the right lateral thigh and disturbance in the lymphatic drainage on both lower extremities.

Fig. 2

Chest X-ray on the patient's first visit shows mild infiltration in the bilateral middle and lower lung fields.

Fig. 3

(A) Chest high-resolution CT (HRCT) on the first day shows thickening of the broncho-vascular bundle, tree-in-bud appearance, and interlobular septal thickening. (B) HRCT obtained one day before his death showed a similar appearance to (A). It also showed mild cardiac hypertrophy and a small amount of pericardial effusion.

Fig. 4

Ultrasound cardiography from the short-axis view shows a D-shaped left ventricular (LV) cavity alongside a grossly hypertrophied right ventricle (RV).

Fig. 5

S1Q3T3 pattern and negative T wave in leads V1–V4 were seen on electrocardiography, which suggests pulmonary hypertension.

Fig. 6

The gross findings of the lung identified thickening of the interlobular septa and peribronchiolar connective tissue (as pointed by the yellow arrow), along with small hilar lymphadenopathies (as pointed by the red arrows). . (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)

Fig. 7

Histopathological findings. (A) Multiple lymphovascular invasion of adenocarcinoma is observed in the lung (HE, × 4, x400). (B) The specimens showed metastasis of the hilar lymph nodes, along with lymphatic invasion (HE, × 4). (C)(D) The lymphatic vessels around the adrenal glands (C) and liver capsule (D) were occupied by the same tumor cells (HE, C; × 40, D; x400). (E) Metastasis to the bilateral common iliac lymph nodes was identified (HE, x100). (F) In the small pulmonary arterioles, fibrocellular intimal proliferation and tumor embolism were apparent, resulting in stenosis (Elastica van Gieson staining, × 400).