Occult Gastric Cancer Presenting as Hypoxia from Pulmonary Tumor Thrombotic Microangiopathy

Abstract

Pulmonary tumor thrombotic microangiopathy (PTTM) causing fatal pulmonary hypertension is a rare presentation of malignancy. In general, patients with PTTM rapidly succumb to death due to severe hypoxia. To date, very few cases of PTTM have been reported in the literature; and most of these cases were from gastric cancer and were diagnosed on post mortem autopsy, as it is extremely challenging to make an ante mortem diagnosis. We here report on a case of undiagnosed diffuse gastric cancer, presenting as worsening hypoxia. The clinical, radiographic, and echocardiographic features, and laboratory and pathological results were consistent with PTTM from gastric cancer. The patient was started on anticoagulation therapy, corticosteroids, and high-flow oxygen. However, her hypoxia worsened to the extent that she required ventilator support, and she died soon after intubation due to cardiac arrest. Since diffuse gastric cancer is associated with hereditary diffuse gastric cancer syndrome, cadherin 1 gene mutation analysis was performed to estimate the risk to her daughters. The test came back negative.

A case of pulmonary tumour thrombotic microangiopathy

“…It presents in a similar fashion to respiratory diseases such as pulmonary thromboembolism, pulmonary hypertension, or pneumonia. Typically there is evidence of metastatic disease at the time of presentation [6] , but occult cancer manifested as pulmonary thrombotic microangiopathy is more rarely reported, as in this case.…”

Fatal Pulmonary Tumour Thrombotic Microangiopathy (PTTM) Associated with Signet Ring Cell Carcinoma of Colon: An Autopsy Diagnosis

“…Typically there is diagnosis of a metastatic disease at the time of presentation of PTTM [11], but occult cancer presented as PTTM can be noted albeit rarely, as found in our case.…”

Ante-mortem diagnosis of pulmonary tumour thrombotic microangiopathy in a patient with unrecognised extramammary Paget's disease

“…Chemotherapy is an alternative option, and has shown some success in two cases 10 11. A search of full-text case reports written in English identified 19 patients who were diagnosed antemortem, including seven who underwent transbronchial lung biopsy (TBLB),2 7 9 11 12 five who received video-assisted thoracoscopic surgery or thoracotomy (including 1 patient who was not diagnosed by TBLB),2 8 10 13 14 one patient who underwent CT-guided biopsy,2 four diagnosed by cytology,2 6 15 16 and two cases who were diagnosed based on clinical decisions without specific pathological testing 17 18. The treatment and survival of these cases are shown in table 1.…”