Pulmonary tumor embolisms (PTEs) are primarily caused by adenocarcinoma. However, only a few cases of oropharyngeal carcinoma have been reported. We herein report a 47-year-old man who presented with a fever, cough, and dyspnea 6 months after treatment for stage II oropharyngeal carcinoma. Chest computed tomography revealed centrilobular granular and nodular shadows and subpleural consolidation. A transbronchial lung biopsy revealed a mass of squamous tumor cells forming emboli in the small vessels, resulting in the diagnosis of PTE due to oropharyngeal carcinoma. Therefore, PTE should be considered for patients with a history of hypoxia.

Polycystic ovary syndrome (PCOS) is the leading cause of endocrine disorders among females of reproductive age and is linked with autoimmune disorders. PCOS has been associated with autoantibodies such as antinuclear antibody (ANA), anti-thyroid, and anti-Smith (anti-SM). Young patients with PCOS and systemic lupus erythematosus (SLE) have up to a 10-fold increase in stroke. We present a case of a patient with a history of PCOS (on metformin), hypothyroidism, and pulmonary embolism who presented to the emergency room with acute left-sided weakness. She was extensively investigated for risk factors and was eventually diagnosed with a cerebrovascular accident secondary to possible SLE with positive ANA (1:160, nuclear homogenous pattern). The diagnosis of PCOS, coupled with autoantibodies and recurring episodes of thromboembolic events, rendered her case management complex. She received tenecteplase and had thrombectomy done twice because of recurrent thrombotic events during her hospital stay. She passed away on the fifth day post-thrombectomy from a possible massive pulmonary embolism with hemodynamic compromise. There is a need for more research to comprehend the underlying mechanisms of SLE and PCOS to guide the proper management of patients in this situation.

Pulmonary tumor embolism (PTE) is difficult to diagnose before death. We report the case of a 75-year-old man with microscopic PTE of renal cell carcinoma who was diagnosed by surgical lung biopsy. He visited our hospital because of dyspnea on exertion. Chest computed tomography (CT) showed multiple micronodules and ground glass opacities. Steroid therapy was started as therapeutic diagnosis for IgG4-related pulmonary disease. However, he was admitted our hospital due to progressive respiratory failure. Pathological findings of a lung biopsy obtained by video-assisted thoracic surgery showed PTE of renal cell carcinoma without embolization of large pulmonary arteries. He received palliative medicine and died four months after the surgical lung biopsy. In cases of multiple micronodules in chest CT findings and worsened respiratory symptoms, PTE should be considered in the differential diagnosis.

Pulmonary tumor embolism (PTE) and pulmonary tumor thrombotic microangiopathy (PTTM) are rare etiologies for rapidly progressive dyspnea in the setting of undiagnosed metastatic cancer. They occur most frequently in association with adenocarcinomas, with PTE being most frequently associated with hepatocellular carcinoma and PTTM being most commonly reported with gastric adenocarcinoma. Pulmonary tumor embolism and PTTM appear to be a disease spectrum where PTTM represents an advanced form of PTE. Pulmonary tumor embolism and PTTM are mostly identified postmortem during autopsy as the antemortem diagnosis remains a clinical challenge due to the rapidly progressive nature of these rare diseases. We report 2 cases of rapidly progressive respiratory failure leading to death, due to tumoral pulmonary hypertension resulting from PTE and PTTM, diagnosed postmortem. Both of the patients were middle-aged females, nonsmokers, and had a gastrointestinal source of their primary malignancy.

A 74-year-old man with chronic obstructive pulmonary disease on home oxygen and coronary artery disease was transferred from an outside facility to obtain an inguinal lymph node biopsy to rule out malignancy. He underwent an uncomplicated procedure and was discharged the same day. While waiting for transportation, he had sudden-onset dyspnea and collapsed. After resuscitation, patient had return of spontaneous circulation and was admitted but was provided comfort care and soon expired. Autopsy showed metastatic squamous cell carcinoma with multiple bilateral tumor emboli. Pulmonary tumor embolism is a rare cause of dyspnea in cancer population. Most of the cases are diagnosed with autopsy after sudden death; however, few cases have been reported antemortem. Tumor embolism is rare and difficult to diagnose without an autopsy with a poor outcome.

Acute distress immediately following an 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) scan is an exceedingly rare event. We report a case whose condition was suddenly deteriorated in the nuclear medicine laboratory, and whose diagnosis was confirmed by FDG-PET/CT. A 67-year-old woman with left renal cell carcinoma (RCC) suddenly complained of dyspnea and tachycardia just after undergoing FDG-PET/CT. PET/CT images showed increased FDG uptakes in the left renal vein, inferior vena cava, right atrium, and bilateral hila. She was diagnosed with a massive tumor embolism from the inferior vena cava to both pulmonary arteries, and urgently underwent tumor embolectomy. FDG-PET/CT was helpful for diagnosing the tumor embolism and differentiating it from bland thromboembolism in this patient with RCC.

Tumor lysis syndrome (TLS) is an oncological life-threatening complication characterized by hyperuricemia, hyperphosphatemia, and hyperkalemia, which can lead to acute renal failure, cardiac arrhythmias, cardiac arrest and seizures. Although TLS is a rare complication in patients with non-hematological malignancy, the mortality rate of TLS in solid tumors is higher than that in hematological malignancies. Acute renal injury is the most common cause of mortality associated with TLS in solid tumors. We report a case of TLS following chemotherapy for a recurrent uterine serous carcinoma. In this case, we speculated that the cause of death might be a pulmonary tumor embolism caused by TLS.

We report on a case of pulmonary tumor embolism caused by squamous cell carcinoma of the uterine cervix.
A 60-year-old female diagnosed with stage IVB (cT4N1M1) squamous cell carcinoma of the uterine cervix was admitted to our institution with a chief complaint of progressive dyspnea that developed within a few days after admission.
A chest CT scan showed dilated pulmonary arteries, right ventricular enlargement and mosaic ground-glass opacities in both lungs. An echocardiogram revealed elevated right ventricular pressure and a floppy mass in the right ventricle. Pulmonary tumor embolism was highly suspected. However, she died from respiratory failure on the fourth day after admission. Autopsy revealed diffuse tumor emboli in bilateral pulmonary arteries and arterioles.
Pulmonary tumor embolism should be considered when patients with malignant disease develop unexplained dyspnea, hypoxemia, and pulmonary hypertension.

Peripheral primitive neuroectodermal tumor (PNET) of the kidney is a rare, aggressive tumor known for its recurrence and metastatic potential. Despite the frequency of venous extension to the renal veins and inferior vena cava, pulmonary tumor embolism at the initial presentation is not common. We report a case of 22-year-old female with PNET of the kidney who presented with tumor embolism in the inferior vena cava (IVC) and bilateral pulmonary artery. The patient underwent surgical resection and histopathological analysis confirmed the presence of tumor within the IVC and pulmonary arteries. The patient received adjuvant chemotherapy and is currently doing well on follow-up.