Abstract Introduction Upper urinary tract urothelial carcinoma (UTUC) is a highly aggressive malignancy, comprising only 5% of urothelial carcinomas. Most guidelines are derived from urothelial carcinoma of the bladder (UCB) (1). 13% of primary UTUC cases documented in the SEER database developed distant metastases (2). However, distant metastases are usually seen with cancer recurrence (3). Isolated pulmonary metastasis from UTUC is rarely seen. We report a rare case of primary UTUC with distant pulmonary metastases on initial presentation. Case Summary A 77-year-old female with past medical history of systemic lupus erythematosis and nephrolithiasis presented with progressive dry cough, shortness of breath, and mild hypoxia (O2% 96). Two weeks prior to this admission, she was seen for heart failure exacerbation. Despite appropriate medical management, her cough and dyspnea persisted. CTA chest revealed innumerable bulky pulmonary nodules and masses, the largest in the lower lobes; as well as hilar, perihilar, and subcarinal lymphadenopathy, indicative of metastatic carcinoma. Upon further questioning the patient noted a several-week history of painless hematuria despite a trial of antibiotics. CTA abdomen/pelvis revealed right kidney hydronephrosis, and significant edema concerning for pyelonephritis or underlying malignancy. There was no evidence of any lymphadenopathy or abdominal metastasis. Endobronchial ultrasound (EBUS) directed core biopsy of the station 7 lymph node yielded scant lymphoid elements and fibrinous material. CT-guided biopsy of one of lung masses revealed metastatic urothelial carcinoma. Immunohistochemistry was notable for pancytokeratin, p40, GATA3, CK7, and CK20; it was negative for TTF-1 and INSM1, supporting the diagnosis of UTUC. PET scan confirmed no other sites of malignancy beyond the innumerable pulmonary nodules and the right kidney. She developed post-obstructive pneumonia one month later, and opted for home hospice. Discussion This patient had UTUC of the right kidney, with metastases confined to the thorax. Much of the literature on UTUC is extrapolated from studies conducted in urothelial carcinoma of the bladder (1). Pulmonary manifestations of UC as the presenting symptom are rare, and most cases of pulmonary metastasis present with recurrence (4). UTUC comprises only 5-10% of all urothelial carcinomas, of which 13% develop distant metastases. GATA3 positivity further differentiates metastatic UC from other primary or secondary malignancies, and tumor burden indicates significant duration of disease (3). There are only 2 other cases of pulmonary metastases from UTUC in our literature review, both in cases of recurrence. Although extremely rare, awareness of UTUC pulmonary metastasis could guide long-term follow up. This abstract is funded by: none
Shakir et al. (Fri,) studied this question.