pT1a renal cell carcinoma (RCC) is a relatively uncommon neoplasm, accounting for ∼2% of both global cancer diagnoses and deaths [1], however, its’ incidence is rising in developed countries [2]. While management is preferred via surgical resection, ablative techniques are indicated in select populations [3]. After surgical excision, whether radical or partial nephrectomy, robotic or open, 2% to 5% of patients with pT1a RCC pathology will experience recurrence with 50% to 60% of these being lung metastasis. While there is no consensus, the National Cancer Center Network (NCCN), American Urologic Association (AUA), and Canadian Urologic Association (CUA) recommended a chest x-ray (CXR) at least annually following treatment of localized RCC [3], [4], [5]. The European Association of Urology (EAU) does not feel CXR provides enough sensitivity, relative to computed tomography (CT) [6]. With the rare recurrence rates of pT1a RCC and low sensitivity of CXR, the ideal surveillance strategy is unknown.

Doornweerd et al. [7] evaluated the utility of chest x-ray (CXR) in RCC surveillance of stage pT1-T3 RCC after primary surgical management, with over 17-years follow-up, 221 patients were followed with 823 CXR performed, with only 7/823 (0.85%) being positive, leading to diagnosis of pulmonary recurrence. A similar retrospective study of patients who underwent resection or radiofrequency ablation evaluated 258 patients with pathology pT1a RCC. They demonstrated 3/258 patients (1.2%) developing pulmonary recurrence, with only 1/258 (0.4%) being diagnosed via CXR [8]. Leibovich et al. designed a stratification tool for predicting progression to metastasis after radical nephrectomy for RCC, based on tumor stage, size, nuclear grade, and presence of necrosis. Using this, the EUA has proposed a chest surveillance schedule strictly via CT, according to a patient's individualized risk profile [9]. Despite this data and knowledge of stage migration of RCC between 1980 and 2015 toward stage 1 pathology [10,11], national and international guidelines continue to recommend CXR for surveillance after localized RCC management.

With these data in mind, we attempted to fill this data gap by analyzing a larger cohort of patients’ postoperative chest surveillance for pT1 RCC after surgical resection. In those without baseline preoperative lung pathology, we hypothesize that there is questionable clinical value in the current surveillance protocol for pulmonary recurrence after resection of pT1a RCC.

We hypothesize that pT1a RCC managed via surgical resection, will result in a rare rate of positive CXR, leading to the diagnosis of pulmonary recurrence.