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PurposeRenal cell carcinoma with sarcomatoid dedifferentiation (sRCC) is an aggressive malignancy associated with a poor prognosis. Although existing literature focuses on patients presenting with metastatic disease, characteristics and outcomes for patients with localized disease are not well described. We aimed to evaluate postnephrectomy characteristics, outcomes, and predictors of survival in patients with sRCC who presented with clinically localized disease.Patients and methodsAn institutional review board-approved review from 1986 to 2011 identified 77 patients who presented with clinically localized disease, underwent nephrectomy, and had sRCC in their primary kidney tumor. Clinical and pathologic variables were captured for each patient. Overall survival (OS) and recurrence-free survival (RFS) were calculated for all patients and those who had no evidence of disease (NED) following nephrectomy, respectively. Comparisons were made with categorical groupings in proportional hazards regression models for univariable and multivariable analyses.ResultsOS for the entire cohort (n = 77) at 2 years was 50%. A total of 56 (77%) patients of the 73 who has NED following nephrectomy experienced a recurrence, with a median time to recurrence of 26.2 months. On multivariable analysis, tumor stage, pathologically positive lymph nodes, and year of nephrectomy were significant predictors of both OS and recurrence-free survival. Limitations include the retrospective nature of this study and relatively small sample size.ConclusionsLong-term survival for patients with sRCC, even in clinically localized disease, is poor. Aggressive surveillance of those who have NED following nephrectomy is essential, and further prospective studies evaluating the benefit of adjuvant systemic therapies in this cohort are warranted.

Reactive intermediates such as reactive nitrogen species play essential roles in the cell as signaling molecules but, in excess, constitute a major source of cellular damage. We found that nitrosative stress induced by steady-state nitric oxide (NO) caused rapid activation of an ATM damage-response pathway leading to downstream signaling by this stress kinase to LKB1 and AMPK kinases, and activation of the TSC tumor suppressor. As a result, in an ATM-, LKB1-, TSC-dependent fashion, mTORC1 was repressed, as evidenced by decreased phosphorylation of S6K, 4E-BP1, and ULK1, direct targets of the mTORC1 kinase. Decreased ULK1 phosphorylation by mTORC1 at S757 and activation of AMPK to phosphorylate ULK1 at S317 in response to nitrosative stress resulted in increased autophagy: the LC3-II/LC3-I ratio increased as did GFP-LC3 puncta and acidic vesicles; p62 levels decreased in a lysosome-dependent manner, confirming an NO-induced increase in autophagic flux. Induction of autophagy by NO correlated with loss of cell viability, suggesting that, in this setting, autophagy was functioning primarily as a cytotoxic response to excess nitrosative stress. These data identify a nitrosative-stress signaling pathway that engages ATM and the LKB1 and TSC2 tumor suppressors to repress mTORC1 and regulate autophagy. As cancer cells are particularly sensitive to nitrosative stress, these data open another path for therapies capitalizing on the ability of reactive nitrogen species to induce autophagy-mediated cell death., National Institutes of Health (U.S.) (Grant RO1 CA143811), National Institutes of Health (U.S.) (Grant 5 P01 CA26731), National Institutes of Health (U.S.) (Grant ES002109)