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Mean first passage time,usually defined as the average of the time for a randomly moving particle starting from a stable state to take before crossing some threshold,is an important respect in noise-induced escape problem.Fluctuations,as a result of the external environment,medical therapy and so on,are inevitable in the process of tumor growth.The investigations on the dynamic properties of the tumor growth system triggered by noise such as the noise-induced escape and noise-induced transition have attracted wide interest in fields varying from applied mathematics,biologists and physicians etc.Here we take a general non spatially-structured model of tumor growth at the tissue level into consideration and it is given by dN/dt=k/αN(1-(N/θ)α)'((t=0)=N)'where k > 0 represents the net rate at which tumor cells proliferate andθ > 0 denotes the carrying capacity.Compared to the classical logistic growth model,the advantage of this model lays that it can describe the phenomenological change in tumor's volume which varies between different tumors and patients by selecting the optimal parameterα.In this work we explore the mean first passage time for this general tumor growth model with Non-Gaussian colored noise under different parameter condition ofα.The functional methods including path integration and singular perturbation analysis are adopted to calculate the mean first passage time escaping from the stable equilibrium state,and the accuracy is also checked by comparing the analytic result with that obtained from Meant-Carlo simulations.Based on the derived analytic results,the effect of the non-Gaussian noise on the MFPT is disclosed.This study might provide a theoretical clue for estimating the medical therapy and radiotherapy cycles based on the mean first passage time,which has been believed to improve the efficacy of the clinical treatment with tumor at some extent.