SSTR2 and small cell lung carcinoma: Furthermore, in addition to maximizing the radiation dose to specific target volumes, other benefits may be realized specific to NEN patients, as external beam radiation can upregulate the expression of SSTR2 and the uptake of radiolabeled SSA in neuroendocrine and small cell lung cancer cells (Oddstig et al. 2006), which may influence the appropriate timing of therapy.