Management of oligometastatic non-small cell lung cancer patients: Current controversies and future directions

Table 1 Prospective trials of local treatment in oligometastatic disease

Author	n	Primary site, n	Treatment groups	Type of treatment	Endpoints	Toxicity
Rusthoven et al[7], 2009	47	CRC: 15; Lung: 10; breast: 4; other: 10	SBRT	Phase I: 36-60 Gy in 3 fx; Phase II: 60 Gy in 3 fx.	LC 2 yr: 92%; OS 2 yr: 30%	G3: 2%; No RILD
Salama et al[29], 2011	61	NSCLC: 11; SCLC: 5; H&N: 5. Other: 40	SBRT	3 fx: 8 Gy 3 fx: 20 Gy	MFu: 20.9 mo; PFS 2 yr: 22%; OS 2 yr: 56.7%	G3 (n = 2)
Iyengar et al[88], 2014	24	NSCLC	SBRT: 1 fx: 19-24 Gy; 3 fx: 27-33 Gy; 5 fx: 35-40 Gy	SBRT + erlotinib	MFU: 11.6 mo; PFS: 14.7 mo;; OS: 20.4 mo	G3 (n = 2); G4 (n = 1); G5 (n = 1) (after SBRT to three sites)
Collen et al[104], 2014	26	NSCLC	SBRT after primary treatment	50 Gy in 10 fx	MFu: 16.4 mo; PFS 1 yr: 45%, median 11.2 mo; OS 1 yr: 67%	G2: 15% G3: 8% (n = 2)
Gomez et al[33], 2018	49	NSCLC	LCT (CRT/Surgery of all lesions) vs maintenance therapy/obs.	SBRT n = 5; Surgery n = 3; pemetrexed n = 16, erlotinib n = 2; afatinib n = 1, bevacizumab	Median PFS: 14.2 mo/4.4 mo (P < 0.05) Median OS: 41.2 mo/17.0 mo (P < 0.05)	Similar, G3
Iyengar et al[31], 2018	29	NSCLC	Maintenance Ct alone vs SBRT followed by maintenance Ct	Ct: carboplatin + pemetrexed; SBRT: 1, 3 and 5 fractions with 21-27 Gy, 26.5-33 GY and 30-37.5 Gy respectively	MFu: 9.6 mo Median PFS: -Ct: 3.5 mo -SBRT: 9.7 mo (P < 0.05); Median OS: - no difference	G3 n: 4 vs 2; G4 n: 1 (ct only); G5 n: 3 vs 6. No grade 3 or higher toxicity attributable to SBRT
De Ruysscher et al[30], 2018	40	NSCLC	Primary: RT or CRT, LCT (surgery, SBRT)	SBRT: 54 Gy of bone metastases. CNS: 1 fx: 8-20 Gy single or 24 Gy × 3 fx. PORT: 60 Gy	Median OS: 13.5 mo; 2-6 yr OS: 23.3%-10.3% Median PFS: 12.1 mo; 2-6 yr PFS: 51.3%-2.5%	G3 esophagitis: 15%; > G4: 0%

CRC: Colorectal cancer; NSCLC: Non-small cell lung cancer; SCLC: Small cell lung cancer; CNS: Central nervous system; ECOG: Eastern Cooperative Oncology Group; PORT: Postoperative radiotherapy; PFS: Progression-free survival; MFU: Median follow up; OS: Overall survival; LCT: Local consolidative therapy; Ct: Chemotherapy; RT: Radiotherapy; fx: Fraction; CRT: Chemoradiotherapy; SBRT: Stereotactic body radiotherapy; LC: Local control; RILD: Radiation-induced liver disease; H&N: Head and neck.