Retention index of FDG-PET/CT SUVmax of the primary tumor in non-small cell lung cancer as a predictor of lymph node metastasis: a retrospective study

EJNMMI Reports

Table 2 Clinicopathological characteristics based on pathological N factor

Characteristics	Overall (n = 218)	pN 0 (n = 174)	pN 1 or 2 (n = 44)	p value
Sex
Male	140	108	32	0.22*
Female	78	66	12
Lobe
RU	67	56	11	0.17*
RM	13	9	4
RL	51	45	6
LU	41	31	10
LL	46	33	13
Histological type
Adenocarcinoma	145	116	29	0.43*
Squamous cell	53	44	9
Other	20	14	6
Clinical N stage
cN0	187	160	27	< 0.001*
cN1or2	31	14	17
Age, years	69.6 ± 9.5	69.5 ± 9.7	70.0 ± 8.5	0.73**
SUVmax_e	3.3 [1.73–6.58]	2.9 [1.40–5.78]	5.7 [3.6–7.68]	< 0.001***
SUVmax_d	4.2 [2.0– 8.68]	3.5 [1.45–7.70]	7.4 [4.35–10.58]	< 0.001***
RI	0.25 [0.08–0.37]	0.24 [0.01–0.36]	0.30 [0.23–0.39]	0.01***
pT, mm	22.0 [15.8–30.0]	21.0 [15.0–29.0]	25.5 [22.0–38.8]	< 0.001***

Data are presented as n (%), mean ± standard deviation, or median [interquartile ranges]
^*Fisher's exact test; **unpaired t test; ***Mann–Whitney U test
pN pathological lymph node metastasis, RU right upper lung lobe, RL right lower lung lobe, RM right middle lung lobe, LU left upper lung lobe, LL left lower lung lobe, SUVmax_e early maximum standardized uptake value, SUVmax_d delayed maximum standardized uptake value, RI retention index, pT pathological tumor size