CT Texture Analysis of Cervical Lymph Nodes on Contrast-Enhanced [18F] FDG-PET/CT Images to Differentiate Nodal Metastases from Reactive Lymphadenopathy in HIV-Positive Patients with Head and Neck Squamous Cell Carcinoma

H. Kuno; N. Garg; M.M. Qureshi; M.N. Chapman; B. Li; S.K. Meibom; M.T. Truong; K. Takumi; O. Sakai

doi:10.3174/ajnr.A5974

Article Figures & Data

Figures

Tables

Download figure
Open in new tab
Download powerpoint
Fig 1.
Flowchart shows patient selection for the study.
Download figure
Open in new tab
Download powerpoint
Fig 2.
Representative case of false-positive findings on FDG-PET for benign nodes in a 74-year-old woman with unknown primary squamous cell carcinoma who had both benign and malignant nodes (HIV-positive; absolute CD4 = 473). Axial contrast-enhanced CT images (A and D), [¹⁸F] FDG-PET/CT fusion images (B and E), and corresponding axial section ROI mask-segmented lymph nodes (C and F) for pathologically benign (A–C) and malignant (D–F) lymph nodes. [¹⁸F] FDG-PET/CT shows abnormal uptake (cutoff = >5.5) for both lymph nodes with SUVmax = 8.1 (benign, B) and 9.5 (malignant, E). However, texture features with SRE (cutoff = <0.164) of both lymph nodes were correctly diagnosed as follows: 0.188 (benign, C) and 0.151 (malignant, F).

Tables

Figures

View popup

Table 1:

Patient demographics and tumor characteristics of patients with head and neck cancer^{^a}

Characteristic	HIV-Positive Group (n = 9)	HIV-Negative Group (n = 26)	P Value
Age (yr)			.034^{^b}
Median (range)	48 (29–62)	59 (30–86)
Sex			.490
Male	7 (78)	17 (65)
Female	2 (22)	9 (35)
HPV status (protein 16)			.283
Positive	3	12
Negative	1	14
Unknown	5	0
Primary site			.169
Oropharynx	3 (33)	10 (38)
Hypopharynx	0 (0)	1 (4)
Larynx	1 (11)	3 (12)
Oral cavity	3 (33)	12 (46)
Primary unknown	1 (11)	0 (0)
Maxilla	1 (11)	0 (0)
T-Stage			.444
T0	1 (11)	0 (0)
T1	1 (11)	7 (27)
T2	3 (33)	9 (35)
T3	1 (11)	2 (8)
T4	3 (33)	8 (30)

Note:—HPV indicates human papillomavirus.
↵a Data are presented as number of patients with percentages in parentheses unless otherwise noted.
↵b Indicates a significant difference by the Pearson χ² or Mann-Whitney U test (P < .05).

View popup

Table 2:

[¹⁸F] FDG-PET/CT characteristics and selected texture parameters differentiating lymph node characterization in patients with HIV infection (group 1 vs 2)

Texture Parameter	Benign Nodes (n = 9)		Malignant Nodes (n = 13)		P Value^{^a}	Cutoff	AUC^{^b} (GLIMMROC)
Texture Parameter	Mean	SD	Mean	SD	P Value^{^a}	Cutoff	AUC^{^b} (GLIMMROC)
Node characteristics
Size (cm)	1.400	0.300	1.892	0.690	.024	<2.0	0.752
Volume (cm³)	0.547	0.363	2.535	2.218	.007	>0.76	0.889
SUVmax	5.111	1.610	8.562	3.886	.042	>5.5	0.803
Histogram
Mean	624.4	74.6	735.3	75.2	.017	>683.3	0.872
Median	774.0	217.9	1013.1	71.2	.018	>877.8	0.872
Second SD	93.76	28.70	59.85	19.19	.017	<76.3	0.872
Range	273.7	82.9	175.4	54.5	.017	<232.7	0.863
Geometric mean	199.6	44.7	272.8	63.8	.032	>237.3	0.829
SD 5	81.9	29.4	16.8	19.2	.018	<62.89	0.872
SD 9	99.7	49.3	19.5	17.3	.017	<63.16	0.889
GLCM
Contrast	113.1	20.2	84.1	16.9	.009	<97.7	0.889
Energy	0.036	0.019	0.081	0.047	.025	>0.047	0.812
Homogeneity	0.451	0.065	0.542	0.069	.020	>0.498	0.821
GLRL
SRE	0.177	0.007	0.157	0.009	<.001	<0.164	0.966^{^c}
LRE	0.197	0.010	0.173	0.012	.001	<0.186	0.957
GLN	0.183	0.009	0.160	0.011	.001	<0.172	0.949
RLN	0.196	0.010	0.173	0.012	.002	<0.184	0.932
LRHGE	224.6	51.8	300.0	68.7	.035	>261.8	0.863

Note:—GLIMMROC indicates generalized linear mixed model receiver operating characteristic.
↵a Indicates a significant difference by the mixed linear regression model (Proc MIXED) to adjust the variance-covariance matrix among multiple values recorded for each patient (P < .05).
↵b Using the generalized linear mixed model (GLIMMROC).
↵c The highest AUC among 41 texture features.

View popup

Table 3:

[¹⁸F] FDG-PET/CT characteristics and selected texture parameters differentiating lymph node characterization in patients with head and neck squamous cell carcinoma without HIV infection (group 3 vs 4)

Texture Parameter	Benign Nodes (n = 39)		Malignant Nodes (n = 22)		P Value^{^a}	Cutoff	AUC^{^b} (GLIMMROC)
Texture Parameter	Mean	SD	Mean	SD	P Value^{^a}	Cutoff	AUC^{^b} (GLIMMROC)
Node characteristics
Size (cm)	1.439	0.048	1.687	0.831	.079	DNC	0.643
Volume (cm³)	1.122	0.147	3.468	4.718	.001^{^c}	>2.599	0.702
SUVmax	3.228	0.315	6.438	4.811	.007^{^c}	>3.980	0.731
Histogram
Mean	670.6	68.4	751.8	137.3	.022^{^c}	>738.1	0.705
Geometric mean	225.9	50.6	297.6	124.5	.020^{^c}	>257.5	0.667
Harmonic mean	24.12	4.21	29.57	9.42	.020^{^c}	>25.5	0.678
IQR	1064.3	63.9	865.0	360.2	.022^{^c}	<1017.0	0.723
Fourth moment	8.71E+10	5.74E+09	9.41E+10	1.00E+10	.018^{^c}	>9.38E+10	0.698
GLCM
Contrast	102.5	18.2	81.8	28.3	.015^{^c}	<75.7	0.754
Energy	0.041	0.022	0.072	0.055	.034^{^c}	>0.058	0.712
Homogeneity	0.475	0.056	0.541	0.104	.029^{^c}	>0.528	0.735
GLRL
SRE	0.164	0.011	0.154	0.019	.036^{^c}	<0.153	0.695
RLN	0.183	0.014	0.170	0.023	.034^{^c}	<0.172	0.698
RHGE	254.2	77.2	367.0	193.6	.016^{^c}	>305.4	0.739
LRLGE	322.6	91.4	469.8	231.9	.006^{^c}	>397.1	0.759
LRHGE	246.2	60.5	352.7	168.8	.003^{^c}	>340.9	0.760^{^d}
Laws features
L1	1,130,272.9	280,670.9	876,676.6	413,942.2	.024^{^c}	<911,080.5	0.722

Note:—DNC indicates did not converge; IQR, interquartile range; GLIMMROC, generalized linear mixed model receiver operating characteristic.
↵a Indicates a significant difference by the mixed linear regression model (Proc MIXED) to adjust the variance-covariance matrix among multiple values recorded for each patient (P < .05).
↵b Using the generalized linear mixed model (GLIMMROC).
↵c Significant.
↵d The highest AUC among 41 texture features.