Table 4.

Scheme of the studies regarding cancer diseases.

Reference Number	Main Author	E-Nose Type	Patho-Logies	Sample Preparation Method	Results	Sample
[59]	Bernabei et al.	ENQBE	PC, BC	Urines collected in the morning, before any food intake. Stored at 25 °C for the necessary time to obtain a steady headspace. 10 mL of the headspace injected into a 2 L sterile bag pre-filled with N2	(1)PLS-DA→ discrimination between the patients and to the healthy controls 100%. (2)PCA→not a complete discrimination between the two tumors, but a sort of gradual differentiation (3)PCA→migration of post-surgery patients towards the healthy class	131: 25 BC, 12 PC, 29 BPH, 33 various urological pathologies, 18 healthy control (19 patients measured twice, before and after the surgical treatment of cancer)
[60]	Weber et al.	NST 3320 Lab Emission Analyser	BC	Storage at −80 °C, defrosted at room temperature (21 °C). samples aliquoted into vials and incubated for 1 h at 38 °C	(1)PLS-DA→healthy volunteers vs. bladder cancer patients: sensitivity 70%, specificity 70% (2)PLS-DA→data of healthy controls suffer from other non-cancerous urological diseases: classification accuracy 65%, sensitivity 60%, specificity 67%	89: 30 patients with BC, 59 healthy control
[61]	Horstmann et al.	e-nose based on a MOS sensor	BC	-	PCA→sensitivity 75%, specificity 86%	36: 15 BC 21 healthy control (with no pathologies or benign urological conditions like BPH and UTI)
[62]	D’Amico	e-nose University of Rome “Tor Vergata”	PC	Samples collected in sterile urine boxes with a dedicated top to extract the headspace of urine for analysis. No more information are reported	PLS-DA→the results reported are only qualitative; data regarding classification accuracy, sensitivity and specificity of the adopted method are not discussed	21
[63]	Santonico et al.	e-nose University of Rome “Tor Vergata”	PC	Measurements performed at room temperature. No more information are reported	PLS-DA→the results reported are only qualitative, no quantitative data are provided about the adopted method	41: 27 healthy control, 14 PC
[64]	Asimakopoulos et al.	e-nose University of Rome “Tor Vergata	PC	Measurement performed within 2 h from the collection	PLS-DA→sensitivity 71.4%, specificity 92.6%	41
[65]	Roine et al.	ChemPro 100-eNose	PC	Sample defrosted and pipetted to a plate heated and maintained at 37 °C	-LOOCV→sensitivity 78%, specificity 67% -LDA→sensitivity 82%, specificity 88%	74: 50 PC; 24 healthy control (15 BPH, 9 patients provided samples 3 months postoperatively)
[66]	Westenbrink et al.	WOLF system	CRC	Storage at −80 °C, defrosted overnight at 5 °C. Samples heated to 40 °C for 5 min	LDA→sensitivity 78%, specificity 79%	92: 39 CRC; 35 IBS; 18 healthy control