World J Oncol

World Journal of Oncology, ISSN 1920-4531 print, 1920-454X online, Open Access

Article copyright, the authors; Journal compilation copyright, World J Oncol and Elmer Press Inc

Journal website https://www.wjon.org

Original Article

Volume 14, Number 5, October 2023, pages 358-370

The Olfaction Ability of Medical Detection Canine to Detect Prostate Cancer From Urine Samples: Progress Captured in Systematic Review and Meta-Analysis

Figure 1. PRISMA flow diagram used to identify the included literatures. PRISMA: Preferred Reporting Items for Systematic Reviews and Meta-Analysis.

Figure 2. (a, b) The estimated sensitivity (Sn) and specificity (Sp) value of the MDC in detecting PCa from urine samples. MDC: medical detection canine; PCa: prostate cancer; CI: confidence interval.

Figure 3. (a, b) The estimated positive likelihood ratio (LR) and negative LR of MDC in detecting PCa from urine samples. MDC: medical detection canine; PCa: prostate cancer; CI: confidence interval.

Figure 4. (a, b) The estimated diagnostic odd ratio (DOR) and area under the curve (AUC) value of MDC in detecting PCa from urine samples. SROC: summary receiver operating characteristics; MDC: medical detection canine; PCa: prostate cancer; CI: confidence interval.

**Table 1.** Summary of the Included Studies
Study	Dog training phase	Patient and sample (testing phase)
F: female; MDD: medical detection dog; NR: not reported; PCa: prostate cancer; PSA: prostate-specific antigen.
Cornu et al, 2011 [20]	Belgian Malinois; NR	A professional trainer + two assistants (none)	Clicker training (ball if accurate)	5 day/week, from October 2007 to June 2010 (± 16 months); double-blind	Undiluted urine of PCa and healthy individual (unblinded)	33 (12.1); 64.1 ± 7.1	33 (-); 63.2 ± 7.1	11.7 ± 15.1	8.3 ± 4.1
Elliker et al, 2014 [21]	Labrador (dog-A); 9-year-old	Multiple professional trainers + behavioral scientist (none)	Clicker training (food if accurate)	Two phases (familiarization and consolidation), trained for 5 months (dog-A) and 8 months (dog-B); double-blind	Urine of PCa and healthy individual	15 (0.0); 63.6 ± 6.4	45 (-); 57.7 ± 5.2	7.2 ± 4.6	< 0.5
	Border Collie (dog-B); 3-year-old
Guest et al, 2021 [22]	Female Labrador (Florin); 4-year-old	The dogs had been trained by MDD, UK and at a university hospital for ± 3 years	Unspecified rewarding training	22 training days for NR duration in each session from November 2015 to September 2018 (± 35 monthes); double-blind	Undiluted urine of PCa and healthy individual	7 (100.0); 65.5 (49 - 75)	20; 68.5 (45 - 80)	8.0 (3 - 76)	4.7 (1 - 18)
	Female Wire Haired Hungarian Viszla (Midas); 7-year-old						21; 68.5 (45 - 80)
Taverna et al, 2015 [19]	Female German Shepherd (Liu); 3-year-old	A veterinary surgeon, a professional trainer, and two assistants (none)	Clicker training (NR rewarding)	Four phases (each phase progress to more diluted control urine, from 50% (phase 1) to undiluted (phase 4); June 2012 to October 2012 (4 moths); double-blind	Undiluted urine of PCa patients (200) and healthy individual (230)	362 (16.6)	540 (18.8% F)	120 (33.1%) patients had PSA level > 2.5	418 (77.4%) patients had PSA level < 1.0
	Female German Shepherd (Zoe); 3-year-old
Urbanova et al, 2015 [18]	Female German Shepherd (Agata Jankari); 7-month-old	A group of trainers (prior basic obedience and scent work training)	Clicker training (treat if accurate)	Two phases (familiarization and consolidation), 4 - 5/session/week for 11 months; single-blind	Urine of PCa and healthy individual	45	25	NR

Table 1. Summary of the Included Studies

Study

Dog training phase

Patient and sample (testing phase)

Breed, gender, dog’s name, and age at the start of training

Trainer and prior training status

Program (rewarding)

Training phase count, session duration, period and in-training blinding status

Urine sample type and size (for training phase; PCA/control)

Sample size (% of Gleason ≥ 8 for PCa or % of female for control) and age (years)

PSA level (ng/mL)

PCa

Control

PCa

Control

F: female; MDD: medical detection dog; NR: not reported; PCa: prostate cancer; PSA: prostate-specific antigen.

Cornu et al, 2011 [20]

Belgian Malinois; NR

A professional trainer + two assistants (none)

Clicker training (ball if accurate)

5 day/week, from October 2007 to June 2010 (± 16 months); double-blind

Undiluted urine of PCa and healthy individual (unblinded)

33 (12.1); 64.1 ± 7.1

33 (-); 63.2 ± 7.1

11.7 ± 15.1

8.3 ± 4.1

Elliker et al, 2014 [21]

Labrador (dog-A); 9-year-old

Multiple professional trainers + behavioral scientist (none)

Clicker training (food if accurate)

Two phases (familiarization and consolidation), trained for 5 months (dog-A) and 8 months (dog-B); double-blind

Urine of PCa and healthy individual

15 (0.0); 63.6 ± 6.4

45 (-); 57.7 ± 5.2

7.2 ± 4.6

< 0.5

Border Collie (dog-B); 3-year-old

Guest et al, 2021 [22]

Female Labrador (Florin); 4-year-old

The dogs had been trained by MDD, UK and at a university hospital for ± 3 years

Unspecified rewarding training

22 training days for NR duration in each session from November 2015 to September 2018 (± 35 monthes); double-blind

Undiluted urine of PCa and healthy individual

7 (100.0); 65.5 (49 - 75)

20; 68.5 (45 - 80)

8.0 (3 - 76)

4.7 (1 - 18)

Female Wire Haired Hungarian Viszla (Midas); 7-year-old

21; 68.5 (45 - 80)

Taverna et al, 2015 [19]

Female German Shepherd (Liu); 3-year-old

A veterinary surgeon, a professional trainer, and two assistants (none)

Clicker training (NR rewarding)

Four phases (each phase progress to more diluted control urine, from 50% (phase 1) to undiluted (phase 4); June 2012 to October 2012 (4 moths); double-blind

Undiluted urine of PCa patients (200) and healthy individual (230)

362 (16.6)

540 (18.8% F)

120 (33.1%) patients had PSA level > 2.5

418 (77.4%) patients had PSA level < 1.0

Female German Shepherd (Zoe); 3-year-old

Urbanova et al, 2015 [18]

Female German Shepherd (Agata Jankari); 7-month-old

A group of trainers (prior basic obedience and scent work training)

Clicker training (treat if accurate)

Two phases (familiarization and consolidation), 4 - 5/session/week for 11 months; single-blind

Urine of PCa and healthy individual

**Table 2.** Risk of Bias of the Included Studies as Assessed in QUADAS-2 Tool
Study	Risk of bias	Applicability concerns
Cornu et al, 2011 [20]	Low-risk of bias	Low-risk of bias	Low-risk of bias	Unclear-risk of bias	Low-risk of bias	Low-risk of bias	Low-risk of bias
Elliker et al, 2014 [21]	Low-risk of bias	Low-risk of bias	Unclear-risk of bias	Low-risk of bias	Low-risk of bias	Low-risk of bias	Unclear-risk of bias
Guest et al, 2021 [22]	Low-risk of bias	Low-risk of bias	Low-risk of bias	High-risk of bias	Low-risk of bias	Low-risk of bias	Low-risk of bias
Taverna et al, 2015 [19]	Low-risk of bias	Low-risk of bias	Unclear-risk of bias	Low-risk of bias	Low-risk of bias	Low-risk of bias	High-risk of bias
Urbanova et al, 2015 [18]	Low-risk of bias	Low-risk of bias	Unclear-risk of bias	Low-risk of bias	Low-risk of bias	Low-risk of bias	Low-risk of bias

Table 2. Risk of Bias of the Included Studies as Assessed in QUADAS-2 Tool

Study

Risk of bias

Applicability concerns

Patient selection

Index test

Reference standard

Flow and timing

Patient selection

Index test

Reference standard

Cornu et al, 2011 [20]

Low-risk of bias

Unclear-risk of bias

Low-risk of bias

Elliker et al, 2014 [21]

Low-risk of bias

Unclear-risk of bias

Low-risk of bias

Unclear-risk of bias

Guest et al, 2021 [22]

Low-risk of bias

High-risk of bias

Low-risk of bias

Taverna et al, 2015 [19]

Low-risk of bias

Unclear-risk of bias

Low-risk of bias

High-risk of bias

Urbanova et al, 2015 [18]

Low-risk of bias

Unclear-risk of bias

Low-risk of bias