Table 1 Incident cases of malignant mesothelioma recorded by the Italian national mesothelioma registry (ReNaM) selected for the cluster analysis

Age class

0-54

1,046

9.6

450

10.3

55-64

2,646

24.1

856

19.7

65-74

4,015

36.6

1,404

32.2

75+

3,257

29.7

1,648

37.8

Period of diagnosis

1993-1996

1,042

9.5

382

8.8

1997-2000

2,271

20.7

884

20.3

2001-2004

3,706

33.8

1,503

34.5

2005-2008

3,945

36.0

1,589

36.4

Area

Northwest

5,158

47.1

2,423

55.6

Northeast

2,586

23.6

901

20.7

Centre

1,450

13.2

454

10.4

South & Islands

1,770

16.1

580

13.3

Diagnostic certainty

Definite

8,708

79.4

3,234

74.2

Probable

1,142

10.4

574

13.2

Possible

1,114

10.2

550

12.6

Site of lesion

Pleura

10,312

94.0

3,941

90.4

Peritoneum

579

5.3

403

9.3

Pericardium

26

0.2

14

0.3

Testis

47

0.4

-

-

Exposure ascertainment

Direct interview

4,585

41.8

1,401

32.2

Indirect interview

4,139

37.8

1,727

39.6

No interview

2,240

20.4

1,230

28.2

Type of exposure

Occupational, definite

4,987

45.5

526

12.1

Occupational, probable

890

8.1

112

2.6

Occupational, possible

1,291

11.8

402

9.2

Familial

76

0.7

446

10.2

Environmental

214

1.9

294

6.7

Other non-occupational

80

0.7

108

2.5

Unlikely

193

1.8

223

5.1

Unknown

993

9.1

1,017

23.3

Undefined

2,240

20.4

1,230

28.2

Total

10,964

4,358