Table 1 PNI-GARS

Definitely benign

0

No pulmonary nodules OR Pure calcified nodules, nodules with fat component, spherical atelectasis, perifissural nodules

No special treatment. Annual follow-up with LDCT for high-risk groups.

-

Benign

I

Micronodule with any density: ≤5 mm; Solid nodules > 5 mm and unchanged ≥ 2 years; Sub solid nodules > 5 mm and unchanged ≥ 5 years, the lesions decreased (but not increase in density) or disappeared during follow-up

LDCT 12 months, and if the nodule absorbs or shrinks, there is no need to pay attention. If the nodule increases, management is proceeded as Grade II.

-

Probably Benign

II

5 ~ 8 mm,partial edge smooth.

5 ~ 6 mm, LDCT 6months; 6 ~ 8 mm, LDCT 3 months. Nodules shrink and management is proceeded as Grade I. Nodules become larger and management is proceed as Grade IIIa. Nodules are enlarged with early malignant signs, and management is proceed as Grade IV. Nodules remain unchanged, and the follow-up time was doubled.

Very low probability

Probably Malignant

III

8 ~ 30 mm(≤ 30 mm); Partial solid nodules ( solid component ≤ 5 mm); Endobronchial nodules

Further examination or LDCT 1 month

-

IIIa

Small nodules: 8 ~ 10 mm; GradeII nodules with malignant signs such as vacuole, vascular convergence, lobulation, etc.

LDCT 1 month

Medium probability

IIIb

Medium nodules: 10 ~ 20 mm;Grade IIIa nodules with malignant signs such as vacuole, vascular convergence, lobulation, etc.

Tumour markers, PET/CT(solid component ≥ 8 mm), Percutaneous lung biopsy, Bronchoscope. Thoracoscopic resection is recommended if the auxiliary examination is positive or the pulmonary nodules seriously affect the patient’s life. Nodules with early malignant signs were classified as Grade IV. Endobronchial nodules are recommended for LDCT 1 month later. If there is no change, bronchoscope is recommended.

High probability

IIIc

Large nodules: 20 ~ 30 mm;Grade IIIb nodules with malignant signs such as vacuole, vascular convergence, lobulation, etc.

The same with Grade IIIb

Very high probability

High Suspicious Malignant

IV

8 ~ 30 mm, nodules with spiculation sign or vacuole, vascular convergence, lobulation, etc. which increase the probability of malignancy; Partial solid nodules(solid component > 5 mm)

Surgical resection

Malignancy confirmed by imaging

Malignancy Confirmed by Pathology

V

Malignant disease confirmed by pathology

-

-