# Fleischner — Fleischner Society 2017 pulmonary nodule guidelines

> Management recommendations for incidentally detected pulmonary nodules on CT, organized by nodule type (solid, subsolid) and size, for patients 35 and older without known cancer or immunosuppression.

**Situação:** vigente · **Órgão:** Tórax · **Órgão emissor:** Fleischner Society · **Versão:** 2017 · **Ano:** 2017

## Procedência e vigência
- Família: algoritmo
- Tipo de lógica: matrix
- Modalidade: CT
- Fonte primária: MacMahon H, Naidich DP, Goo JM, et al.. Guidelines for Management of Incidental Pulmonary Nodules Detected on CT Images: From the Fleischner Society 2017 (2017) — https://doi.org/10.1148/radiol.2017161659
- Última verificação: 2026-07-24
- Última checagem: 2026-08-12

## Lógica de decisão
Use the matching outcome_code for cited management and risk text. Do not apply this incidental-nodule algorithm to screening CT, known primary cancer, or immunosuppression.

## Categorias

| Código | Rótulo | Critérios | Conduta | Risco | Localizador | Verificado |
| --- | --- | --- | --- | --- | --- | --- |
| solid-single-<6 | Solid single nodule, under 6 mm | Single solid nodule under 6 mm (under ~100 mm3); recommendation differs by patient risk. | Low risk: no routine follow-up. High risk: optional CT at 12 months. The guideline notes that nodules under 6 mm generally need no routine follow-up, but selected high-risk patients with suspicious morphology and/or upper-lobe location may warrant a 12-month follow-up. | Average malignancy risk is under 1% even in high-risk patients; suspicious morphology and/or upper-lobe location can raise the estimated risk into the 1%-5% range. | Fleischner 2017 Table 1, Section A (Solid Nodules), Single, <6 mm row | ✓ |
| solid-single-6to8 | Solid single nodule, 6 to 8 mm | Single solid noncalcified nodule with mean diameter 6-8 mm (approximately 100-250 mm3); follow-up intensity depends on clinical risk and morphology. | Low risk: CT at 6-12 months, then consider CT at 18-24 months if morphology is suspicious or stability is uncertain. High risk: CT at 6-12 months and again at 18-24 months. | The guideline estimates an average malignancy risk of approximately 0.5%-2.0% for solitary solid nodules in this size band; individual risk varies with morphology and patient factors. | Fleischner 2017 Table 1, Section A (Solid Nodules), Single, 6-8 mm row | ✓ |
| solid-single->8 | Solid single nodule, over 8 mm | Single solid nodule larger than 8 mm (over ~250 mm3); same management for low and high risk. | Consider CT at 3 months, PET/CT, or tissue sampling (applies to both low- and high-risk single nodules). | The guideline cites an average malignancy risk of approximately 3% for an 8-mm solitary nodule, while emphasizing that risk may be substantially higher according to size, morphology, location, and clinical factors. | Fleischner 2017 Table 1, Section A (Solid Nodules), Single, >8 mm row | ✓ |
| solid-multiple-<6 | Solid multiple nodules, under 6 mm | Multiple solid nodules with the largest under 6 mm; recommendation differs by patient risk. Use the most suspicious nodule to guide management. | Low risk: no routine follow-up. High risk: optional CT at 12 months. | Most multiple solid nodules under 6 mm are benign healed granulomas or intrapulmonary lymph nodes; the guideline does not publish a per-row malignancy probability. | Fleischner 2017 Table 1, Section A (Solid Nodules), Multiple, <6 mm row | ✓ |
| solid-multiple->=6 | Solid multiple nodules, 6 mm or larger | Multiple solid nodules with at least one in the 6-8 mm or >8 mm band. Use the most suspicious nodule to guide management; intervals may vary with size and risk. | CT at 3-6 months. At 18-24 months, CT is optional for low-risk patients and recommended for high-risk patients. If one nodule is larger or more suspicious, use its corresponding solitary-nodule pathway to guide management. | No per-row malignancy percentage is given. The most suspicious nodule, which may not be the largest, drives risk assessment; multiplicity and the distribution and morphology of all nodules remain clinically relevant. | Fleischner 2017 Table 1, Section A (Solid Nodules), Multiple, 6-8 mm and >8 mm columns | ✓ |
| ggn-single-<6 | Ground glass single nodule, under 6 mm | Single pure ground-glass nodule under 6 mm. | No routine follow-up. In selected patients with a nodule close to 6 mm, suspicious morphology, or other risk factors, optional CT at approximately 2 and 4 years may be considered. | The guideline cites data in which up to 10% of these nodules grew and nearly 1% progressed to adenocarcinoma over many years, supporting conservative management for most patients. | Fleischner 2017 Table 1, Section B (Subsolid Nodules), Single, Ground glass, <6 mm column | ✓ |
| ggn-single->=6 | Ground glass single nodule, 6 mm or larger | Single pure ground-glass nodule 6 mm or larger. | CT at 6-12 months to confirm persistence, then CT every 2 years out to 5 years. If a solid component or growth develops, consider resection. | Persistent pure ground-glass nodules can represent indolent adenocarcinoma-spectrum lesions; the guideline notes that growth commonly requires 3-4 years to establish and does not provide a single per-row malignancy percentage. | Fleischner 2017 Table 1, Section B (Subsolid Nodules), Single, Ground glass, >=6 mm column | ✓ |
| partsolid-single-<6 | Part solid single nodule, under 6 mm | Single apparent part-solid nodule under 6 mm. A discrete solid component cannot be measured reliably at this size, so the guideline treats it like a pure ground-glass nodule of the same size. | No routine follow-up. Optional longer-term CT may be considered in selected patients when the nodule is close to 6 mm or has suspicious morphology or other risk factors. | The guideline does not publish a separate malignancy probability for apparent part-solid nodules under 6 mm because a true solid component is not reliably defined at this size. | MacMahon et al. 2017, Recommendation 4 (solitary part-solid nodules), first paragraph; Table 1 Section B, <6 mm column | ✓ |
| partsolid-single->=6 | Part solid single nodule, 6 mm or larger | Single part-solid nodule 6 mm or larger. The guideline notes part-solid nodules are generally not defined as such below 6 mm, and persistent part-solid nodules with a solid component of 6 mm or more should be regarded as highly suspicious. | CT at 3-6 months to confirm persistence. If unchanged and the solid component stays under 6 mm, annual CT for at least 5 years. If the solid component is 6 mm or larger, grows, exceeds 8 mm, or morphology is particularly suspicious, consider PET/CT, biopsy, or resection. | Part-solid nodules have a high likelihood of malignancy. A persistent solid component under 6 mm more often represents adenocarcinoma in situ or minimally invasive adenocarcinoma; a component 6 mm or larger is highly suspicious for invasive disease. | Fleischner 2017 Table 1, Section B (Subsolid Nodules), Single, Part solid, >=6 mm column | ✓ |
| subsolid-multiple | Multiple subsolid nodules | Multiple subsolid nodules (ground-glass and/or part-solid). Multiple sub-6 mm pure ground-glass nodules are usually benign. | Under 6 mm: CT at 3-6 months; if stable, consider CT at 2 and 4 years. 6 mm or larger: CT at 3-6 months, with subsequent management based on the most suspicious nodule(s). | Multiple tiny subsolid nodules may be infectious or inflammatory. If persistent, they may represent atypical adenomatous hyperplasia or adenocarcinoma in situ; when at least one lesion is 6 mm or larger, more than one suspicious lesion increases the overall likelihood of cancer. | Fleischner 2017 Table 1, Section B (Subsolid Nodules), Multiple row | ✓ |

### Citações por categoria
- **solid-single-<6**: MacMahon H, Naidich DP, Goo JM, et al.. Guidelines for Management of Incidental Pulmonary Nodules Detected on CT Images: From the Fleischner Society 2017 (2017) — https://doi.org/10.1148/radiol.2017161659 · Fleischner 2017 Table 1, Section A (Solid Nodules), Single, <6 mm row
- **solid-single-6to8**: MacMahon H, Naidich DP, Goo JM, et al.. Guidelines for Management of Incidental Pulmonary Nodules Detected on CT Images: From the Fleischner Society 2017 (2017) — https://doi.org/10.1148/radiol.2017161659 · Fleischner 2017 Table 1, Section A (Solid Nodules), Single, 6-8 mm row
- **solid-single->8**: MacMahon H, Naidich DP, Goo JM, et al.. Guidelines for Management of Incidental Pulmonary Nodules Detected on CT Images: From the Fleischner Society 2017 (2017) — https://doi.org/10.1148/radiol.2017161659 · Fleischner 2017 Table 1, Section A (Solid Nodules), Single, >8 mm row
- **solid-multiple-<6**: MacMahon H, Naidich DP, Goo JM, et al.. Guidelines for Management of Incidental Pulmonary Nodules Detected on CT Images: From the Fleischner Society 2017 (2017) — https://doi.org/10.1148/radiol.2017161659 · Fleischner 2017 Table 1, Section A (Solid Nodules), Multiple, <6 mm row
- **solid-multiple->=6**: MacMahon H, Naidich DP, Goo JM, et al.. Guidelines for Management of Incidental Pulmonary Nodules Detected on CT Images: From the Fleischner Society 2017 (2017) — https://doi.org/10.1148/radiol.2017161659 · Fleischner 2017 Table 1, Section A (Solid Nodules), Multiple, 6-8 mm and >8 mm columns
- **ggn-single-<6**: MacMahon H, Naidich DP, Goo JM, et al.. Guidelines for Management of Incidental Pulmonary Nodules Detected on CT Images: From the Fleischner Society 2017 (2017) — https://doi.org/10.1148/radiol.2017161659 · Fleischner 2017 Table 1, Section B (Subsolid Nodules), Single, Ground glass, <6 mm column
- **ggn-single->=6**: MacMahon H, Naidich DP, Goo JM, et al.. Guidelines for Management of Incidental Pulmonary Nodules Detected on CT Images: From the Fleischner Society 2017 (2017) — https://doi.org/10.1148/radiol.2017161659 · Fleischner 2017 Table 1, Section B (Subsolid Nodules), Single, Ground glass, >=6 mm column
- **partsolid-single-<6**: MacMahon H, Naidich DP, Goo JM, et al.. Guidelines for Management of Incidental Pulmonary Nodules Detected on CT Images: From the Fleischner Society 2017 (2017) — https://doi.org/10.1148/radiol.2017161659 · MacMahon et al. 2017, Recommendation 4 (solitary part-solid nodules), first paragraph; Table 1 Section B, <6 mm column
- **partsolid-single->=6**: MacMahon H, Naidich DP, Goo JM, et al.. Guidelines for Management of Incidental Pulmonary Nodules Detected on CT Images: From the Fleischner Society 2017 (2017) — https://doi.org/10.1148/radiol.2017161659 · Fleischner 2017 Table 1, Section B (Subsolid Nodules), Single, Part solid, >=6 mm column
- **subsolid-multiple**: MacMahon H, Naidich DP, Goo JM, et al.. Guidelines for Management of Incidental Pulmonary Nodules Detected on CT Images: From the Fleischner Society 2017 (2017) — https://doi.org/10.1148/radiol.2017161659 · Fleischner 2017 Table 1, Section B (Subsolid Nodules), Multiple row

## Referências cruzadas
- _fronteira compartilhada_ → [Lung-RADS — Lung CT Screening Reporting and Data System](https://radcommons.laudos.ai/systems/lung-rads-2022.md) — Fleischner governs incidental nodules, Lung-RADS governs screening detected nodules.

## Histórico de versões

| Data | Evento | Detalhe | Situação |
| --- | --- | --- | --- |
| 2017-07-01 | revised | Fleischner Society 2017 guidelines published, updating the 2005 recommendations. | confirmed |


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> Conteúdo de referência reescrito. Confira a publicação primária vigente. Não é dispositivo médico nem substitui o julgamento clínico. O radiologista responsável pelo laudo permanece o autor e o responsável.

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