Bosniak

classification of cystic renal masses, version 2019

Classification of cystic renal masses into classes by likelihood of malignancy.

vigenteRadiology consensus (Silverman et al.)2019CT, MRI

IClass I IIClass II IIFClass IIF IIIClass III IVClass IV

Aplicar o Bosniak a um achado

Descreva o achado como no laudo. A resposta aponta uma das categorias publicadas, com a probabilidade e o trecho que a decide.

Categorias

Reescritas a partir da fonte e citadas

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Class I

Well-defined cystic mass with a thin (2 mm or less) smooth wall that may enhance; homogeneous simple-fluid attenuation (about -9 to 20 HU on CT); no septa, no calcification, and no nodules.

CondutaNo imaging follow-up indicated; may be described simply as a cyst.

RiscoConsidered universally benign (essentially 0% malignancy).

verificadoBosniak Classification of Cystic Renal Masses, Version 2019: An Update Proposal and Needs AssessmentSilverman et al., Radiology 2019 (PMC6677285), CT/MRI criteria Table 2; corroborated radiologyassistant.nl Bozniak-2019 section 'Bosniak I'

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Class II

Cystic masses with a thin (2 mm or less) smooth wall and few (1-3) thin (2 mm or less) septa, where wall and septa may enhance and calcification of any type is allowed; also includes several homogeneous categories such as masses about -9 to 20 HU, homogeneous hyperattenuating masses 70 HU or greater at noncontrast CT, homogeneous nonenhancing masses above 20 HU at renal-mass-protocol CT, and homogeneous masses about 21-30 HU at portal venous phase.

CondutaNo follow-up indicated for typical cases; treated as benign.

RiscoReported malignancy rate is below 1% (may be as low as 0%).

IIF

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Class IIF

Cystic masses with a smooth, minimally thickened (3 mm) enhancing wall, or smooth minimal (3 mm) thickening of one or more enhancing septa, or many (4 or more) smooth thin (2 mm or less) enhancing septa.

CondutaImaging surveillance (follow-up) is recommended; observation is considered safe over a roughly 5-year period.

RiscoReported malignancy rates are wide, in the range of 0% to 38%; the article notes that of 954 stable IIF masses only 54 were resected, of which 9 (about 17%) were malignant, while about 94% (900 of 954) were not resected and did not progress.

verificadoBosniak Classification of Cystic Renal Masses, Version 2019: An Update Proposal and Needs AssessmentSilverman et al., Radiology 2019 (PMC6677285), CT/MRI criteria Table 2 and accompanying note; corroborated radiologyassistant.nl Bozniak-2019 section 'Bosniak IIF'

III

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Class III

Cystic masses with one or more enhancing thick (4 mm or greater in width) or enhancing irregular (3 mm or smaller obtusely-margined convex protrusions) walls or septa.

CondutaManagement varies between institutions, with resection/ablation historically standard and active surveillance increasingly advocated; choice depends on lesion size, patient comorbidities, and surgeon preference.

RiscoIndeterminate; approximately half of resected Bosniak III masses are malignant, with individual series ranging from about 25% to 100% (conversely about half are benign).

verificadoBosniak Classification of Cystic Renal Masses, Version 2019: An Update Proposal and Needs AssessmentSilverman et al., Radiology 2019 (PMC6677285), CT/MRI criteria Table 2; irregular definition Table 3; corroborated radiologyassistant.nl Bozniak-2019 section 'Bosniak III'

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Class IV

Cystic masses with one or more enhancing nodules, defined as a focal enhancing convex protrusion of any size with acute margins, or a 4 mm or larger convex protrusion with obtuse margins relative to the wall or a septum.

CondutaTreatment (resection or ablation) is recommended in most cases when patient characteristics allow; observation is discussed only for selected patients.

RiscoApproximately 90% malignant, with individual series ranging from about 56% to 100% (a minority are benign).

verificadoBosniak Classification of Cystic Renal Masses, Version 2019: An Update Proposal and Needs AssessmentSilverman et al., Radiology 2019 (PMC6677285), CT/MRI criteria Table 2; nodule definition Table 3; corroborated radiologyassistant.nl Bozniak-2019 section 'Bosniak IV'

Lógica de decisão estruturada

{
  "categories": [
    "I",
    "II",
    "IIF",
    "III",
    "IV"
  ]
}

Referência, não é dispositivo médico. Confira a publicação primária vigente. O radiologista que assina o laudo continua autor e responsável.