December 2022 Revision History for the Solid Tumor Rules

• “What You Need to Know About the Solid Tumor Rules” section
  • Added: “Other Sites was updated for 2023. The Solid Tumor General Instructions apply to sites covered in Other for cases diagnosed January 1, 2023 and forward.”
• “SUBMITTING QUESTIONS” section
  • Added: “IMPORTANT INFORMATION: When needed, we will consult with experts to provide guidance and clarifications when answering difficult or unusual questions. Our specialty matter experts (SMEs) are authors of WHO Classification of Tumors books, CAP pathologists, and recognized experts in their fields of interest.”
• “General Equivalent or Equal Terms” section
  • Added: “No evidence of disease; NED; disease free”
• “How to Use the Solid Tumor Rules”
  • “Other Sites” information added to this section: “A primary using Other Sites MPH rules diagnosed before 1/1/2023 and a subsequent primary also covered in Other Sites diagnosed 1/1/2023 or later: Use the 2023 Other Sites Rules”
• “Multiple Primary Rules Do NOT Apply to Tumors Described as Metastases” Section
  • Example Added
• “Timing Rules” section
  • Added: “Once a patient has been diagnosed with metastatic disease, whether at diagnosis or later, they will never be NED.”

Terms and Definitions

• New Section: New for 2023
• Table 2: Histology Combination Codes
  • Duct + Lobular row
    • 8519 (Pleomorphic lobular carcinoma) added
    • Note 1 deleted: Both histologies, duct and lobular, must have the same behavior code.
    • “Additional Combinations of duct and lobular” section added
• Table 3: Specific Histologies, NOS, and Subtypes/Variants
  • Carcinoma NST 8500 row
    • Clarification: “Cribriform carcinoma in situ 8201/2” added to the subtypes/variants
  • Papillary Carcinoma row
    • Clarification: “Encapsulated papillary carcinoma” and “non-infiltrating/intracystic” combined into the same line 8504/2
  • Sarcoma row
    • “Post radiation angiosarcoma of breast” added as a synonym of angiosarcoma
    • Note 3 added regarding angiosarcoma synonyms

Multiple Primary Rules

• M Rule: Abstract multiple primaries when the patient has a subsequent tumor after being clinically disease-free for greater than five years…
  • Note 6 added: “When a breast resection was done and a subsequent tumor is identified in the remaining chest wall, muscle, or skin AND there was no residual breast tissue identified in the resected specimen, this is a recurrence and not a new primary.”
• M Rule: Abstract a single primary when there are multiple tumors of carcinoma NST/duct and lobular
  • Behavior requirement removed
  • Note 3: “Lobular carcinoma includes…” added the following bullet:
    • Invasive pleomorphic lobular carcinoma 8520/3
  • Note 4 added: “When a mixture of behaviors is present in carcinoma, NST and lobular carcinoma, follow the H rules to determine the correct histology code.”

Histology Coding Rules

• H Rule: Code DCIS and in situ lobular carcinoma 8522/2 when DCIS and in situ lobular carcinoma are present
  • Note 3 added: “8522/2 includes DCIS and pleomorphic lobular carcinoma in situ.”
• H Rule: Code the invasive histology when both invasive and in situ components are present
  • Note 2 added: “The following histologies are exceptions to this rule. When a single tumor has one of the histologies listed, continue through the rules.
    • Encapsulated papillary carcinoma with invasion/with invasive carcinoma, NST/invasive duct carcinoma
    • Solid papillary carcinoma with invasion”
  • Note 3 added: “When a single tumor has carcinoma NST/duct and lobular with different behaviors, continue through the rules.”
• H Rule: Code duct carcinoma and lobular carcinoma 8522/3 when the final diagnosis is any of the following…
  • Rule rewritten and clarified
  • Note 1 added: “Assign behavior code /3 even when an in situ histology is mixed with an invasive. This aligns with ICD-O-3.2 and was vetted with specialty matter experts.”
• H Rule: Code the invasive histology when there are both invasive and in situ histologies
  • Examples deleted
  • Exception added: “Continue through the rules when there are multiple tumors of ductal and lobular carcinoma with different behaviors.”
• H Rule: Code 8522 when carcinoma NST and lobular are present in multiple tumors.
  • Rule rewritten and clarified
  • Note 1 added: “Assign behavior code /3 even when an in situ histology is mixed with an invasive. This aligns with ICD-O-3.2 and was vetted with specialty matter experts.”
  • Note 4 modified: “This combination code specifically identifies carcinoma NST and lobular carcinoma. For all other histological combinations, continue through the rules.

Terms and Definitions

• Table 1: Specific Histologies, NOS, and Subtypes/Variants
  • GIST 8936 row: Synonyms added:
    • Gastrointestinal autonomic nerve tumor
    • GANT
    • Gastrointestinal pacemaker cell tumor
  • Row added: Mixed neuroendocrine non-neuroendocrine neoplasm 8154 (MiNEN)

• C754 and C755 added to the H&N module

Terms and Definitions

• Table 1: Tumors of Nasal Cavity, Paranasal Sinuses and Skull base
  • Malignant peripheral nerve sheath tumor 9540/3 row
    • Subtype/variant added: “Malignant neurilemoma/malignant schwannoma 9560/3”
  • Olfactory neuroblastoma 9522/3 row
    • Subtypes/variants added:
      • “Esthesioneurocytoma 9521/3”
      • “Esthesioneuroepithelioma/Olfactory neuroepithelioma 9523/3”
• Table 4: Tumors of Oral Cavity and Mobile Tongue
  • Squamous Cell Carcinoma 8070 Row
    • Subtype/variant added: “Verrucous squamous cell carcinoma 8051”
• Table 9: Paraganglioma of Carotid Body, Larynx, Middle Ear, Vagal Nerve
  • Table updated for readability
  • C754, C755 added

Multiple Primary Rules

• M Rule: Abstract multiple primaries when the patient has a subsequent tumor after being clinically disease-free for greater than five years after the original diagnosis or last recurrence.
  • Note added: “When the patient has more than one Head & Neck primary, it is often difficult to determine which primary recurred. Use the last date of recurrence for any tumor to calculate the time interval.”

Histology Coding Rules

• H Rule: Code the histology when only one histology is present.
  • Note 3 clarified: “Cases diagnosed prior to 1/1/2021: Squamous cell carcinoma, HPV positive (8085) and squamous cell carcinoma, HPV negative (8086) are coded only when HPV status is determined by tests based on ISH, PCR, RT-PCR technologies to detect the viral DNA or RNA. p16 is not a valid test to assign these histology codes.”
  • Note 4 added: “Cases diagnosed 1/1/2021 forward: p16 test results can be used to code squamous cell carcinoma, HPV positive (8085) and squamous cell carcinoma, HPV negative (8086).”

Terms and Definitions

• Equivalent or Equal Terms
  • Added to Carcinoma; adenocarcinoma bullet
    • “A histology type must be stated for these terms to be equal”
    • “Example: Renal cell carcinoma and renal cell adenocarcinoma are both coded 8312”
• Terms that are NOT Equivalent or Equal
  • Added: “Carcinoma, NOS 8010 is not equivalent to adenocarcinoma, NOS 8140”
• Table 1: Specific Histologies, NOS, and Subtypes/Variants
  • Renal cell carcinoma 8312 row
    • Added “Note 4: “Oncocytic” indicates cells that have abundant eosinophilic cytoplasm due to the accumulation of mitochondria and is not a histologic type unless listed in column 3.”
    • Added “Note 5: Beginning with cases diagnosed 1/1/2022 forward, SDHD is coded 8311/3. Cases diagnosed prior to 1/1/2022 should be coded 8312.”
    • Added as synonyms:
      • Eosinophilic renal cell carcinoma
      • Oncocytic renal cell carcinoma
    • “Hybrid oncocytic chromophobe tumor” added as synonym for 8317

Multiple Primary Rules

• M Rule: Abstract multiple primaries when separate/non-contiguous tumors are two or more different subtypes/variants…
  • Note 2 bullets consolidated and made clearer

Terms and Definitions

• Equivalent or Equal Terms
  • Added to Carcinoma; adenocarcinoma bullet
    • “A histology type must be stated for these terms to be equal”
    • “Example: Acinar carcinoma and acinar adenocarcinoma are both coded 8551”
• Terms that are NOT Equivalent or Equal
  • Added: “Carcinoma, NOS 8010 is not equivalent to adenocarcinoma, NOS 8140”
• Table 1: Coding Primary Site
  • “Infrahilar NOS” added to Lung NOS C349 row
• Table 2: Combination/Mixed Histology Codes
  • Adenosquamous carcinoma 8560 row: Note updated with instructions for pre-2023 and 2023+ cases
• Table 3: Specific Histologies, NOS, and Subtype/Variants
  • Adenocarcinoma 8140 row
    • “Invasive non-mucinous adenocarcinoma 8140/3” added as synonym
  • Mucoepidermoid carcinoma 8430 row
    • Note updated: “As of 1/1/2023, mucoepidermoid tumor is no longer a synonym of mucoepidermoid carcinoma in WHO”
  • PEComa malignant 8714/3 row
    • Synonyms added:
      • PEComa of the lung
      • PEComa, malignant
  • Small cell carcinoma 8041/3 row
    • “Neuroendocrine carcinoma, NOS” removed from beneath Typical Carcinoid 8240/3 and added as its own subtype/variant with the code 8246/3
  • Rows added:
    • Carcinosarcoma 8980/3
    • Diffuse pulmonary lymphangiomatosis 9170/3
    • Hyalinizing clear cell carcinoma 8310
    • Lymphoangioleiomyomatosis 9174/3
    • Pleuropulmonary blastoma 8973/3
    • Pulmonary blastoma 8972/3
    • Thoracic SMARCA4-deficient undifferentiated tumor 8044/3

Terms and Definitions

• Introduction: Bullet added to Note 6
  • “IMPORTANT FOR 2023 FORWARD: Beginning 1/1/2023, all cases diagnosed with pilocytic astrocytoma/juvenile pilocytic astrocytoma and new related terminology are to be reported with behavior /1. They will no longer be collected with malignant behavior (/3). See the Non-malignant CNS Rules.”
• New for 2023: Information regarding pilocytic astrocytoma/juvenile astrocytoma reportability added
• Table 3: Specific Histologies, NOS, and Subtypes/Variants
  • Astroblastoma 9430 row
    • Synonym added: “Astroblastoma, MN1-altered”
  • Astrocytoma NOS 9400 row
    • Synonym added: “Astrocytoma, IDH-mutant, grade 2”
    • Subtype/variants added:
      • “Astrocytoma, IDH-mutant, grade 3 9401”
      • “Astrocytoma, IDH-mutant, grade 4 9445”
    • CNS ganglioneuroblastoma 9490 row
      • “NEC/NOS” added to CNS embryonal tumor 9473
    • CNS neuroblastoma 9500 row
      • Synonyms added:
        • CAN neuroblastoma, FOXR2-activated
        • CNS Tumor with BCCR internal tandem duplication
      • Diffuse midline glioma H3 K27M mutant 9385 row
        • Synonyms added:
          • Diffuse intrinsic pontine glioma
          • Diffuse hemispheric glioma, H3 G34-mutant
          • Diffuse pediatric-type high grade glioma, H3-wildtype and IDH-wildtype
          • DIPG
          • Infant-type hemispheric glioma
      • Ependymoma 9391 row
        • Synonyms added:
          • Posterior fossa ependymoma, NOS
          • Spinal ependymoma, NOS
          • Supratentorial ependymoma, NOS
        • Synonyms added for Ependymoma, RELA fusion-positive 9396* (Note also added)
      • Malignant peripheral nerve sheath tumor 9540 row
        • Synonym added: Malignant melanotic nerve sheath tumor
      • Medulloblastoma NOS 9470 row
        • Synonym added: Medulloblastoma, histologically defined
      • Oligodendroglioma NOS 9450 row
        • “Grade 2” added to the synonym “Oligodendroglioma IDH-mutant and 1p/19q-codeleted, grade 2”
        • Synonym added for 9451: “Oligodendroglioma, IDH-mutant and 1p/19q-codeleted, grade 3”
      • Pilocytic astrocytoma 9421 row
        • Note 1 updated for cases diagnosed prior to 2023
        • Note 2 added: “Beginning with cases diagnosed 1/1/2023 forward, pilocytic astrocytoma will no longer be reported with /3 behavior. Pilocytic astrocytoma and the related terms listed below are to be reported as a /1
          • Diffuse astrocytoma, MTB- or MYBL1-alterd
          • Diffuse low-grade glioma, MAPK pathway- altered+”
      • Sarcoma NOS 8800 row
        • Subtype/variant added: “Primary intracranial sarcoma, DICER1-mutant 9480”
      • Rows added
        • Diffuse leptomeningeal glioneuronal tumor 9509
        • High-grade astrocytoma with piloid features 9421/3
        • Neuroepithelial tumor, malignant 8000/3
        • Pituitary adenoma/pituitary neuroendocrine tumor 8272/3

Histology Coding Rules

• New H Rule: Code single tumors with two variants as follows…

Terms and Definitions

• Introduction: Note 5: pilocytic astrocytoma/juvenile astrocytoma reportability updated
• New for 2023: Information regarding pilocytic astrocytoma/juvenile astrocytoma reportability added
• “Reportability Criteria for Non-Malignant CNS Neoplasms” section
  • List item added: Diagnostic imaging definitively states the tumor as non-malignant (/0 or/1) OR
• Table 5: Histologic Types of Non-Malignant Intracranial (Brain and Glands) Tumors
  • New row added: Juvenile xanthogranuloma 9749/1 (Intraventricular C715)
• Table 6: Specific Histologies, NOS, and Subtypes/Variants
  • New rows added:
    • Diffuse astrocytoma, MYB- or MYBL1 altered 9421/1
    • Juvenile xanthogranuloma 9749/1
    • Multinodular and vacuolating neuronal tumor 9509/0
    • Neuroepithelial tumor, benign 8000/0
    • Papillary glioneuronal tumor 9509/1
    • Polymorphous low-grade neuroepithelial tumor of the young 9413/0
  • Desmoplastic infantile astrocytoma and ganglioglioma 9412/1 row
    • New synonym added: DIAG
  • Dysembryoplastic neuroepithelial tumor 9413/0 row
    • Note added: “DNET and PLNTY have the same ICD-O code but are distinctly different histologies. Because they are different, they are on separate rows in column 1”
    • Synonym changed from DNT to DNET
  • Osteoma 9180/0 row removed
  • Papillary glioneuronal tumor 9509/1
    • Notes added
      • Note 1: MVNT and papillary glioneuronal tumor have the same ICD-O code but are distinctly different histologies based on behavior codes. Because they are different, they are on rows in column 1.
      • Note 2: Beginning with cases diagnosed 1/1/2023 forward, leptomeningeal glioneuronal tumor is coded 9509/3. See the Malignant CNS rules.
  • Schwannoma 9560/0 row
    • Synonym added: Acoustic neuroma

Terms and Definitions

• Equivalent or Equal Terms
  • Removed: Carcinoma; adenocarcinoma
• Terms that are Note Equivalent or Equal
  • Terms added: “Carcinoma, NOS (8010) and adenocarcinoma, NOS (8140) are not equivalent”
• Table 2: Specific Histologies, NOS, and Subtypes/Variants
  • Urothelial Carcinoma 8120 row
    • Note 3 added: “The histology term is exactly Plasmacytoid/signet ring cell/diffuse variant. All three terms are used together to indicate a specific variant (coded 8082/3).”

Multiple Primary Rules

• M Rule: Abstract multiple primaries when the patient has a subsequent tumor after being clinically disease-free for greater than three years…
  • Note 1 updated to clarify histology exclusions