Metastatic castration-resistant prostate cancer
Metastasis from gastroesophageal adenocarcinoma
Secondary malignant melanoma of skin
Metastatic lymphoepithelial carcinoma
Malignant infantile fibrosarcoma
Complex mixed and stromal malignant neoplasm of endometrium of corpus uteri
Metastatic eccrine porocarcinoma
Tumour invades beyond pancreatic capsule with direct extension to adjacent structures AND/OR organs (endocrine pancreas)
Tumour invasion into adjacent tissues
Neoplasm of unknown origin
Metastatic small cell neuroendocrine carcinoma
Tumour involvement of noncontiguous structures present
Metastatic acantholytic squamous cell carcinoma
Metastatic malignant infantile fibrosarcoma
Metastases
gBRCA-mutated, HER2(-) metastatic breast carcinoma
Cancer metastatic to thyroid
Metastatic rhabdosarcoma
Metastatic well-differentiated neuroendocrine tumor
Malignant tumour involving an organ by direct extension from uterus
Metastatic malignant synovioma
Metastatic hepatocellular carcinoma
Endometrial stromal tumor
Pathologic fracture of bone at site of metastatic neoplasm
Tumour invasion by direct extension from organ of origin to adjacent organ
Metastatic adenosquamous carcinoma
Metastatic spindle cell rhabdomyosarcoma
Metastatic neuroblastoma
Metastatic penile cancer
Metastatic cancer NOS
Malignant tumour of unknown origin
Malignant pachymeningitis
Endometrial stromal tumour
Malignant tumour involving an organ by direct extension from endometrium
Secondary malignant deposit
CA - Secondary cancer
Metastatic malignant neoplasm of thyroid gland
Metastatic glassy cell carcinoma
Metastasis to thyroid
Metastatic superficial spreading melanoma
Secondary cancer
Neoplasm, metastatic (morphologic abnormality)
Tumor involvement of noncontiguous structures present
Infantile fibrosarcoma
Anaplastic thyroid carcinoma
Malignant tumour involving an organ by direct extension from ovary
Metastatic malignant neoplasm to unknown site
Metastatic rhabdomyosarcoma
Secondary malignant neoplasm of thyroid gland
Stage IVb: Haematogenous or lymphatic dissemination (thymus gland)
Neoplasm, secondary
Metastatic embryonal rhabdomyosarcoma
Metastasis from malignant tumor of penis
Metastatic squamous cell carcinoma
Malignant tumour involving an organ by direct extension from prostate
Secondary sebaceous adenocarcinoma
Metastatic malignant neoplasm to thyroid gland
Metastatic sebaceous adenocarcinoma
Metastatic Malignant Neoplasm
Malignant tumour involving an organ by direct extension from uterine cervix
Metastatic extraskeletal osteosarcoma
Human epidermal growth factor 2 positive carcinoma of breast
Metastatic neoplasm
Metastatic fibrosarcoma
Stage 3: Extraglandular extension of tumour without other organ involvement (adrenal cortical carcinoma)
Metastatic spindle cell melanoma
Metastatic cancer
Stage III: Extraglandular extension of tumour without other organ involvement (adrenal cortical carcinoma)
Intergroup rhabdomyosarcoma study post-surgical clinical group IV: Any size primary tumor, with or without regional lymph node involvement, with distant metastases, without respect to surgical approach to primary tumor
Metastatic anaplastic thyroid carcinoma
Intergroup rhabdomyosarcoma study post-surgical clinical group IV: Any size primary tumour, with or without regional lymph node involvement, with distant metastases, without respect to surgical approach to primary tumour
Synovial sarcoma
Metastatic pilomatrix carcinoma
Metastasis - unknown primary
Metastasis from human epidermal growth factor 2 positive carcinoma of breast
Metastatic disease NOS
Secondary adenocarcinoma
Stage III: Macroscopic invasion of neighboring organs (thymus gland)
Stage III: Extraglandular extension of tumor without other organ involvement (adrenal cortical carcinoma)
Metastatic ganglioneuroblastoma
Lymphoedema due to malignant infiltration
Malignant tumour involving an organ by direct extension from bladder
Metastatic balloon cell malignant melanoma
Lymphedema due to malignant infiltration
Tumour metastasis
Metastatic collecting duct carcinoma
Metastatic inflammatory carcinoma
Pleomorphic rhabdomyosarcoma
Pachymeningitis
Lentigo maligna melanoma
Tumour invasion by direct extension to other structures
Embryonal rhabdomyosarcoma
Metastatic synovial sarcoma
Metastatic malignant melanoma with diffuse hypermelanosis
secondary neoplasm
Metastatic liver cell carcinoma
Oligometastatic malignant neoplasm
Pachymeningitis due to secondary malignant neoplastic disease
Malignant synovioma
Metastatic malignant melanoma
Oxyphilic adenocarcinoma
Stage 4: Distant metastasis or extension into other organs (adrenal cortical carcinoma)
Secondary tumor
Metastatic neuroendocrine tumour
Metastatic carcinoma of breast
Metastatic neuroendocrine tumor
Neoplasm, metastatic
Germline BRCA-mutated, HER2-negative metastatic breast cancer
Metastatic malignant neoplasm of unknown site
Metastatic fracture of bone
Metastatic cancer of penis
Tumor invades beyond pancreatic capsule to adjacent structures AND/OR organs (endocrine pancreas)
Malignant tumor - unknown primary
Oligometastatic malignant neoplastic disease
Ganglioneuroblastoma
Tumor metastasis
Malignant tumor involving an organ by direct extension from endometrium
Distant metastasis present
Metastatic neoplasm (disease)
Metastatic spindle cell rhabdosarcoma
Oligometastatic tumour
Spindle cell malignant melanoma
Tumour invades beyond pancreatic capsule to adjacent structures AND/OR organs (endocrine pancreas)
Secondaries
Metastatic urothelial carcinoma
Metastatic human epidermal growth factor 2 positive carcinoma of breast
Metastatic adenocarcinoma
Malignant tumor involving an organ by direct extension from uterus
Metastatic adenocarcinoma of unknown origin
Secondary small cell carcinoma
Metastatic malignant melanoma to skin
Tumour, metastatic
Metastatic disease
Metastatic carcinoma to breast
Metastatic desmoplastic malignant melanoma
Oligometastatic tumor
LMM - Lentigo maligna melanoma
Fibrosarcoma
Malignant tumour - unknown primary
Metastatic oxyphilic adenocarcinoma
Balloon cell malignant melanoma
Stage IV: Distant metastasis or extension into other organs (adrenal cortical carcinoma)
Tumor invasion by direct extension from organ of origin to adjacent organ
Metastatic renal cell carcinoma
Metastatic malignant melanoma of skin
Stage 3: Extraglandular extension of tumor without other organ involvement (adrenal cortical carcinoma)
Metastatic malignant neoplasm (disorder)
Secondary malignant neoplastic disease
Tumor, secondary
Malignant tumour involving an organ by direct extension from vagina
Metastasis from collecting duct carcinoma of nipple
Metastatic malignant glioma
Secondary malignant neoplasm of unknown site
Malignant tumor involving an organ by direct extension from vagina
Malignant tumor involving an organ by direct extension from prostate
Metastatic papillary squamous cell carcinoma
Malignant tumour involving an organ by direct extension from fallopian tube
Tumor invasion into adjacent tissues
Metastatic pleomorphic rhabdomyosarcoma
Tumor invades beyond pancreatic capsule with direct extension to adjacent structures AND/OR organs (endocrine pancreas)
Intergroup rhabdomyosarcoma study post-surgical clinical group finding
Metastasis from hormone-refractory prostate cancer
Metastatic lobular carcinoma
Metastasis from pancreatic endocrine carcinoma
Tumour of unknown origin
Metastatic lentigo maligna melanoma
Malignant tumor involving an organ by direct extension from bladder
Malignant tumor involving an organ by direct extension from uterine cervix
Oligometastatic secondary malignant neoplasm
Spindle cell rhabdomyosarcoma
Metastatic cholangiocarcinoma
Human epidermal growth factor 2 (HER2) negative carcinoma of breast
Metastatic well-differentiated neuroendocrine tumour
Secondary tumour
Oligometastatic disease
Metastatic hormone refractory prostate cancer
HER2 positive metastatic breast cancer
Metastatic apocrine adenocarcinoma
Tumour, secondary
HER2-positive carcinoma of breast
Stage IVb: Hematogenous or lymphatic dissemination (thymus gland)
Tumor of unknown origin
Metastatic endometrial stromal sarcoma
Metastatic myxofibrosarcoma
Metastatic malignant disease
Secondary carcinoma of breast
Malignant tumor involving an organ by direct extension from fallopian tube
Metastatic transitional cell carcinoma of urinary tract
Metastatic small cell carcinoma
Metastatic infantile fibrosarcoma
Metastatic germinoma
Metastatic pancreatic endocrine carcinoma
Metastatic gastroesophageal adenocarcinoma
Tumor invasion by direct extension to other structures
Germline BRCA-mutated human epidermal growth factor receptor 2 negative metastatic carcinoma of breast
Malignant neoplasm of unknown origin
Cancer - unknown origin
Malignant tumor involving an organ by direct extension from ovary
Malignant tumor of unknown origin
Metastatic clear cell renal cell carcinoma
Thymic epithelial neoplasm stage finding
Human epidermal growth factor 2 negative carcinoma of breast
Tumor, metastatic

Frequently Asked Questions

What is the ICD-10 code for secondary malignant neoplasm of unspecified site?

The ICD-10-CM code for secondary malignant neoplasm of unspecified site is C79.9. The full clinical description is "Secondary malignant neoplasm of unspecified site". C79.9 is a billable/specific code that can be used on insurance claims and medical billing.

What does ICD-10 code C79.9 mean?

ICD-10-CM code C79.9 represents “Secondary malignant neoplasm of unspecified site”. It is classified under Chapter 2: Neoplasms and is a billable/specific code that can be used on a claim.

Is C79.9 a billable code?

Yes, C79.9 is a billable/specific ICD-10-CM code and can be used to indicate a diagnosis on a medical claim.

What chapter is C79.9 in?

C79.9 is in Chapter 2: Neoplasms (codes C00-D49).

What codes cannot be used with C79.9?

C79.9 has Excludes1 notes indicating codes that cannot be used together with it, including: secondary carcinoid tumors (C7B.-); secondary neuroendocrine tumors (C7B.-); carcinomatosis NOS (C80.0); and 2 more.

What SNOMED CT codes does C79.9 map to?

C79.9 maps to 99 SNOMED CT concepts: 255031003, 403922007, 128462008, 255052006, 94634005, and 94 more. SNOMED CT is a clinical terminology used in electronic health records.

What are the UMLS CUIs for C79.9?

C79.9 is linked to 2 UMLS Concept Unique Identifiers: C2939419, C2845974. The UMLS (Unified Medical Language System) integrates multiple biomedical vocabularies maintained by the U.S. National Library of Medicine.

How does C79.9 relate to ICF functioning codes?

ICF (International Classification of Functioning, Disability and Health) codes describe how conditions like secondary malignant neoplasm of unspecified site affect a person's functioning — body functions, activities, participation, and environmental factors. AutoICD provides ICF Core Sets for 12+ conditions and can map clinical text to ICF categories automatically. Browse the ICF directory to explore functioning codes.

What is the ICD-11 equivalent of C79.9?

C79.9 maps to the ICD-11 code: 2E2Z (Malignant neoplasm metastasis, unspecified).

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Includes SNOMED Clinical Terms® (SNOMED CT®) used by permission of SNOMED International. Includes content from the UMLS Metathesaurus, courtesy of the U.S. National Library of Medicine.