ICD-9 Code 171.9

Malignant neoplasm of connective and other soft tissue, site unspecified

Not Valid for Submission

171.9 is a legacy non-billable code used to specify a medical diagnosis of malignant neoplasm of connective and other soft tissue, site unspecified. This code was replaced on September 30, 2015 by its ICD-10 equivalent.

ICD-9: 171.9
Short Description:Mal neo soft tissue NOS
Long Description:Malignant neoplasm of connective and other soft tissue, site unspecified

Convert 171.9 to ICD-10

The following crosswalk between ICD-9 to ICD-10 is based based on the General Equivalence Mappings (GEMS) information:

  • C49.9 - Malignant neoplasm of connective and soft tissue, unsp

Code Classification

  • Neoplasms (140–239)
    • Malignant neoplasm of bone, connective tissue, skin, and breast (170-176)
      • 171 Malignant neoplasm of connective and other soft tissue

Information for Medical Professionals


  • Adipocytic liposarcoma
  • Alveolar rhabdomyosarcoma
  • Alveolar soft part sarcoma
  • Angiosarcoma
  • Atypical fibroxanthoma of skin
  • Botryoid rhabdomyosarcoma
  • Carcinoma of bone, connective tissue, skin and breast
  • Cutaneous leiomyosarcoma with granular cell change
  • Dedifferentiated liposarcoma
  • Embryonal rhabdomyosarcoma
  • Epithelioid leiomyosarcoma of skin
  • Epithelioid malignant nerve sheath tumor
  • Ewing's sarcoma of soft tissue
  • Extraskeletal mesenchymal chondrosarcoma
  • Extraskeletal myxoid chondrosarcoma
  • Fibrosarcoma of connective tissue
  • Glandular malignant peripheral nerve sheath tumor
  • Granulocytic sarcoma affecting skin
  • Histiocytic sarcoma
  • Infantile fibrosarcoma
  • Inflammatory malignant fibrous histiocytoma of skin
  • International neuroblastoma pathology classification: Favorable histology group, patient age 1.5 years up to but less than 5 years, with differentiating neuroblastoma
  • International neuroblastoma pathology classification: Favorable histology group, patient less than 1.5 years of age, with poorly differentiated neuroblastoma
  • International neuroblastoma staging system stage 1
  • Intravascular angiosarcoma
  • Leiomyosarcoma
  • Leiomyosarcoma of connective tissue
  • Liposarcoma
  • Liposarcoma of connective tissue
  • Local recurrence of malignant tumor of soft tissue
  • Low-grade fibromyxoid sarcoma
  • Lymphangiosarcoma
  • Malignant fibromatous neoplasm
  • Malignant fibrous histiocytoma
  • Malignant fibrous histiocytoma of skin
  • Malignant granular cell tumor
  • Malignant infiltration of peripheral nerve
  • Malignant infiltration of peripheral nerve plexus
  • Malignant infiltration of soft tissue
  • Malignant lipomatous tumor
  • Malignant melanoma of soft tissues
  • Malignant neoplasm of bone, connective tissue, skin and breast
  • Malignant neoplasm of connective tissue
  • Malignant neoplasm of peripheral nerves and autonomic nervous system
  • Malignant neoplasm of soft tissue
  • Malignant neoplasm of subcutaneous fibrous tissue
  • Malignant peripheral nerve sheath tumor
  • Malignant Triton tumor
  • Malignant tumor of fibrous tissue
  • Malignant tumor of mesothelial tissue
  • Malignant tumor of muscle
  • Malignant tumor of nerve sheath origin
  • Malignant tumor of peripheral nerve
  • Malignant tumor of spinal nerve and sheath
  • Melanotic malignant nerve sheath tumor
  • Metastasis from malignant tumor of soft tissues
  • Metastatic sarcoma
  • Myxoid leiomyosarcoma of skin
  • Myxoid liposarcoma
  • Overlapping malignant neoplasm of soft tissues
  • Pleomorphic liposarcoma
  • Pleomorphic rhabdomyosarcoma
  • Primary leiomyosarcoma
  • Primary malignant neoplasm of blood vessel
  • Primary malignant neoplasm of muscle
  • Primary malignant neoplasm of peripheral nerve
  • Primary malignant neoplasm of peripheral nerves and peripheral autonomic nervous system
  • Primary malignant neoplasm of soft tissues
  • Rhabdomyosarcoma
  • Rhabdomyosarcoma of connective or soft tissue
  • Round cell liposarcoma
  • Sarcoma
  • Sarcoma of bone and connective tissue
  • Sarcoma of connective tissue
  • Sarcoma of soft tissue
  • Sarcomatous metastasis in skin
  • Sclerosing liposarcoma
  • Spindle cell liposarcoma
  • Spindle cell rhabdomyosarcoma
  • Synovial sarcoma
  • Vaccine-induced fibrosarcoma

Index to Diseases and Injuries

References found for the code 171.9 in the Index of Diseases and Injuries:

Information for Patients

Soft Tissue Sarcoma

Your soft tissues connect, support, or surround other tissues. Examples include your muscles, tendons, fat, and blood vessels. Soft tissue sarcoma is a cancer of these soft tissues. There are many kinds, based on the type of tissue they started in. They may cause a lump or swelling in the soft tissue. Sometimes they spread and can press on nerves and organs, causing problems such as pain or trouble breathing.

No one knows exactly what causes these cancers. They are not common, but you have a higher risk if you have been exposed to certain chemicals, have had radiation therapy, or have certain genetic diseases.

Doctors diagnose soft tissue sarcomas with a biopsy. Treatments include surgery to remove the tumor, radiation therapy, chemotherapy, or a combination.

NIH: National Cancer Institute

[Read More]

ICD-9 Footnotes

General Equivalence Map Definitions
The ICD-9 and ICD-10 GEMs are used to facilitate linking between the diagnosis codes in ICD-9-CM and the new ICD-10-CM code set. The GEMs are the raw material from which providers, health information vendors and payers can derive specific applied mappings to meet their needs.

  • Approximate Flag - The approximate flag is on, indicating that the relationship between the code in the source system and the code in the target system is an approximate equivalent.
  • No Map Flag - The no map flag indicates that a code in the source system is not linked to any code in the target system.
  • Combination Flag - The combination flag indicates that more than one code in the target system is required to satisfy the full equivalent meaning of a code in the source system.

Index of Diseases and Injuries Definitions

  • And - The word "and" should be interpreted to mean either "and" or "or" when it appears in a title.
  • Code also note - A "code also" note instructs that two codes may be required to fully describe a condition, but this note does not provide sequencing direction.
  • Code first - Certain conditions have both an underlying etiology and multiple body system manifestations due to the underlying etiology. For such conditions, the ICD-10-CM has a coding convention that requires the underlying condition be sequenced first followed by the manifestation. Wherever such a combination exists, there is a "use additional code" note at the etiology code, and a "code first" note at the manifestation code. These instructional notes indicate the proper sequencing order of the codes, etiology followed by manifestation.
  • Type 1 Excludes Notes - A type 1 Excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
  • Type 2 Excludes Notes - A type 2 Excludes note represents "Not included here". An excludes2 note indicates that the condition excluded is not part of the condition represented by the code, but a patient may have both conditions at the same time. When an Excludes2 note appears under a code, it is acceptable to use both the code and the excluded code together, when appropriate.
  • Includes Notes - This note appears immediately under a three character code title to further define, or give examples of, the content of the category.
  • Inclusion terms - List of terms is included under some codes. These terms are the conditions for which that code is to be used. The terms may be synonyms of the code title, or, in the case of "other specified" codes, the terms are a list of the various conditions assigned to that code. The inclusion terms are not necessarily exhaustive. Additional terms found only in the Alphabetic Index may also be assigned to a code.
  • NEC "Not elsewhere classifiable" - This abbreviation in the Alphabetic Index represents "other specified". When a specific code is not available for a condition, the Alphabetic Index directs the coder to the "other specified” code in the Tabular List.
  • NOS "Not otherwise specified" - This abbreviation is the equivalent of unspecified.
  • See - The "see" instruction following a main term in the Alphabetic Index indicates that another term should be referenced. It is necessary to go to the main term referenced with the "see" note to locate the correct code.
  • See Also - A "see also" instruction following a main term in the Alphabetic Index instructs that there is another main term that may also be referenced that may provide additional Alphabetic Index entries that may be useful. It is not necessary to follow the "see also" note when the original main term provides the necessary code.
  • 7th Characters - Certain ICD-10-CM categories have applicable 7th characters. The applicable 7th character is required for all codes within the category, or as the notes in the Tabular List instruct. The 7th character must always be the 7th character in the data field. If a code that requires a 7th character is not 6 characters, a placeholder X must be used to fill in the empty characters.
  • With - The word "with" should be interpreted to mean "associated with" or "due to" when it appears in a code title, the Alphabetic Index, or an instructional note in the Tabular List. The word "with" in the Alphabetic Index is sequenced immediately following the main term, not in alphabetical order.