Peritoneal Carcinomatosis ICD-10-CM Codes

Read this short guide and learn about peritoneal carcinomatosis ICD codes you can use!

By Priya Singh on Aug 8, 2025.

What peritoneal carcinomatosis ICD codes can I use?

If you're looking for peritoneal carcinomatosis ICD codes, we'd like you to know that the most common choice is C78.6 - Secondary malignant neoplasm of retroperitoneum and peritoneum.

This ICD-10 code is used on a person confirmed to have secondary cancerous tumors in their retroperitoneum and/or peritoneum. Secondary malignant neoplasm is a type of neoplasm that results from treatments like chemotherapy or radiation therapy. It can also be used to refer to cancer that came from somewhere else. Peritoneal Carcinomatosis is one such example. We'll dive into this in the section after the next.

Another code you can use is C7B.04 - Secondary carcinoid tumors of peritoneum. This might be the best choice considering carcinoid is in the name. Just like with secondary malignant neoplasms, secondary carcinoid tumors come from a different source and move to the peritoneum.

Are these peritoneal carcinomatosis ICD code billable?

Yes. These ICD-10 codes are valid and billable.

Clinical information above peritoneal carcinomatosis

Some say that Peritoneal Carcinomatosis is a type of cancer, while some will refer to it as the result of cancer. Either way, this is a condition in which existing cancerous tumors have spread to the peritoneum, a membrane surrounding the abdominal organs. This fits the characteristics of a secondary malignant neoplasm and, by extension, the ICD-10 codes we mentioned earlier.

The peritoneum has several functions. It is a barrier for abdominal organs against pathogens and other invasive particles. It also facilitates blood, lymph, and nerve supply, provides insulation for abdominal organs, lubricates organs inside the peritoneal cavity, and connects several organs.

If a person has peritoneal carcinomatosis, they will likely experience the following symptoms:

They will suddenly lose weight, or they will start to bloat
They will feel nauseated and may start vomiting
They will start feeling fatigued
They might have a hard time breathing
They will feel pain in their abdomen
They will have diarrhea or become constipated
They will start urinating frequently
They will lose their appetite or feel full even when they've only had a few bites to eat

Synonyms include

Carcinoma of peritoneum
Carcinomatosis of peritoneal cavity
Carcinomatosis of peritoneum
Secondary malignant neoplasm of peritoneum
Peritoneum malignant neoplasm due to carcinomatosis
Parietal peritoneum malignant neoplasm due to carcinomatosis
Omentum malignant neoplasm
Mesentery malignant neoplasm
Mesocolon malignant neoplasm
Carcinoma of connective tissues spreading to peritoneum
Abdominal wall cancer spreading to peritoneum

Popular search terms for peritoneal carcinomatosis ICD-10-CM codes

Peritoneal carcinomatosis ICD-10 code
ICD-10 peritoneal carcinomatosis
Peritoneal carcinomatosis diagnosis codes
ICD-10 codes for peritoneal carcinomatosis

Commonly asked questions

Given the carcinomatosis, no. There isn’t. There are no ICD-10 codes with peritoneal carcinomatosis in their name, so the ICD-10 code we indicated is the best choice. There is an ICD-10 code for peritoneum cancer (C48.2), but that’s specific to cancer that starts there. In contrast, carcinomatosis results from a pre-existing cancer that has spread to certain areas, so it doesn’t fit that ICD-10 code.

To diagnose this, healthcare professionals will conduct blood tests, imaging tests, and/or biopsies. They might even detect this while performing surgery for another cancer.

It depends on how severe it is, but if a person has this, the person has a severe enough cancer that gave birth to this problem. Treatment for this can be surgical (cytoreductive surgery or peritonectomy). It can also come in the form of hyperthermic intraperitoneal chemotherapy.

EHR and practice management software

Get started for free

*No credit card required

Start for free

Free

$0/usd

Unlimited clients

Telehealth

1GB of storage

Client portal text

Automated billing and online payments