# Mucinous cystic neoplasm of the pancreas with associated invasive carcinoma (MCN-associated carcinoma)

Source: https://onco.cc/cancers/mcn-associated-carcinoma/  
OnCo record `mcn-associated-carcinoma` (Cancer). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

MCN-associated carcinoma is pancreatic cancer that has developed inside a mucinous cystic neoplasm, a thick-walled cyst with ovary-like tissue in its wall that occurs almost only in women, usually in the tail of the pancreas. Most such cysts are benign when removed; the minority with invasive cancer are larger, carry nodules and occur in older women, and about six in ten survive five years.

## Summary

What it is. A mucinous cystic neoplasm is defined by ovarian-type stroma in the cyst wall and by the absence of communication with the pancreatic duct; the 2019 WHO classification grades it as MCN with low- or high-grade dysplasia or MCN with associated invasive carcinoma (Nagtegaal 2020). The invasive component is usually a tubular ductal adenocarcinoma and occasionally colloid or undifferentiated with osteoclast-like giant cells (Adsay 2001; Muraki 2016).

How it differs from its parent. In 163 resected MCNs defined by ovarian stroma, 95 percent were in women and 97 percent in the distal pancreas; 72 percent were adenomas, 10.5 percent borderline, 5.5 percent carcinoma in situ and 12 percent invasive carcinoma; patients with invasive cancer were older (55 against 44 years); every cancer was 40 mm or larger or had nodules; five-year disease-specific survival was 100 percent for non-invasive and 57 percent for invasive MCNs, and only invasive tumours recurred (Crippa 2008). In 156 Japanese cases, 82.7 percent were adenomas, 13.4 percent non-invasive carcinomas and 3.9 percent invasive; 98.1 percent were women with a mean age of 48, mean size 65 mm, and five- and ten-year survival were 96.6 percent overall, with cyst diameter and mural nodules predicting malignancy (Yamao 2011).

How common it is. Not counted by registries; the shares above come from resected series and understate benign cysts that were never removed.

How it is treated. Because MCNs sit in the body and tail, the operation is usually a distal pancreatectomy with splenectomy, minimally invasive where the DIPLOMA trial has shown the oncological outcome is not inferior for pancreatic cancer (Korrel 2023). Non-invasive MCNs are cured by resection and need no follow-up in the European guidance cited on the parent cyst page; MCN with invasive carcinoma is staged and treated as pancreatic ductal adenocarcinoma with adjuvant chemotherapy. The Japanese series recommended resecting all MCNs, while European guidance allows observation of small MCNs without nodules; both positions are recorded on the parent cyst page.

## Fields

- Kind: Cancer
- Last checked: 2026-09-24
- Also known as: Mucinous cystic neoplasm with associated invasive carcinoma (women, body and tail; 4 to 12 percent of resected MCNs); Invasive MCN; Mucinous cystadenocarcinoma of the pancreas; MCN with invasive carcinoma; Malignant mucinous cystic neoplasm
- Tags: gi; pancreatic; subtype-page
- Group: gastrointestinal
- Burden: Invasive carcinoma was present in 12 percent of 163 resected mucinous cystic neoplasms in two European and US centres and 3.9 percent of 156 in Japan; MCNs themselves are uncommon and 95 to 98 percent occur in women, almost all in the body or tail.
- Subtypes: MCN with low-grade dysplasia (adenoma; cured by resection); MCN with high-grade dysplasia (carcinoma in situ); MCN with associated invasive tubular carcinoma (treated as ductal PDAC); MCN with associated colloid or undifferentiated carcinoma with osteoclast-like giant cells
- Biomarkers: Ovarian-type stroma (progesterone and oestrogen receptor and inhibin positive) in the cyst wall (definition); Cyst diameter of 40 mm or more and mural nodules (predictors of malignancy); Cyst-fluid CEA (mucinous) without GNAS mutation (unlike IPMN); KRAS in the invasive component; Age: invasive disease in older women (55 against 44 in the Crippa series)

## Sections of this record

The page is a hub with ten sections in reading order; large sections have their own page. The same plan as JSON: https://onco.cc/api/v1/cancers/mcn-associated-carcinoma/sections.json

- Overview (on the hub): The TL;DR, the family this cancer belongs to, the organ, who gets it and what the state of the art is. https://onco.cc/cancers/mcn-associated-carcinoma/#overview [2 state-of-the-art points]
- What it is (on the hub): Anatomy, the subtypes and how they differ, how it is staged, and where advanced disease spreads. https://onco.cc/cancers/mcn-associated-carcinoma/#what-it-is [4 subtypes]
- Finding it (on the hub): How it shows itself, how it is confirmed, what screening exists, and the biomarkers clinicians test for. https://onco.cc/cancers/mcn-associated-carcinoma/#finding-it [4 biomarkers]
- Treating it (on the hub): The standard of care by setting, the medicines, surgery and radiotherapy named in it, and the regimens behind them. https://onco.cc/cancers/mcn-associated-carcinoma/#treating-it [2 settings, 2 decisions with options]
- Evidence (on the hub): Trials recruiting now, the landmark trials, the key papers and what they mean, the latest literature, and the milestones year by year. https://onco.cc/cancers/mcn-associated-carcinoma/#evidence [3 milestones]
- The science (on the hub): The molecular landscape: the targets and how often each appears, the pathways, the mechanics stages and the preclinical models. https://onco.cc/cancers/mcn-associated-carcinoma/#science [1 target, 2 pathways]
- Where you are (own page): Cases by country, the UK and NHS pathway and other country lenses, and the expert centres with trials on record. https://onco.cc/cancers/mcn-associated-carcinoma/where-you-are/
- Living with it (on the hub): The decisions you may face, the aids that walk through them, the warnings on record, the first sixty days and the questions to ask. https://onco.cc/cancers/mcn-associated-carcinoma/#living-with-it [12 questions, 2 red cards]
- What is coming (own page): Everything in development, the open problems and what is being done about them, the roadmaps, and what changed on this record. https://onco.cc/cancers/mcn-associated-carcinoma/coming/ [2 medicines, 2 open problems]
- Data (own page): Every connected record, the notes, the JSON, Markdown and RDF twins, and where the record came from and when it was checked. https://onco.cc/cancers/mcn-associated-carcinoma/data/ [17 connected records]

## Standard of care

- Resectable: Distal pancreatectomy with splenectomy (minimally invasive where expertise exists, DIPLOMA), pancreatoduodenectomy for the rare head lesion; adjuvant chemotherapy as for ductal adenocarcinoma when invasive carcinoma is found. ([Distal pancreatectomy (removal of the body and tail of the pancreas, usually with the spleen)](https://onco.cc/terms/distal-pancreatectomy/), [Robotic & minimally invasive surgery](https://onco.cc/technologies/robotic-surgery/), [FOLFIRINOX / mFOLFIRINOX](https://onco.cc/drugs/folfirinox/), [Neoadjuvant / adjuvant / perioperative](https://onco.cc/terms/neoadjuvant-adjuvant/))
- Advanced: Treated as pancreatic ductal adenocarcinoma: resection with adjuvant chemotherapy when removable, the chemotherapy rows of the parent page when not; the parent record carries the trials. ([FOLFIRINOX / mFOLFIRINOX](https://onco.cc/drugs/folfirinox/), [Gemcitabine + nab-paclitaxel](https://onco.cc/drugs/gemcitabine-nab-paclitaxel/))

## State of the art

- MCN is recognised as a less aggressive entity than once thought (17.5 percent malignant in the 2008 series) once separated from IPMN by ovarian stroma.
- Minimally invasive distal pancreatectomy is non-inferior for margin status in pancreatic cancer (DIPLOMA 2023).

## Open problems

- Whether small MCNs without nodules can be safely observed rather than resected divides the Japanese and European guidance.
- No trial addresses adjuvant treatment for MCN-associated carcinoma specifically.

## Sources

- Wikipedia: https://en.wikipedia.org/wiki/Pancreatic_mucinous_cystic_neoplasm
- Crippa, Ann Surg 2008: mucinous cystic neoplasm of the pancreas is not an aggressive entity, 163 resected patients: https://doi.org/10.1097/sla.0b013e31811f4449
- Yamao, Pancreas 2011: mucinous cystic neoplasm with ovarian-type stroma, Japan Pancreas Society multi-institutional study: https://doi.org/10.1097/mpa.0b013e3181f749d3
- Korrel, Lancet Reg Health Eur 2023: DIPLOMA, minimally invasive versus open distal pancreatectomy for resectable pancreatic cancer: https://doi.org/10.1016/j.lanepe.2023.100673
- Nagtegaal, Histopathology 2020: the 2019 WHO classification of tumours of the digestive system: https://doi.org/10.1111/his.13975
- Adsay, Am J Surg Pathol 2001: colloid (mucinous non-cystic) carcinoma of the pancreas: https://doi.org/10.1097/00000478-200101000-00003

## Connected records

- cancers: [Colloid (mucinous non-cystic) carcinoma of the pancreas](https://onco.cc/cancers/pancreatic-colloid-carcinoma/), [Intraductal papillary mucinous neoplasm and other pancreatic cystic precursors](https://onco.cc/cancers/ipmn-cystic-precursors/), [Invasive carcinoma arising in an intraductal papillary mucinous neoplasm (IPMN-associated carcinoma)](https://onco.cc/cancers/ipmn-associated-carcinoma/), [Mucinous ovarian cancer](https://onco.cc/cancers/mucinous-ovarian-cancer/), [Pancreatic ductal adenocarcinoma](https://onco.cc/cancers/pancreatic/), [Solid pseudopapillary neoplasm of the pancreas](https://onco.cc/cancers/solid-pseudopapillary-neoplasm/), [Undifferentiated carcinoma of the pancreas with osteoclast-like giant cells](https://onco.cc/cancers/pancreatic-undifferentiated-carcinoma-ogc/)
- technologies: [Cytotoxic chemotherapy](https://onco.cc/technologies/cytotoxic-chemotherapy/), [Endoscopic ultrasound and EBUS systems](https://onco.cc/technologies/endoscopic-ultrasound-systems/), [Histopathology & immunohistochemistry](https://onco.cc/technologies/histopathology-ihc/), [MRI](https://onco.cc/technologies/mri/), [Robotic & minimally invasive surgery](https://onco.cc/technologies/robotic-surgery/)
- targets: [KRAS](https://onco.cc/targets/kras/)
- drugs: [FOLFIRINOX / mFOLFIRINOX](https://onco.cc/drugs/folfirinox/), [Gemcitabine + nab-paclitaxel](https://onco.cc/drugs/gemcitabine-nab-paclitaxel/)
- pathways: [Pancreatic cancer (KEGG map)](https://onco.cc/pathways/pancreatic-cancer-signalling/), [RAS / RAF / MEK / ERK (MAPK)](https://onco.cc/pathways/ras-mapk/)
- terms: [Distal pancreatectomy (removal of the body and tail of the pancreas, usually with the spleen)](https://onco.cc/terms/distal-pancreatectomy/), [Grade](https://onco.cc/terms/tumour-grade/), [High-risk stigmata and worrisome features of pancreatic cysts (IPMN and MCN surgical criteria)](https://onco.cc/terms/pancreatic-cyst-high-risk-stigmata/), [Neoadjuvant / adjuvant / perioperative](https://onco.cc/terms/neoadjuvant-adjuvant/), [Resection margins (R0 / R1 / R2)](https://onco.cc/terms/resection-margins/)

---
JSON: https://onco.cc/api/v1/entities/mcn-associated-carcinoma.json