I’m sitting here going through my very old post-surgery emails and I’ve stumbled upon one from December that made my jaw, once again, drop. A study was published in late 2018 about a woman who was discovered to have an endometrial cyst inside her pancreas…WHAT? It’s super-duper rare.

As usual, this isn’t meant to scare you. Just inform you…

As you know…I’m prone to following studies down rabbit holes and satisfy my curiosity. Today is no different! Read on, dear Reader…read on!

What & Where is the Pancreas?

I’ve often heard of the pancreas but never looked into where it was and what it does. I know it’s somewhere in my torso…but never bothered or cared to know more. But now? I’m all over it!

It’s a gland about six inches long that’s smashed in the abdominal cavity, surrounded by the liver, spleen, small intestine, stomach, and gallbladder. The pancreas aids in digestion by secreting lovely secretions affectionately called pancreatic juices. It also helps regulate blood sugar via pancreatic hormones: insulin and glucagon.

Symptoms of Pancreatic Endometriosis

From what I’ve been able to read, it appears that symptoms may include:

• Epigastric pain (pain or discomfort below your ribs);
• Left upper quadrant pain (the section of your torso on your left : belly button to boob and everything in between); and,
• Unexplained weight loss.

Diagnosis & Treatment

The good news is it appears that tissue growth and/or cysts are oftentimes spotted with CT scans, MRIs, or endoscopic ultrasound. These may lead physicians to exploratory surgery. And it seems that resection (removal) of the diseased portion of the pancreas is the best option for treating pancreatic Endometriosis.

If you suffer from symptoms and want to begin steps to ensure you DON’T have pancreatic endometriosis, I do believe you’ve got quite the journey ahead. Document your symptoms, track your diet and any triggers, and begin by pursuing imaging studies (xray, CT, MRI, ultrasound, and endoscopic ultrasounds). Talk to your doctor. Do understand that it’s very rare, but there are documented cases below:

Science!

Okay, on with the studies, including the one that brought me here!

A study from 1984 was of a 36-year-old woman who had complained of epigastric pain and was being seen at a hospital in New York. Fourteen months earlier, she was hospitalized with acute pancreatitis and sonogram studies were normal. Now back in the NY hospital, she had no prior history of surgeries, no abnormal periods, her pain was not during her periods, and she didn’t have a problem with alcohol. She had right upper quadrant fullness and lower left quadrant discomfort. Palpitation of her torso was normal, as well as a rectum exam and blood tests. An x-ray showed a hiatal hernia and a distorted duodenal bulb (a portion of the small intestine that is up by the stomach). And a sonogram revealed a small buidup of calculi in her gallbladder as well as an cyst inside her pancreas. A laparatomy was performed; they couldn’t feel any stones in her gallbladder, but located the 4cm cyst in the tail of her pancreas. Piercing of the cyst showed a yellow-ish fluid. They removed part of her pancreas, as well as her gallbladder and spleen. Biopsy of the cyst proved it was lined with endometrial tissue, and hence her diagnosis of pancreatic endometriosis AND no evidence of any prior pancreatitis was found…Her symptoms subsided after her surgery. Go figure.

In 1986, a study was published of a 40-year-old woman who had recurrent left flank pain for a year and a half. When palpitated, doctors could feel a mass near her kidney, but all other physical examinations were normal. An angiography showed the upper part of her left kidney was compressed. A procedure known as an excretory urography was performed and the left side was shown to secrete less, due to a mass which had displaced her left ureter. An ultrasound led doctors to believe a cyst was present. When punctured, the cyst oozed a chocolate-colored, thick fluid. Exploratory surgery was performed and the 8cm cyst was visualized compressing the kidney. While there, her surgeons also found a cyst on her pancreas. Pathology showed the cysts were Endometriosis.

In 2000, a 47-year-old Japanese woman had complained of epigastric pain, back pain, nausea, and vomiting. A CT scan and ultrasound found a cyst on her pancreas. A surgery was performed to remove the diseased portion of her pancreas and pathology confirmed it as an endometrial cyst.

In 2002, a 21-year-old Korean woman went to the hospital because of ongoing epigastric pain and she had lost 20 pounds in one year. She had no prior surgical history, her periods were normal, and her family history was normal. A physical exam and blood tests were also normal. A CT scan showed a 4cm cyst on her pancreas. She underwent a pancreatectomy to remove the infected portion of her pancreas and the biopsy showed it positive as Endometriosis. The rest of her pancreas was normal.

A study published in 2004 was of a 34-year-old woman who was admitted to the hospital due to severe abdominal pain. She had intermittent left upper quadrant pain for the past three years. Between those painful flares, she was pain-free. A CT scan showed an 8cm mass in the tail of her pancreas and a chest x-ray showed a nodule in her right lower lung lobe near her diaphragm. She underwent a CT-guided biopsy to take a sample of the cyst on her pancreas with fine needle aspiration and they collected 100ml of dark brown fluid from the cyst. A few imaging scans later, and doctors decided to do exploratory surgery. “Small plaque-like lesions” were found on her liver and diaphragm. Other lesions were found on her spleen and they found the cyst on her pancreas. A portion of her pancreas and spleen were moved, as well as the suspicious lesions. Biopsy confirmed the cyst in the pancreas was Endometriosis. The authors of the study stress that, although rare, “a cystic lesion in the pancreas must have endometriosis in the differential diagnosis.” At least consider the option…

In 2011, a 35-year-old woman had recurrent, severe pain in her upper left abdominal quadrant. The pain had persisted for three months and an examination revealed a cyst inside her pancreas. A portion of her pancreas was removed and a biopsy showed it to be an endometrial cyst.

A July 2012 study was of a 42-year-old woman who was hospitalized due to epigastric pain. A CT scan revealed tissue changes around her pancreas as well as possible cancerous growths. Her pain resolved, but later at a follow-up exam, another CT found additional tumor growth. Physical examination and bloodwork was normal. She was referred to a local university hospital’s pancreatic team. More CT scans found swelling and tissue changes around the tail of her pancreas. Pancreatitis was suspected. An MRI led the team to suspect Endometriosis. They learned that she had a history of irregular periods (but they weren’t painful), and that her sister had Endometriosis. Since the imaging studies were not conclusive, exploratory surgery was performed by a team of gynecological and gastrointestinal surgeons. Evidece of old Endometriosis activity was noted in her Pouch of Douglas, she had a chocolate cyst on her left ovary (they removed her left ovary), and cystic tissue was found on the pancreas; which came back from pathology as Endometriosis.

In 2016, a study was published of a post-menopausal, 72-year-old woman was preliminary diagnosed with pancreatic cancer and was referred out for further testing. She had increasing abdominal pain in the upper left quadrant of her torso. And her medical history included an umbilical hernia, an appendectomy, hypertension, her gallbladder was removed, a hysterectomy, and a surgical hernia repair. “There was no known history of pancreatitis or endometriosis.” Her abdomen was bloated and tender, especially in the area of her pain. Imaging studies showed a mass on her pancreas. Pathology came back as Endometriosis, and she was symptom-free five years after her surgery.

A February 2017 study is of a 43-year-old woman who had previously been admitted to the hospital for one day of severe epigastric pain and was diagnosed with acute pancreatitis. A CT scan and an endoscopic ultrasound at that time indicated a cyst on the tail-end of her pancreas. It was pierced with fine needle aspiration and brown fluid was retrieved. Fast forward to three months later and she’s at a medical clinic due to worsening abdominal pain, fatigue, diarrhea, anorexia, and having lost 15 pounds in the past three months. Although she had a previous diagnosis of Endometriosis, she did not have painful periods. Additional imaging studies confirmed the presence of the cyst and surgery found the 16cm cyst inside the tail-end of her pancreas. That section, as well as a portion of her spleen, were removed. No other evidence of Endometriosis was found. Pathological examination showed the cyst was full of “gray-green cloudy fluid” and came back as pancreatic Endometriosis.

In December of 2018, a 26-year-old woman reported abnormal periods and was hospitalized due to left abdominal pain. It hurt even when she wasn’t on her period. Her medical history only revealed that she had a prior c-section, but no history of Endometriosis or pancreatitis. A CT Scan found a 7cm cyst inside of her pancreas, which was confirmed in both an MRI and endoscopic ultrasound. A benign tumor was suspected and surgery was performed to remove part of her pancreas as well as her spleen. A biopsy was performed and it was found that she had endometrioma insider her pancreas. She underwent surgery and they removed the portion of her pancreas, as well as a bit of her spleen which was affected by the mass.

Oooh! A new study has hit my inbox! Finally! In May of 2021, Case Reports in Surgery published an article of a 51-year-old woman who had an enlarged pancreas that also had a cyst on the tail. The cyst was discovered in 2014 and was suspected to be intraductal papillary mucinous neoplasm (cells which may cause pancreatitis or pancreatic cancer). It did not appear to be malignant and was therefore monitored. Later, she presented to the hospital due to epigastric pain, back pain, diarrhea with greasy stools, and anorexia. She had a prior hysterectomy, but denied any symptoms of Endo. Labs were normal. An MRI showed the defect on her pancreas. The pancreas and spleen were surgically removed and she was discharged from the hospital six days later. Pathology found the “cyst” to be consistent with Endometriosis. A year later she denied any recurrent symptoms and imaging studies showed no regrowth of any cysts.

**Updated May 24, 2021**

Resources:

Acta Radiologica Open (Article; Sept. 2016) – A Rare Case of Pancreatic Endometriosis in a Postmenopausal Woman and Review of the Literature

Case Reports in Surgery (Article; May 2021) – A Rare Case of Pancreatic Endometriosis Masquerading as Pancreatic Mucinous Neoplasm

Europe PMC (Abstract; Jan. 2000) – A Case of Hemorrhagic Cyst of the Pancreas Resembling the Cystic Endometriosis.

Gastroenterology (Article; June 1984) – Endometrial Cyst of the Pancreas

Healthline – What’s Causing my Epigastric Pain and How Can I Find Relierf?

Journal of Minimally Invasive Gynecology (Abstract; July 2012) – Endometriosis of the Pancreas (you may access the full article here)

Korean Journal of Internal Medicine (Article; 2002) – A Case of Pancreatic Endometrial Cyst

Pancreatic Cancer Action Network – What is the Pancreas?

Southern Medical Journal (Article; Oct. 2004) – Endometriosis of the Pancreas Presenting as a Cystic Pancreatic Neoplasm with Possible Metastasis

Surgery Today (Abstract; July 2011) – Pancreatic Endometrial Cyst: Report of a Case

The Japanese Society of Internal Medicine (Article; Dec. 2018) – A Rare Case of Pancreatic Endometrial Cyst and Review of Literature

The Journal of Urology (Abstract & Article; Jan. 1986) – Pancreatic Endometriosis Presenting as Hypovascular Renal Mass (you may access the full article here)

World Journal of Gastroenterology (Article; Feb. 2017) – Pancreatic Endometrial Cyst Mimics Mucinous Cystic Neoplasm of the Pancreas

~ Again, I am a layman.  I do not hold any college degrees, nor mastery of knowledge.  Please take what I say with a grain of salt.  If curious, do your own research 
Validate my writings.  Or challenge them.  And ALWAYS feel free to consult with your physician. Always.  Yours ~ Lisa