Introduction
The mucocele of the appendix is also known as an appendiceal mucocele. It is a fluid-filled growth that develops on the mucosal membrane of the appendix. It is a rare disease entity discovered incidentally during surgery. It is similar to acute appendicitis. This cyst develops when there is a mucus plug forming in the mucus membrane. These mucoceles on the appendix are generally benign growth, not cancerous. However, in certain instances, it could develop into a cancerous lesion and extend throughout the entire appendix, leading to life-threatening consequences. It shows non-specific symptoms that resemble several common illnesses. During normal radiological examinations or endoscopic examinations, it is frequently found accidentally. Therefore, a histopathological examination is mandatory to confirm the diagnosis.
What Is the Incidence of the Mucocele in the Appendix?
The incidence of appendicular mucoceles is very rare. It is more common in women and people with age over 50. It is usually found accidentally during surgery of the appendix and complicates the procedure.
What Are the Types of the Appendiceal Mucocele?
Four histological forms exist and are as follows:
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Retention Mucinous Cyst: It mainly occurs due to obstruction that leads to the development of mucus retention in the cavity.
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Mucosal Hyperplasia: Hyperplasia (increase in size) is seen in this type.
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Mucinous Cystadenoma: It is a more common variant.
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Mucinous Cystadenocarcinoma: The luminal dilatation in mucinous cystadenomas can be up to six centimeters. It is seen less frequently than mucinous cystadenomas. This tumor has an odd propensity to penetrate and expand beyond the appendix to the peritoneum. It is more commonly spread through the lymphatic or vascular channels. Additionally, in severe cases, the entire peritoneal cavity swells up with an adhesive, semi-solid mucus; this condition is known as pseudomyxoma peritonei.
What Are the Causes of Appendiceal Mucocele?
A rare disorder, mucocele appendix, can happen for various reasons. Most frequently, benign and malignant diseases are to blame. These conditions lead to mucous discharge, a buildup of mucus, and obstruction of the appendix. Other than these, mucosal hyperplasia may also be the cause. Mucinous cystadenoma or mucinous cystadenoma carcinoma are two other mucosal disorders that can result in the development of mucocele. In addition, inflammatory or obstructive processes may combine to cause it. These factors contribute to the development of mucoceles on the mucous layer of the appendix, which can be fatal for the patient if left untreated.
What Are the Symptoms Associated With the Appendiceal Mucocele?
Appendicular mucoceles typically have a vague clinical presentation, with one-fourth of the patients asymptomatic. The symptoms are as follows:
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Patients most frequently have right lower quadrant pain.
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Urinary symptoms are uncommon.
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Palpable masses have been recorded in half of the cases. Though the mass in this patient significantly displaced the bladder, there were no symptoms related to the urinary system.
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On the belly, swelling and inflammation are evident.
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The bulk of the abdomen becomes palpable. The lower right quadrant of the abdomen may be painful at the site of the appendix.
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In addition to these localized symptoms, the patient may develop acute appendicitis.
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Patients may also have weight loss, nausea, and vomiting.
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Last but not least, the patient may encounter unexpected and inexplicable changes in bowel habits.
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Excessive blood loss can result in fatality in an anemic patient.
How to Diagnose the Mucocele of the Appendix?
As appendicular mucocele is a rare disorder with vague presenting symptoms, preoperative identification is challenging. But preoperative diagnosis is crucial to choose the right surgical method and to avoid intra-operative problems, particularly peritoneal dissemination. An ultrasound examination is the first-line diagnostic method that distinguishes between benign and malignant mucoceles.
Fifteen millimeters or higher diameter has been established as a criterion for diagnosing appendicular mucocele. A computed tomography (CT) scan is crucial to verify the diagnosis and gauge the severity of the illness. Fine needle aspiration cytology is typically not advised. A colonoscopy is a crucial diagnostic tool for the presence of colon cancers. An elevated appendicular orifice and a yellowish mucus discharge may present on colonoscopy.
What Is the Treatment of the Mucocele in the Appendix?
The preferred course of treatment is surgery, which must be performed quickly because a tumor cannot be completely ruled out as the cause of the mucocele. Preoperative diagnosis is crucial to prevent unintentional rupture and the growth of pseudomyxoma peritonei after surgery. With good outcomes, laparoscopic resection has been used. However, suppose the tumor is spread to the peritoneum. In that case, a laparoscopic dissection is useful in grabbing the appendix, pneumoperitoneum (presence of air or gas in the abdomen), or transporting the specimen through the abdominal wall. Precautions include using bowel-holding graspers (non-traumatic) to handle the mucocele and a non-permeable bag to deliver the specimen. If the mucocele appendix is benign, the preferred course of treatment is the surgical removal of the entire organ. The surgical procedure is an appendectomy, and the condition is treated appropriately without complications. Malignant mucocele may develop so severely that it cannot be treated surgically and requires radiation or chemotherapy.
What Are the Complications of the Mucocele of the Appendix?
Melena, pyonephrosis, and intestinal bleeding/obstruction are complications of appendicular mucocele. A serious side effect is pseudomyxoma peritonei, brought on by either iatrogenic (illness due to medical examination) or spontaneous mucocele perforation.
Appendix Mucocele Cancer
Mucoceles are swollen sacs filled with mucus from the appendix's mucous membrane. In a ruptured appendix, the body's cells will expand and develop into cancerous cells; however, these expanding appendix cells still generate mucin, a gel-like substance enabling cancer to spread to other parts of the body. Malignant mucoceles are challenging to treat and potentially fatal for the patient. The treatment option depends on the mucocele type, ranging from benign to malignant.
Conclusion
Appendiceal mucocele is an uncommon condition. It can mimic acute appendicitis. A proper preoperative diagnosis is a must to prevent intraoperative and postoperative problems. Ultrasound, CT scan, and histopathological examination are done to confirm the diagnosis. An early diagnosis with prompt treatment is necessary to avoid further complications. If mucocele is left untreated, pseudomyxoma peritonei develops a fatal condition. For treatment, it requires surgical excision.
