Adenomatoid tumors
Adenomatoid tumors are benign tumors of mesothelial origin, commonly found in the male epididymis and the female reproductive organs, such as the fallopian tubes, ovaries, and uterus. These tumors are characterized by a glandular appearance, which can sometimes lead to confusion with malignant conditions like adenocarcinoma. While they can occur in various locations, including the heart and lymph nodes, the most prevalent sites are in the genital tract. Adenomatoid tumors typically present asymptomatically, and when they do cause symptoms, they may lead to pain or discomfort due to their size. They are often discovered incidentally during procedures like tubal ligation or surgeries. Diagnosis can be challenging, as imaging studies may misrepresent them as other benign tumors like uterine fibroids. Treatment generally involves surgical removal, and the prognosis is excellent, with a low risk of recurrence. Overall, adenomatoid tumors are not associated with known risk factors, and their incidence is difficult to determine due to the lack of biopsies for many cases.
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Adenomatoid tumors
ALSO KNOWN AS: Adenofibromyomas, Recklinghausen’s tumors
RELATED CONDITIONS: None
DEFINITION: An adenomatoid tumor is a small benign tumor of mesothelial origin usually occurring in the male epididymis or female fallopian tube, ovary, or uterus. Rarely, these tumors can be seen within the testes and prostate. Extragenital adenomatoid tumors have also been identified in the heart, mesentery, pleura, lymph nodes, omentum, and adrenal glands. Because of its glandular appearance, it is sometimes confused with an adenocarcinoma or metastatic carcinoma, especially signet ring cell carcinoma.
Risk factors: There are no known risk factors for adenomatoid tumors.
Etiology and the disease process: An adenomatoid tumor is a benign hamartoma that is a malformation resulting from faulty development in an organ. It is made up of an abnormal mixture of tissue elements normally present at that site. Most adenomatoid tumors are composed of fibrous tissue separated by numerous slitlike pseudotubular spaces crossed by peculiar threadlike bridging strands, which are their typical morphologic feature. The most common benign tumor of the epididymis, adenomatoid tumors usually arise in the tail of the epididymis and may rarely invade adjacent testicular parenchyma. According to the American Cancer Society in 2013, adenomatoid tumors can also develop in the mesothelium (the lining formed by specialized cells called mesothelial) of certain reproductive organs. In men, adenomatoid mesothelioma often grow in the ducts within the testicles. In women, tumors will often begin in the fallopian tubes. Although they may occur at any age, they are most commonly seen in patients between twenty and fifty years of age and are usually asymptomatic. Although usually under five centimeters (two inches) in size, they can grow quite large under hormonal influence.
Incidence: True incidence of adenomatoid tumors is not known as most tumors are never biopsied because of their small size and similarity to leiomyomas (fibroids) of the uterus. When found in the male genital tract, these tumors are usually seen in an extratesticular location, usually involving the epididymis, representing approximately 30 percent of tumors arising in the paratesticular area.
Symptoms: Adenomatoid tumors are typically asymptomatic. However, when adenomatoid tumors occur in the genital tract, they can grow quite large and can be painful.
Screening and diagnosis: Often mistaken for uterine fibroids on magnetic resonance imaging, the radiologic appearance can vary from solid to cystic depending on the relative amounts of cystic spaces, smooth muscle, and fibrous tissue contained within the tumor. Ultrasound is useful in diagnosing adenomatoid tumors of epididymal origin. They usually appear as a round or oval, solitary, solid, well-circumscribed mass of variable echogenicity measuring between five millimeters and five centimeters (1/5 inch to two inches). Occasionally they may appear cystic sonographically and rarely appear plaquelike and ill-defined.
Treatment and therapy: Surgical removal.
Prognosis, prevention, and outcomes: Excellent. Because of the benign nature of adenomatoid tumors, little follow-up care is needed beyond removal. Recurrence is not typical.
Bibliography
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Damjanov, Ivan, and Gregor Mikuz. "Tumors of the Testis and Epididymis." Atlas on the Human Testis. Ed. Davor Ježek. London: Springer, 2013. 179–231. Print.
Derchi, Lorenzo E., and Michele Bertolotto. "Scrotal Masses." Abdominal Imaging. Eds. Bernd Hamm and Pablo R. Ros. Berlin: Springer, 2013. 1877–86. Print.
Farah, M., et al. "Epididymal Adenomatoid Tumour: A Case Report." Cureus 15.10 (23 Oct. 2023). doi.org/10.7759/cureus.47505.
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Makkar, M., et al. "Adenomatoid Tumor of the Testis: A Rare Cytological Diagnosis." Journal of Cytology 30.1 (2013): 65–67. Print.