Struma Ovarii or Strumal Carcinoid: An Overview

Introduction:

The ovaries, which are each roughly the size of an almond, generate ova in addition to the hormones progesterone and estrogen. On the ovaries, ovarian tumors are abnormal growths. Ovarian tumors are a result of aberrant cell proliferation. Ovarian cancers fall into one of two basic categories: a benign mass of tissue is one that develops gradually on the ovary's surface or within the ovary. It can turn into a cancerous tumor if neglected. A malignant mass of tissue is one that contains cancerous cells and is aberrant.

Germ cells, which may differentiate into any sort of cell since they are undifferentiated, are where teratomas develop. When the cells' differentiation process is disturbed, a teratoma results. The most prevalent variety of ovarian germ cell tumors is mature teratomas. They might be either benign (non-cancerous) or malignant. A dermoid cyst is another name for a mature teratoma. When a woman is in her reproductive years, they are most prevalent (from teens to forties). Ovarian teratomas include monodermal teratomas like struma ovarii, juvenile teratomas, and mature cystic teratomas (dermoid cysts). The term "struma" describes abnormal thyroid gland hypertrophy.

A carcinoid tumor is a malignant growth that develops slowly. Traditionally, the embryologic location of origin, morphological pattern, and affinity for silver have been used to categorize carcinoid tumors. Histology is used as the initial basis for the diagnosis of a carcinoid tumor, and positive immunohistochemistry staining is used as confirmation. Depending on where the main tumor resides, the clinical characteristics of carcinoid tumors—such as their aggressiveness or propensity for metastasis, and their prognosis might differ significantly.

What Is Struma Ovari/ Strumal Carcinoid?

A particular kind of ovarian teratoma known as struma ovarii or strumal carcinoid contains thyroid tissue mixed in with a neuroendocrine tumor (carcinoid) component. It is a monodermal or specialized teratoma that is mostly made of mature thyroid tissue. Monodermal teratomas are made entirely or mostly of one kind of tissue. The thyroid component that is present in the strumal carcinoid might be either adenomatous or carcinomatous, or it can be a normal thyroid that contains colloidal particles. The tumors are reportedly generally unilateral and have a diameter of up to 26 cm.

What Are the Symptoms of Struma Ovarii/ Strumal Carcinoid?

Strumal carcinoid is rarely reported in the literature. Sometimes, no definite symptoms are present. The symptoms discussed in the literature are as below

• Women usually present with abdominal or pelvic pain.

• A pelvic mass.

• Ascites, excessive abdominal fluid.

• Constipation.

• Heavy menstrual bleeding.

• Amenorrhea, absence of menstrual cycle.

• Vaginal discharge.

• Alopecia, hair loss.

• Weight loss.

• Ulcerated skin lesions.

• Hyperthyroidism.

Case studies show that eight percent of patients had endometrial hyperplasia, hirsutism (excessive hair growth similar to males), or virilism (development of physical characteristics of a male) as a result of steroid hormone synthesis.

How Is Struma Ovarii/ Strumal Carcinoid Diagnosed?

• Ultrasound: On an ultrasonogram that was done for another purpose, an ovarian tumor could be unintentionally discovered. In ultrasound, struma ovarii shows as a solid mass that is heterogeneous.

• Computed Tomography (CT): To do a diagnostic evaluation of the cyst's fat attenuation.

• Magnetic Resonance (MR) Imaging: Using fat-saturation methods to specifically identify the sebaceous component.

• Elevated CA-125: Measuring the amount of the protein cancer antigen 125 (CA 125) in the blood

• In Hyperthyroid Patients: Free thyroxine (T4) and/or triiodothyronine (T3), as well as serum thyroglobulin, are increased while serum thyroid-stimulating hormone (TSH) is low. The thyroid gland either has little to no radioiodine uptake or none at all, whereas the pelvic shows steady radioiodine uptake.

• Histologic Findings: The diagnosis of struma ovarii in female patients who report a pelvic mass is often made postoperatively based on histologic evidence of thyroid follicles in the resected ovary.

• Diagnosis of Malignant Struma Ovarii: The usual cytopathologic characteristics of papillary thyroid cancer or tumor invasion, metastases, or recurrence (for follicular cancer) must be positively diagnosed in order to meet the diagnostic criteria for malignant struma ovarii.

How Is Struma Ovari/ Strumal Carcinoid Treated?

1. Salpingo-oophorectomy

It is nearly invariably benign, and treatment with a simple oophorectomy or salpingo-oophorectomy is successful, despite the fact that the carcinoid component of the strumal carcinoid has been thought of as a malignant transformation of struma ovarii. The surgical removal of both ovaries and both fallopian tubes is known as a salpingo-oophorectomy. In cases of metastatic illness, patients with malignant struma ovarii may require further treatment in addition to oophorectomy. Surgery needs to be postponed for those with struma ovarii and newly identified overt hyperthyroidism till they have sufficient thyroid condition control (usually three to eight weeks). Ordinarily, patients with subclinical hyperthyroidism (low TSH, normal free T4, and T3) can move on with elective procedures. The doctors provide beta blockers to elderly (>50 years old) or younger patients with cardiovascular disease prior to surgery, unless it is contraindicated, and will be tapered after recovery. Treatment for benign struma ovarii involves surgically removing the ovarian tumor, usually with a unilateral oophorectomy. However, because of the preoperative worry about ovarian cancer, some individuals undergo complete hysterectomy, which involves surgical removal of the uterus together with unilateral or bilateral salpingo-oophorectomy.

2. Additional Treatments for Malignant Struma Ovarii

In cases of metastatic condition, patients with malignant struma ovarii may also require radioactive iodine therapy in addition to oophorectomy. For the treatment of women with functional metastatic struma ovarii, radioiodine has been employed.

What Are the Complications of Struma Ovari/ Strumal Carcinoid?

Recurrence has been seen in certain cases even after surgical removal. Below are the risk factors for the recurrence of struma ovarii

• Patients with the gross expansion of the tumor outside of the ovary into nearby tissues have a greater probability of recurrence.

• Large lesions >4 centimeter, a genetic mutation.

• Patients having histological findings other than conventional papillary carcinoma.

There is a need for follow-up in patients who have undergone major surgery, especially in those whose condition was severe at the time of diagnosis.

How Does Struma Ovarii Cause hyperthyroidism?

One of the ovarian tumors is Struma Ovarii that is defined by presence of thyroid tissue comprising > 50 percent of the overall mass which most commonly occurs as a teratoma. Usually, thyroid hormones are not produced by the Struma Ovarii but there are cases in which it produces thyroid hormones which results in hyperthyroidism. They are usually treated with anti thyroid drugs and laparoscopic tumor resection.

Conclusion:

Struma ovarii is a rare tumor. The clinical, laboratory and radiological results of the individuals that are described are quite varied. Pathologic results support confirming the diagnosis. Benign struma ovarii can only be treated surgically, by excision. Malignant struma ovarii patients may require adjuvant therapy, and fortunately, recurrence is rare.