SARCOMA, MELANOMA, METASTATIC CANCER AND COLPOSCOPY

Sarcoma

The most important sarcoma of the cervix is the embryonal rhabdomyosar¬coma, which occurs in children and young adults. The tumor, when examined under medical microscopes, has grape-like polypoid nodules, the botryoid sarcoma, and the diagnosis depends on the recognition of rhabdomyoblasts using tissue culture microscopy. Leiomyosarcomas and mixed mesodermal tumors involving the cervix primary but are more likely to be secondary to uterine tumors.

Malignant Melanoma

On rare occasions, melanosis has been seen in the cervix. Thus malignant melanoma may arise de novo in this area. Histopathologically, it stimulates melanoma elsewhere, and the prognosis depends on the depth of invasion into the cervical stroma when tissue samples are examined and applied with tissue culture microscopy techniques.

Metastatic Cancer

The cervix is commonly involved in cancer of the endometrium and vagina. The latter is rare, and most lesions that involve the cervix and vagina are designated as cervical primaries. Consequently, the clinical classification is that of cervical neoplasia extending to the vagina, rather than vice versa. Endometrial cancer may extend into the cervix by three modes: direct extension from the endometrium, submucosal involvement by lymph vascular extension, and multifocal disease. The latter is most unusual, but occasionally a focus of adenocarcinoma may be seen in the cervix, separate from the endometrium. This lesion should not be diagnosed as metastasis but rather as “multifocal disease.” Malignancies involving the peritoneal cavity (like ovarian cancer) may be found in the cul-de-sac and extend directly into the vagina and cervix. These types of malignancies should be diagnosed using tissue biopsy applied with tissue culture microscopy. Carcinomas of the urinary bladder and colon occasionally extend into the cervix. Cervical involvement by lymphoma, leukemia, and carcinoma of the breast, stomach, and kidney is usually part of the systemic spread. However, an isolated metastasis to the cervix may be the first sign of a primary tumor elsewhere in the body.

Small Cell Carcinoma

The aggressiveness small cell (neuroendocrine type) carcinoma of the cervix has been studied and it was noted that it is similar to the small cell carcinoma that arises from the bronchus. At the time of diagnosis (biopsy with tissue culture microscopy), it is usually disseminated with bone, brain, liver, and bone marrow being the most common sites of metastases. Pathologic diagnosis is aided by the finding of neuroendocrine granules on an electron microscope as by immunoperoxidase studies that are positive for a variety of neuroendocrini such as calcitonin, insulin, glucagon, somatostatin, gastrin, and adrenocorticotropic (ACTH). In addition to the traditional staging for cancer of the cervix, these patients should undergo bone, liver, and brain scanning, as well as bone marrow aspiration and biopsy with tissue culture microscopy.

Colposcopy of the Invasive Lesion

For patients with suspected early invasive cancer based on Papanicolaou (Pap) test results and a grossly normal-appearing cervix, colposcopic examination or examination thru gynecologic microscope is mandatory. Colposcope is a lighted magnifying instrument used by a gynecologist to examine the tissues of the vagina and the cervix. Colposcopic findings that suggest invasion are 1) abnormal blood vessels, 2) irregular contour with loss of surface epithelium, and 3) color tone change. Colposcopically directed biopsies may permit the diagnosis of frank invasion and thus avoid for diagnostic cone biopsy, allowing treatment to be administered without delay.

Abnormal Blood Vessels

Abnormal vessels may be looped, branching, or reticular. Abnormal looped vessels are the most common and arise from the punctation and mosaic vessels present in cervical intraepithelial neoplasia (CIN). As the neoplastic growth proceeds, the need for nutrition leads to proliferation of the blood vessels, and the vessels at the surface produce double and triple loops.

These surface tufting vessels then proliferate and push out over the surface of the epithelium in an erratic fashion. Some are straight, although most have a loop, and corks in a j-shaped pattern.

Abnormal branching vessels arise from the cervical stroma and are pushed to the surface as the underlying cancer invades and pushes upward. The normally branching cervical vessels are best observed over nabothian cysts. In this area, the branches are generally at acute angles, with the caliber of vessels becoming smaller after branching, much Iike the arborization of a tree. The abnormal branching blood vessels seen with cancer tend to form obtuse or right angles, with the caliber sometimes enlarging after branching. Sharp turns, dilatations, and narrowings also mark the behavior of these vessels. The surface epithelium may be lost in these areas, leading to irregular surface contour and friability.

Abnormal reticular vessels represent the terminal capillaries of the cervical epithelium. Normal capillaries are best seen in a postmenopausal woman with atrophic epithelium. When cancer involves this epithelium, the surface is again eroded, and the capillary net¬work is exposed. These vessels are very fine, short, and composed of small commas with¬out an organized pattern. They are not specific for invasive cancer; atrophic cer¬vicitis may also have this appearance.

Irregular Surface Contour

Abnormal surface patterns are observed as the tumor growth proceeds using specialized medical microscopes. The surface epithelium ulcerates as the cells lose intercellular cohesiveness secondary to the loss of desmosomes. Irregular contour also may occur because of a papillary characteristic of the lesion. This finding sometimes can be confused with a human papilloma virus papillary growth on the cervix, and for that reason, biopsies should be performed on all papillary cervical growths.

Color Tone Change

Color tone may change as a result of the increasing vascularity, sur¬face epithelial necrosis, and in some cases, production of keratin. The color tone is a yel¬low-orange rather than the expected pink of intact squamous epithelium or the red of the endocervical epithelium.