Microinvasive Cervical Squamous Carcinoma and Invasive Cervical Cancer
Correctly diagnosing a patient for cervical malignancies requires the use of microscopes and the latest in tissue culture microscopy techniques. Information regarding cervical conization, invasive cervical cancer and squamous carcinoma will be discussed below.
Microinvasive Cervical Squamous Carcinoma
Cervical conization is required to assess correctly the depth and the linear extent of inŽvolvement of microinvasion. The earliest invasion is characterized by a protrusion from the stromoepithelial junction. This focus consists of cells that appear better differentiated than the adjacent noninvasive cells and have abundant pink-staining cytoplasm, hyperchroŽmatic nuclei, and small- to medium-sized nucleoli when viewed under medical microscopes and applied with the latest in tissue culture microscopy techniques. These early invasive lesions in the form of tongue-like processes without measurable volume are classified as InternaŽtional Federation of Gynecology and Obstetrics (FIGO) stage la1. With further proŽgression, more tongue-like processes and isolated cells occur in the stroma. The latter responds by a proliferation of fibroblasts (desmoplasia) and a band-like infiltration of chronic inflammatory cells. With increasing depth of invasion, invasion occurs at multiple sites, and the growth becomes measurable by depth and linear extent. Lesions that are less than or equal to 3 mm are classified as FIGO stage Ia1. Lesions that are greater than 3-5 mm or more in depth and less than or equal to 7 mm in linear extent are classified as FIGO stage la2. With increasing stromal inŽvasion, the involvement of capillary-lymphatic spaces is increased. Foreign body multinuŽcleated giant cells containing keratin debris, dilated capillaries, and lymphatic spaces are ofŽten seen in the stroma when applied with tissue culture microscopy techniques under a medical microscope.
The depth of invasion should be measured with the micrometer from the base of the epithelium to the deepest point of invasion. The depth of invasion is significant for the development of pelvic lymph node metastasis and tumor recurrence. Although in tissue culture microscopy, lesions that have invaded 3 mm or less rarely metastasize, patients in whom lesions invade more than 3-5 mm have positive pelvic lymph nodes in 5-8% of cases. Although the significance of the cutoff at 3 mm has not been identified completely, it may be postuŽlated that capillary-lymphatic spaces are extremely small at this level and whether they can carry tumor cells beyond the specific zone is unclear. Uneven shrinkage of tissue by fixaŽtive often creates space between the tumor nests and the surrounding fibrous stroma, stimŽulating vascular lymphatic invasion. A suspected vascular involvement with invasion of less than 3 mm should be interpreted with care. A lack of endothelial linŽing indicates that the space is shrinkage artifact rather than true vascular invasion.
Invasive Squamous Cell Carcinoma
Invasive squamous cell carcinoma is the most common variety of invasive cancer in the cervix. This is diagnosed thru pelvic examination and PAP smear. If PAP smear is positive, a colposcope is a way to view your cervix, vaginal walls and vulva with equipment that can magnify the area. Like a microscope, the colposcope allows the doctor to see more than can be observed with the eye alone. When you have changes on your Pap test that could lead to cancer, a colposcopy allows the doctor to view the abnormal cells under magnification.
Histologically using tissue culture microscopy, there are large cell keratinizing, large cell nonkeratinizing, and small cell types. Large cell keratinizing tumors are made up of tumor cells forming irregular infiltrative nests with laminated keratin pearls in the cenŽter. Large cell nonkeratinizing carcinomas reveal individual cell keratinization but do not form keratin pearls. The category of small cell carcinoma includes poorly difŽferentiated squamous cell carcinoma and small cell anaplastic carcinoma. If possible, these two tumors should be differentiated using tissue culture microscopy. The former contains cells that have small- to medium sized nuclei, open chromatin, small or large nucleoli, and more abundant cytoplasm than those of the latter. The designation of small cell anaplastic carcinoma should be reserved for lesions resembling oat cell carcinoma of the lung. It infiltrates diffusely and consists of tuŽmor cells that have scanty cytoplasm, round to oval small nuclei, coarsely granular chromatin, and high mitotic activity. The nucleoli are absent or small. The small cell neuroenŽdocrine tumors are differentiated by immunohistochemistry or electron microscopy.
Patients with the large cell type of carcinoma, with or without keratinization, have a better prognosis than those with the small cell variant. Furthermore, small cell anaplastic carcinomas behave more aggressively than poorly differentiated squamous carcinomas that contain small cells. The prognosis is affected adversely by the presence of vascular lymphatic invasion, deep stromal invasion, infiltration of parametrial tissue, and pelvic lymph node metastasis.
