Biomedical Engineering Reference
In-Depth Information
Chapter 3
Cancer
3.1 Biological Introduction
Ovarian cancer (OvCa) is the fifth leading cause of tumor-related deaths in the
Western world (with little change in its incidence in recent decades) [4], the
second most common gynecological carcinoma, and the leading cause of death
from gynecological malignancies. In fact, its mortality rate is high, compared
to other cancers [52]. Significant contributors to its high mortality rate are
the vague or absent symptoms in the early stages of the disease, the lack
of reliable tumor markers, and the recurrences, generally fatal, despite good
initial responses to chemotherapy. For these reasons, long-term survival is
rare since 70% of the patients present at diagnosis extensive and widespread
intraperitoneal dissemination throughout the abdomen and the pelvis [62].
The majority ( 90%) of ovarian cancer stems from surface epithelium that
overlies the ovary [126].
Clinically, ovarian cancer progression is divided into four stages by the
Federation Internationale de Ginecologie et d'Obstretique (F.I.G.O.) based
on tumor spread. In the early stage (stage I), the disease is confined to one or
both the ovaries, while in stage II it has begun spreading, with localized ex-
tensions into the adjacent pelvic tissues and organs. As the disease progresses
into stage III, the tumor has spread to the upper abdominal cavity until at
the final stage IV it metastatizes, proliferating and reaching distant, extra-
peritoneal sites. In this last phase, after detaching from the ovarian capsule,
the original malignant cells exfoliate, as single individuals, aggregates, or mul-
ticellular spheroids, from the primary tumor into the abdominal cavity, where
they disseminate transported by peritoneal fluids and ascites. In particular,
the ascites, present in almost one third of ovarian cancer patients, is a gen-
erally voluminous exudative fluid, containing selected cell populations mainly
consisting of tumor cells, lymphocytes, and mesothelial cells, which facilitates
tumor cell transport throughout the abdominal cavity [320].
The migration of neoplastic cells is also regulated by environmental factors
such as ECM components, cytokines, growth factors, or chemotactic factors,
mainly secreted by the mesothelium, an epithelial-like monolayer [287], that
lines the organs of the abdominal cavity and is the elective site of ovarian car-
33
Search WWH ::
Custom Search