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Ultrasonography in Gynaecological Cancers 115
Figure 2. Preoperative determination of the extent of disease
and prognostic factors necessary for planning treatment strate-
gies. The size and tumour topography within the cervix (1), the
parametrial involvement (ventral, lateral, dorsal; right and left) (2) resolution endoluminal probe allows a detailed view of
with the possible affection of the urinary tract (3), the presence
of metastatic pelvic (4) and paraortic lymph nodes (5) and others.
cancer (15). On the other hand, it is not a broadly available
technique and has known contraindications for the
patient (Table 1). Its accuracy and usage depend on the
presence of an experienced radiologist with knowledge
of gynaecologic oncology. Therefore, data reporting high
accuracy of MRI in the staging of cervical cancer, which
mostly came from single-unit studies, was not replicated
in a multicenter study organised by the American
College of Radiology Imaging Network (ACRIN) and
Gynaecology Oncology Group (GOG) (16-19).
Figure 3. Ultrasound for cervical cancer staging. Transvaginally inserted probe (A). Transrectally inserted probe (B). Transabdominal
scanning (C), including steps of transabdominal scanning (1-Evaluation of parenchymatous organs, 2- Assessment of peritoneal surfaces
including omentum, 3-Detection of inguinal and retroperitoneal lymphadenopathy).
Conversely, an ultrasound scan can be carried out
directly by gynaecological oncologists with all the
benefits that their knowledge of the disease brings. High
the pelvic structures and tissue planes between the cervix
and adjacent organs comparable to MRI. The probe can be
introduced transvaginally or transrectally. The transrectal
approach is preferred for cervical cancer due to the risk of
bleeding from the tumour while performing transvaginal
scan. Additionally the transrectal approach guarantees
better acoustic conditions to show the distal portion
of the cervix (20). The combination of transvaginal/
transrectal and transabdominal ultrasound allows the
complete assessment of the abdomen and pelvis for
staging of cervical cancer (Figure 3) (21). In the case of
para-aortic lymph node involvement, the assessment can
also be supplemented with an examination of peripheral
supraclavicular nodes using linear probe.
Among features that are unique to ultrasound are
the direct visualization of tumour vascularization and
the dynamic aspects of the examination. This plays
an important role in the identification of residual
tumours (22). The extent of tumour is established
using a combination of sonomorphology and Doppler
as we know how the different histotypes appear on
ultrasound. Doppler alows us to visualise the tumour’s
vessels within a tumour. Cervical cancer is mostly
squamocelullar with hypoechogenic appearance and
a high density of tumour vessels, while adenocancer is
iso- or hyperechogenic and less visible in some cases with
abundant neovascularization (Figure 4) (22). Dynamic
aspects of the examination permit the operator to assess
the mutual sliding of contiguous tissues against each
other (23). The sliding effect makes it possible to define
relations between the neoplasm and bladder, rectum and
pelvic walls (23, 24). In addition, the operator can gently
exert pressure on the probe to assess the elasticity of the
cervical stromal tissue. This maneuver reveals cervical
cancer as a rigid, solid mass infiltrating the cervical
stroma (23).