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Retroperitoneal anatomy
By
Dr. Khattab KAEO
Prof. & Head of Obstetrics and Gynaecology Department
Faculty of Medicine, Al-Azhar University, Damietta
Introduction
The subperitoneal area of
the true pelvis is partitioned into potential spaces
by the various organs &
their
respective
fascial
coverings
and
by
the
selective thickenings of the
endopelvic
fascia
into
ligaments and septa.
The retroperitoneal spaces
The paravesical space: This is developed by dissect
ing between the external iliac vessels and the anter.
division of the internal iliac artery (precisely, the
superior vesical artery) lateral to the bladder. The
uterine artery forms the posterior boundary of the
space, while the levator ani muscles form its floor.
First, expose the external iliac vessels near their
entrance into the femoral canal by dividing the round
ligament near the deep inguinal ring. Note where the
circumflex iliac vein crosses the external iliac artery.
The anterior division of the internal iliac artery lies
just medial. On the lateral side of the paravesical
space lies the obturator fossa containing blood ves.,
nerve and lymph nodes. Blunt dissection following
the inward pelvic slope can be continued to the
pelvic diaphragm. The space is limited superiorly by
the lateral umbilical ligament.
Cardinal ligament
Cut round ligament
going through the deep
inguinal ring
Developing the retroperitoneal spaces
This is particularly useful in the following
conditions (indications):
1- Malignancy.
2- Endometriosis.
3- Chronic PID.
4- Tubo-ovarian abscess.
5- Large or interligamentous liemyoma.
6- Redsidual ovaries.
7- Hypogastric artery ligation.
The pararectal space: It is bound laterally by
the levator ani, medially by the rectal pillars,
and posteriorly above the ischial spine by the
anterolateral aspect of sacrum. Peripheral
part of the cardinal ligament and the uterine
artery divides the paravesical & the pararectal spaces.
To best develop the pararectal space, dissect
between the first portion of the anterior
division of the internal iliac artery laterally
and the ureter medially. The uterosacral
ligament and the ureter are located very
near to each other between the rectovaginal
and pararectal spaces. Remain close to the
rectum to avoid the internal iliac vein and its
side wall tributaries.
The vesicovaginal space: Incise the
vesicouterine peritoneal fold transversely.
Push the bladder down bluntly or by
sharp dissection. Moist gauze packing
usually controls any encountered slow
venous bleeding. A common error is to
dissect too close to the cervix and fail to
get into the proper plane. Developing this
space gives access to the vesicouterine
ligament which contains the ureter as it
passes to the bladder.
The rectovaginal space: Incise the
peritoneum between the insertion of
the two uterosacral ligaments (the
rectal pillars contain the middle
haemorrhoidal arteries). Bluntly dissect
the vagina from the rectum by
sweeping the palm along the posterior
vaginal wall. For adherent areas, sharp
dissection against the vagina is used.
The vesicovaginal and rectovaginal
spaces may be considerably altered. In
such instances, developing the
paravesical and the pararectal spaces
first is very helpful.
The prevesical and presacral spaces:
The prevesical space can be developed
by gently dissecting the areolar tissue
immediately posterior to the symphysis
pubis. The presacral space can be
developed by gently incising the overlying parietal peritoneum. One may
place the sigmoid colon to the left.
Inside this space, encased in fat, is the
sympathetic nerve plexus (the
presacral nerve) in addition to the
middle sacral artery and vein.
1988 FIGO SURGICAL staging:
Stage I: Tumour limited to the uterus.
Stage IA: Limited to the endometrium.
Stage IB: Invaded ½ the myometrium.
Stage IC: Invaded >½ the myometrium
Stage II: Extends to the cervix.
Stage IIA: Endocervical glandular involvement
Stage IIB: Cervical stromal involvement.
Stage III: Spread to the pelvis.
Stage IIIA: Invasion of uterine serosa &/or adnexa or +ve peritoneal cytology.
Stage IIIB: Vaginal metastasis.
Stage IIIC: Pelvic or paraaortic LN metastasis.
Stage IV: Advanced pelvic or distant metastasis
Stage IVA: Bladder or bowel mucosa invasion.
Stage IVB: Distant and/or inguinal LN metastasis.
CIS is often sharply demarcated
Histologic types: 90% of endometrial adenocarcinomas are of the endometrioid type.
Degrees of differentiation: Poorly differentiated
tumours are less responsive to adjuvant progestogen therapy than well-differentiated
tumours. Also, they deeply invade the myometrium early, while well-differentiated
tumours tend to grow exophytically in the
cavity.
G1: ≤5% of a non-squamous or non-morular
solid growth pattern.
G2: 6%-50% of a non-squamous or nonmorular solid growth pattern.
G3: >50% of a non-squamous or non-morular
solid growth pattern.
10% uncommon types: clear cell,
papillary serous, mucinous carcinoma and undifferentiated tumours.
Clear cell adenocarcinoma is identi
cal to that of the cervix, vagina &
ovary. It is a high-risk tumour;
early stages are comparable to G3
endometrioid adenocarcinoma.
Papillary serous carcinoma tends
to spread intra-abdominally, and is
refractory to most standard therapy
Lymphatic spread: Lymphatic spread from
the mid and lower portions is similar to that
of the cervix. Fundal tumours spread through
the broad and infudibulopelvic ligaments to
the hypogastric, external iliac, common iliac
& aortic nodes or through the round ligament
to the superficial and deep lymph nodes.
High risk endometrial adenocarcinoma:
1- >50% of the myometrial thickness is invaded
(stage IC), involvement of the cervix (stage
IIA, B) or adnexa (stage IIIA).
2- Poorly differentiated (grade 3).
3- Villoglandular type of endometrioid adenocarcinoma if invaded the myometrium.
4- The uncommon types.
Presentation: Early growths are polypoidal; surface ulceration and necrosis
 peri-/post-menopausal bleeding.
Because this is ominous to both the
patient & physician, delays in diagnosis
are uncommon.
Late cases may present
with intermittent pus-like discharge.
Postmenopausal bleeding or bloodymucoid discharge indicates cancer in
the genital tract in 50% of cases.
The uterus feels symmet
rically enlarged by the mass If affecting
a senile uterus, clinical enlargement
Work-up: History and examination:
Most patients are in their 60s & 70s.
Coexisting DM, hypertension & obesity.
Endometrial biopsy for all wo
men >40 with IUB It is also indicated if
endometrial cells are noted on a Pap
smear of a postmenopausal woman or
if atypical glandular cells are noted on
a smear of a premenopausal woman.
Biopsy establishes the diagnosis with
high sensitivity and specificity.
Ultrasonography could be re
assuring if endometrial thickness is <3
Screening: Only worthwhile in highrisk popul:
white, obese, on estrogen or tamoxifen, nulli
para, with PCOS, granulosa cell tumour, personal or family history of breast/ovarian/
colon cancer. Arrange 2-4 visits/year. Endometrial sampling is done using Vabra aspirator (postsounding) which is diagnostic in 90100% of cases +ve results  additional endo
cervical sampling, but endometrial curettage
is unnecessary. If D & C is chosen:
- At the end a polyp forceps is used to remove a polyp
- If 1 swipe of the curet produces obvious endometrial
carcinoma, further curettage is not necessary (may
disseminate tumour cells).
If there is hyperplasia, look for accompanying carcinoma or ovarian tumour.
The same work-up should be followed even if an
obvious cause of postmenopausal bleeding such as
Treatment
Surgery: TAH BSO is the mainstay treatment.
Chemotherapy: Progestational therapy may  responses, but cures are unusual.
MPA: For CIS: 400 mg in 4 w in divided doses, then
400 mg/month (5).
For carcinoma: 400 mg/day for a week, then 400
mg 3 times/w for 2 w before surgery with the same
course is given postoperatively if the tumour is extended for >1/3 of the myometrium.
Chemotherapy is attempted with distant metastasis. It
includes cis-/ carbo-platin, doxorubicin & paclitaxil.
Radiotherapy: Stage IIB necessitates preoperative
external radiotherapy then TAH BSO. If the tumour
is of low risk, no further treatment is required.
PORTEC (Post Operative Radiation Therapy in Endometrial Carcinoma):
External radiotherapy lowers the rate of local recurrence to 4% (Vs 14% in the no-radiotherapy group).
However, the complication rate is 25% among the
irradiated patients Vs 6% in the no-radiotherapy group.
For stage Ia G1,2 no postoperative radiotherapy is required.
For stage Ib G1,2 postoperative brachytherapy is required. For
Thank
you
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