Dear Editor,
I have read with interest the paper titled “Case report of ovarian torsion mimicking
ovarian cancer as an uncommon late complication of laparoscopic supracervical hysterectomy”
written by Ciebiera et al. and published in “Menopause Review” in 2016; 15: 223-226.
The authors described what they call an unusual presentation of an adnexal +10 cm
large mass with adnexal torsion in a 46-year-old woman who previously had laparoscopic
hysterectomy with unilateral adnexectomy due to fibroids, and a haemorrhagic cyst
of her left ovary. The patient had preoperative tumour markers assessment, pelvic
ultrasound, and pelvic computed tomography. The Authors claim that all these studies
indicated an “elevated risk of malignancy”, and because of this, laparotomy with midline
vertical incision was performed. During surgery they collected multiple cytological
smears and “mid-surgical evaluation with the possibility of conversion to a full oncological
profile (excision of the cervix, greater omentum, appendix, and lymphadenectomy)”
was planned. To document their thesis, two preoperative sonographic images of the
smooth-shaped solid-cystic mass are presented. Despite a detailed description of the
preoperative diagnostic methods, there are a number of important issues around the
design, analysis, and reporting of this case that I wish to raise.
First, ultrasound scans, contrary to the macroscopic picture of the removed tumour,
are not presented in colour, so the vascularity of the mass is difficult/impossible
to assess. Moreover, these “representative” scans were made in greyscale only, and
because of this they do not contain a colour Doppler map on the right side of the
images. Therefore, we have to believe the Author’s claim that the subjective assessment
of the examiner suggested high vascular content, at least in some portions of this
mass. Secondly, since preoperative levels of serum CA-125 antigen and HE-4 protein
were 41.1 U/ml and 83.1 pmol/l, respectively, the Authors claim that the calculated
Risk of Ovarian Malignancy Algorithm (ROMA) was 31.5%, which, according to their beliefs,
“classified the patient in the ‘high risk for ovarian cancer’ group”. Unfortunately,
this is not so easy. The patient, despite hysterectomy at the age of 46, was still
premenopausal, because the menopause in women after uterus removal is stated as +50
years of age in most scientific papers. Premenopausal status makes a possibility of
repeated haemorrhagic ovarian cyst more likely, and at the same time, the use of common
serum ovarian tumour markers assessment much less reliable. According to e.g. the
“he4test.com” website [1] containing an online calculator of ROMA, for this particular
patient ROMA risk was equal to 22.3% (see attached Fig. 1).
Fig. 1
Screenshot from the Risk of Ovarian Malignancy Algorithm online calculator
According to the Japanese based Fujirebio Company, which, along with the Abbott Company,
USA, also manufactures HE4 tests and distributes ROMA risk manual calculators, the
premenopausal woman with such tumour marker levels had a risk of app. 21-22% (Fig.
2).
Fig. 2
ROMA premenopausal risk
This value indicates only slightly elevated risk, strongly depending on the medical
centre type (oncologic vs. non-oncologic) to which the patient was referred. According
to the International Ovarian Tumour Analysis (IOTA) group studies, high risk of malignancy
in gynaecological cancer centres, such as the Authors’ hospital, should probably be
set at 25-30% [2]. Theoretically, for postmenopausal women the manually calculated
ROMA risk in this case was app. 32% (Fig. 3).
Fig. 3
ROMA postmenopausal risk
Thirdly, when diagnosis of a malignant ovarian mass is suspected, many recent studies
have documented much better predictive values of preoperative sonography as compared
to tumour markers or combined models, such as ROMA or RMI. For instance, in 2013 Kaijser
et al. [2] concluded that the IOTA logistic regression model 2 (LR2), also used by
the Authors in the presented case, shows better diagnostic performance than ROMA for
the characterisation of a pelvic mass in both pre- and postmenopausal women. Also,
in a recent meta-analysis Nunes et al. [3] found that simple rules protocol could
be used in 76-89% of tumours, and in all analysed studies it was an accurate test
for the diagnosis of ovarian cancer. Until last year, a second opinion by an ultrasound
expert was required when this method in its classical version could not be applied
[4]. In 2016 the IOTA group published a paper showing that the use of simple rules
is possible in all cases of adnexal tumours, and the risk of malignancy of an adnexal
mass can be assessed even without any calculator [5].
The problem with preoperative diagnosis of the presented case is related to the wrong
use and misunderstanding of the IOTA group terms and definitions by the Authors. They
have assigned tumour malignant feature M4 to an apparently regularly shaped solid-cystic
mass. The International Ovarian Tumour Analysis definition of the M4 feature is straight-forward:
“an irregular multilocular-solid tumour larger than 100 mm”[4]. However, the presented
scans of their tumour contain only one B feature, namely B3 which is “acoustic shadows”.
A similar situation has probably occurred with the Author’s attempt to use the IOTA
group LR2 model. Ciebiera et al. state that: “The LR2 IOTA model was also used and
determined the risk for malignancy to be approximately 52%”. There is no explanation
of which variables they have used and how exactly the calculation was done; was is
on the website or mobile device or with the mathematical formula? In any event, the
six variables of LR2 should be correctly scored as in Fig. 4.
Fig. 4
Risk calculation in the IOTA logistic regression model 2, Android application
The risk calculated by the model was only app. 3.89%, which is very far from 50% as
estimated by the Authors [2]. It seems that the presented case was completely wrongly
assessed before the operation, and computed tomography scanning brought nothing new
to the ultrasound diagnosis. Furthermore, a midline vertical incision laparotomy could
be spared to this woman, with laparoscopy or minilaparotomy performed instead of a
larger surgery. The reason for the wrong preoperative diagnosis seems to be obvious:
it was a complete misunderstanding of the IOTA terms and definitions used to describe
adnexal masses. It is not clear from the paper if any of the Authors of this case
report has taken and passed the IOTA MCQ test for this reason, but even not having
a relevant certificate should not prompt such a flawed opinion and decision.
Lastly, I would like to raise the question of the possibility of increased risk of
adnexal torsion after laparoscopic supracervical hysterectomy. The Authors do not
use any publications to support their thesis, nor can it be found in the medical literature.
The main risk of laparoscopic hysterectomy is related to the morcellation of a uterine
malignancy, and subsequent dissemination of occult cancer, or even uterine sarcoma.
These dangerous complications, and probably not adnexal torsion, must be balanced
by the risks of increased numbers of laparotomies.
In conclusion, I am happy to observe an attempt to use the IOTA models such as LR2
and, as recently suggested by the Polish Gynaecological Society Guidelines [2015],
also Simple Rules for the trial of preoperative discrimination between benign and
malignant tumour, as presented in this case report. However, the Author’s analysis
does not allow the reader of this paper to draw any reliable conclusions with respect
to such benign and acute mass discrimination. Both ultrasound examiners and gynaecological
surgeons must be aware that early diagnosis and appropriate surgical management of
adnexal torsion is the only way to prevent complications like necrosis of the ovary
and, in women planning pregnancy, to preserve their future fertility. To improve reporting
of ultrasound-based prediction model results of various tumours including adnexal
torsion, it is extremely important to be aware of the IOTA definitions and terms.
This in turn may assist in the correct preoperative risk estimation and diagnosis
of these patients.
Sincerely,
Prof. Artur Czekierdowski, MD, PhD
IOTA Group member since 2006