Keywords
diagnostic imaging - gynecologic oncology - gynecologic operation - ovarian neoplasms
- splenosis
Splenosis is a rare disease, which is often discovered incidentally years after surgical
procedures on the spleen or traumatic splenic lesions with subsequent splenectomy.
Through injury of the splenic capsule, splenic cells are able to spread into the abdominal
cavity comparable to disseminated peritoneal metastases. In the majority of cases
with reported splenosis, the splenic tissue organizes itself like a congenital accessory
spleen on various ectopic intra-abdominal locations. There are rare cases, especially
with additional laceration of the diaphragm, where splenic tissue is even found in
the thoracic cavity.[1]
[2]
Case Report and Case Presentation
A 62-year-old patient (II Gravida/II Para) presented with diarrhea for several weeks
and a palpable tumor of the lower abdomen. Her medical history was unremarkable, except
for having had a splenectomy after traumatic splenic lesion in her childhood. Clinical
examination showed a palpable mass in the lower abdomen without any further anomalies.
Using vaginal ultrasound, we detected ascites and suspicious adnexal masses. On the
right ovary, there was a 38 × 28 mm large, homogeneous, solid, hypervascular tumor
([Fig. 1A]) and on the left ovary, we found an 80 × 54 mm large, solid-cystic, hypervascular
structure ([Fig. 1B]). The laboratory workup revealed increased CA 125 levels (403 U/mL, elevated 11.5×
upper norm limit).
Fig. 1 (A) Ultrasound image of the right ovary: 38 × 28 mm large, homogeneous, solid and hypervascularized
tumor. (B) Ultrasound image of the left ovary: 80 × 54 mm large, homogeneous, solid-cystic
and hypervascularized tumor.
Further diagnostic workup included a coloscopy and gastroscopy without any pathological
findings and a computer tomography (CT) scan of the abdomen and thorax ([Fig. 2]). In the portal venous phase of the CT scan, we detected more than 10 smoothly bordered,
homogeneous, and contrast-enhancing lesions, primarily in the peripancreatic fatty
tissue and in addition adjacent to the greater curvature of the stomach, perihepatic,
mesenterial, and several tumors in the left subphrenic space. One of the lesions was
located at the right pelvic wall with contact to the colon and rectum as well as to
a large inhomogeneous retro-uterine tumor in the small pelvis without separating tissue.
The perihepatic, peripancreatic, and mesenterial lesions were isodense to hyperdense
compared with the liver parenchyma (density of 104 to 122 Hounsfield units [HU]).
Based on the preoperative suspicion of advanced ovarian cancer (FIGO IIIc), the patient
underwent staging laparotomy for cytoreductive surgery.
Fig. 2 Presurgical portal venous phase computer tomography scan with more than 10 smoothly
bordered, homogeneous, contrast enhancing lesions, most of them in the peripancreatic
fatty tissue as well as adjacent to the greater curvature of the stomach, perihepatic
and mesenterial. Several of the tumors are in the left subphrenic space. One of the
tumors was located at the right pelvic wall with contact to the colon and rectum as
well as to a big inhomogeneous retro-uterine tumor in the small pelvis, without separating
tissue. The perihepatic, peripancreatic an mesenterial lesions were isodense to hyperdense
compared with the liver parenchyma (density of 104 to 122 Hounsfield units).
The intraoperative situs showed the typical appearance of advanced ovarian cancer
with disseminated peritoneal metastases. In addition to superficial tumor spread in
the abdominal cavity and adnexal masses, there were multiple peritoneal implants,
involving the mesentery and serosa of the small intestine, macroscopically similar
to splenic tissue ([Fig. 3]). Although the lesions showed distinct morphological features, distinguishing them
from peritoneal carcinomatosis, one of the largest nodes (40 × 25 × 20 mm) covering
the rectum was resected and send to intrasurgical frozen section assessment, to histologically
confirm that the nodules were not another manifestation of the advanced ovarian cancer.
The lesion was then identified as intra-abdominal splenosis. Final histopathological
analysis corroborated the diagnosis. The resected tissue showed the typical structure
of splenic tissue with red and white pulp covered by a fibrous capsule from which
trabeculae entered into the parenchyma ([Fig. 4]). Histopathological examination of the resected greater omentum yielded 12 additional
foci of splenosis.
Fig. 3 Intraoperative presentation of splenosis in the greater omentum.
Fig. 4 Histological presentation of splenosis. The tissue shows the typical structure of
splenic tissue with red and white pulp covered by a fibrous capsule from which trabeculae
enter into the parenchyma (Hematoxylin and Eosin staining, magnification ×25, measuring
bar 1,000 µm).
With the intrasurgical confirmation of splenosis, the remaining foci of splenosis
could be spared and surgery was limited to clinically suspected cancer manifestations.
Cytoreductive surgery comprised hysterectomy, bilateral adnexectomy, deperitonealization
of the recto-uterine pouch, omentectomy, appendectomy, and resection of several peritoneal
cancer lesions from the mesentery and resulted in macroscopic complete resection.
Histology showed a high grade serous ovarian cancer, pT3b, N0, M0, L0, V0, Pn0 (FIGO
IIIb). The patient was hospitalized for 12 days and afterwards underwent chemotherapy
with six cycles of carboplatin/paclitaxel, as well as a maintenance therapy with bevacizumab
for 1 year. After surgery and the first cycle of chemotherapy, CA125 levels returned
to normal (10.5 U/mL) and did not increase again during therapy. We could discharge
the patient into oncological follow-up care without any clinical evidence of remaining
or recurrent cancer (follow-up time so far 17 months after surgery).
Discussion and Conclusion
One of the most important goals in treatment of advanced epithelial ovarian cancer—
determining overall survival and progression free survival—is complete resection of
the tumor mass in primary surgery.[3] However, avoiding unnecessary procedures and limiting surgery strictly to cancer
manifestations can reduce the rate of complications and consequently improve patient
outcome. Therefore, differentiating between benign lesions and cancer manifestations
is of great importance when both of them occur simultaneously. In this particular
presented case, the challenge comprised of the differentiation between intra-abdominal
manifestations of splenosis and peritoneal cancer. If splenosis had been diagnosed
prior to surgery, even the resection of the singular rectal node for histological
confirmation could have been avoided. Although our patient did not suffer from complications,
operating on the intestine is associated with the risk of intestinal dysfunction and
infection of the abdominal cavity and stenosis. Moreover, patients might even benefit
from the residual splenotic tissue as there are indications that patients with splenosis
might restore at least partial reticuloendothelial function after splenectomy.[4]
Despite its rare occurrence, there are other cases described in literature, where
splenosis led to complications during surgery. Nicolas et al for example presented
a case of a 30-year-old patient, who showed excessive weight gain after gastric band
surgery and was therefore indicated for conversion into a gastric sleeve.[5] During the operation, they detected many foci of splenosis, for example, at the
gall bladder, the stomach, the liver, and the diaphragm.[5] Because of the high risk of massive bleeding through erosion of the gastric band
into the splenic tissue, the gastric band had to be removed and the surgery terminated
due to the difficult anatomic situation.[5]
Another pitfall was described by Sorensen et al, which shows the consequences of misdiagnosis
for the individual patient and strongly emphasizes the importance of awareness.[6] In their case, curative surgery for a patient with carcinoma of the Papilla vateri
was denied because of peritoneal carcinosis diagnosed in a CT scan.[6] Although this is a highly uncommon procedure, a biopsy of one of the peritoneal
lesions was performed to secure the diagnosis of peritoneal cancer.[6] Histopathological analysis of the biopsy revealed splenic tissue. Thus, the patient
could undergo the surgical resection of the tumor via curative Whipple procedure.[6]
These cases emphasize the importance of diagnosing splenosis prior to surgery. However,
it is a big challenge in clinical routine and especially awareness of this disease
is limited. Although the lesions are visible in CT scans with similarity to splenic
tissue in density and enhancement of contrast agent, reliable diagnosis is difficult.[7] Magnetic resonance imaging cannot yield further information either in most of the
cases the lesions are, similar to the spleen, hypointense on T1-weighted images and
hyperintense on T2-weighted images. Furthermore, the manifestations present an irregular
enhancement of contrast agent in the arterial phase and a homogeneous enhancement
in the late contrast phase.[7]
[8]
[9]
After imaging diagnostics, several patients were misdiagnosed with malignomas like
hepatocellular carcinoma,[10] lung cancer,[2] or gastrointestinal stromal tumor[11] resulting in unnecessary surgical procedures and avoidable morbidity. Therefore,
further diagnostic tools are warranted to differentiate splenosis from carcinomas
in imaging.
One method is the Tc-99m-tagged heat-damaged RBC scan (Tc-99m-DRCB), where heat denaturated
red blood cells are tagged with Tc-99m. These denaturated cells accumulate in the
red pulp and can be used to detect splenic tissue.[7]
[9]
[12]
[13]
[14]
Another technique is using scintigraphy with 111Indium-tagged thrombocytes, which gather in the reticuloendothelial system of splenic
tissue.[7]
[13] In rare cases, diagnosis is even further complicated by simultaneous incidence of
splenosis and malignant disease, similar to the presented case. Misinterpretation
could have fatal consequences for patients as potential curative treatment is replaced
by palliative therapy for advanced disease. Preoperative awareness with subsequent
additional diagnostics is important to avoid under- or overtreatment in those patients.
Since there are no distinct symptoms of splenosis, patients who underwent splenectomy
should generously undergo prior examination for remaining splenic tissue. Especially
in the absence of Howell-Jolly-Bodies, the lack of increase in reticulocyte count
and the presence of antipneumococcal antibodies in nonvaccinated patients[7]; one of the earlier mentioned imaging techniques should be considered prior to an
exploratory surgery. As we were preoperatively not aware of a potential simultaneous
splenosis and the diagnosis was only suspected during surgery, no Tc-99m-DRCB or scintigraphy
with 111Indium-tagged thrombocytes was performed in the presented case.
To our knowledge, this is the first published case of simultaneous incidence of peritoneal
carcinosis and splenosis. Most of the cases in the literature only report splenosis
as a differential diagnosis to peritoneal carcinomatosis.[6]
[15]
[16]
In conclusion, intra-abdominal splenosis is a rare event in patients who underwent
surgical procedures of the spleen or traumatic splenic lesions. Coincidence of splenosis
with malignancies can mimic peritoneal cancer spread to the abdominal cavity and may
lead to misinterpretation of the tumor extent. However, reliable discrimination of
cancer masses and splenosis is essential for the prevention of unnecessary surgery
and avoiding further morbidity, as well as for the correct classification of clinical
tumor stage and the appropriate treatment scheduling. Consideration of splenosis as
a potential differential diagnosis for intra-abdominal tumor lesions is important,
especially in patients with corresponding medical history, and physicians should be
aware of this rare event also in cases of simultaneous malignancies.
