Laparoscopic Splenectomy for a Congenital Epidermoid Cyst in a 15-Year-Old Child—Case Report ^†

Abstract

Splenic epidermoid cysts are rare benign congenital tumors. However, if the cyst is not completely removed, it can reoccur. Laparoscopic splenectomy in children is being conducted more often, but it is a therapeutic challenge in cases of a giant cyst. We report a case of a 15-year-old girl who presented with nausea, anorexia and abdominal pain. The ultrasound showed a giant well-defined hypoechoic cyst with diffuse internal echoes. Computed tomography revealed a cystic mass (92/124/102 mm) without contrast enhancement. Anti-Echinococcus ELISA IgG was negative, and serum tumor markers CA 19-9 79.1 U/mL (N < 34) and CA-125 39.6 U/ML (N < 35) were elevated. Before the operation, the girl was vaccinated for Haemophilus influenzae, Pneumococci and Meningococci. Laparoscopic splenectomy was performed. The patient’s postoperative course was uneventful. Histopathology indicated a cyst walled by multilayered squamous epithelium positive for cytokeratin AE1/AE3. The diagnosis epidermoid cyst was confirmed.

1. Introduction

Splenic cysts are unusual findings in pediatric surgery. There are different classifications [1,2,3]. According to Fowler’s classification, they are categorized as primary epithelial (true) cysts and secondary without epithelium (pseudocysts). Primary cysts are 25% of the cases and can be subdivided in congenital, traumatic, inflammatory and neoplastic. Secondary cyst account for 75% of the cases and can be due to trauma, degeneration and inflammation. Martin’s classification etiologically groups primary cysts into parasitic and non-parasitic (congenital and neoplastic) [3]. Echinococcus granulosus is the most common cause for parasitic spleen cysts, and it is endemic in our region. The epithelial lining defines the type of the primary cyst—epidermoid, dermoid or endodermoid [1,2]. Epidermoid cysts have squamous epithelium; dermoid have cuboidal epithelium and dermoid have squamous epithelium with sebaceous glands, hair follicles and skin appendages. A review of 42,327 autopsies reported incidences of the spleen primary epithelial cysts (0.07%) [4]. Epidermoid spleen cysts are very rare, only 10% of the true non-parasitic cysts [5]. We present a case of a 15-year-old girl with a giant spleen epidermoid cyst [6].

2. Case Report

A 15-year-old girl was referred to our department after an ultrasound exam showing a giant spleen cyst. The girl was complaining of nausea, early satiety and fullness in the left hypochondrium after meals and after physical activity for a year. She denied having a trauma. The patient was in a good general condition, and the spleen was palpable 1 cm below the costal margin. Routine laboratory tests were within the normal ranges. The ELISA (enzyme-linked immunosorbent assay) test for Echinococcus granulosus was negative and IgE was normal at 2.41 IU (N < 100). Serum levels of carbohydrate antigen 19-9 (CA 19-9) 79.1 U/mL (N < 34) and CA-125 39.6 U/ML (N < 35) were slightly elevated. Ultrasound examination showed an enlarged spleen with a round, non-homogenous hypoechoic cyst in the upper part with a maximum diameter of 120 mm without blood flow (Figure 1). The abdominal computed tomography (CT) scan revealed a cystic mass (92/124/102 mm) without contrast enhancement. The lesion was causing medial displacement of the stomach and low-grade mass effect on the left kidney (Figure 2). Due to the size of the cysts, clinical symptoms and risk of rupture, a decision for surgical treatment was made. Preoperatively, the girl received meningococcal, pneumococcal and Haemophilus influenzae vaccine.

Conventional 4-port laparoscopic splenectomy was considered. A 10 mm umbilical port with 5 mm 30° optics was introduced. Under direct visual control, three more 5 mm ports (one epigastric and two left pararectal) were placed. A pressure of 12 mm Hg pneumoperitoneum was applied. The cyst was visualized and aspirated, and the content of the cyst was measured as 200 mL of transparent brownish fluid. The splenic ligaments were divided using the Ligasure^® device. An anatomical splenectomy with a separate ligation of short gastric and splenic vessels with clips was performed. No major blood loss during the intervention was registered. The spleen was extracted using Endo-Bag^® through the umbilical port. A tube drain 18CH was placed through the left lower quadrant port. Due to the necessity of postoperative monitoring and more intensive pain management, the patient spent four days in the Intensive Care Unit Department. During this period, no early complications were registered. The drainage was removed on the fifth postoperative day after ultrasound verification for no residual-free abdominal fluid in the peritoneal cavity. No shoulder pain, constipation, gas and bloating, fatigue or other side effects due to the carbon dioxide used in laparoscopy manifested in the late postoperative period. The patient was ambulated, and oral feeding was introduced on the third postoperative day.

The patient’s postoperative course was uneventful, and she was discharged on the seventh postoperative day. During the hospital stay, pre- and postoperatively, she was on cefuroxime and amikacin, used as a prophylaxis for overwhelming post-splenectomy infection syndrome (OPSI). On the discharge date, the patient had mild thrombocytosis 486 × 10⁹ (reference range—140–440 × 10⁹). She received home treatment with ciprofloxacin and fluconazole for five days. The follow-ups were scheduled for the fourteenth and thirtieth days after hospital discharge and revealed no complications or any complaints.

Histopathological examination showed a congenital epidermoid cyst with a fibrous capsule, lined by stratified squamous epithelium (Figure 3a). Immunostaining was performed, and the epithelium was positive for cytokeratin AE1/AE3 and negative for WT1 and calretinin (Figure 3b).

3. Discussion

Epidermoid spleen cysts are rare, though more common in females [1,2,3,7]. Fourteen cases have been reported in pregnant women [8]. However, in children, the female:male ratio is almost equal (15:13) [9]. The origin of the cysts is controversial and unsolved. According to mesothelial invagination theory, during embryogenesis, peritoneal mesothelial cells are displaced in the spleen tissue [10]. There is also the endodermal inclusion theory [4]. Other hypotheses include entrapment of germinal cells from gonads, the dorsal mesogastrium and the Wolffian duct; teratomatous origin or due to trauma with fluid collection [11,12,13,14,15]. Usually, epidermoid cysts are solitary benign lesions in a regular spleen but, in 32.2%, can be found in an intrapancreatic accessory spleen [7]. Those in the intrapancreatic spleen are much smaller than in the regular spleen (median size 4.2 cm versus 14 cm) [7]. Multilocular cysts are more common in the intrapancreatic accessory spleen [7]. Preoperatively, 90% of intrapancreatic spleen epidermoid cysts are misdiagnosed as pancreatic cancer [7]. Suspicion is also increased by the elevation of the tumor markers: carcinoembryonic antigen (CEA), CA 19-9 and cancer antigen 125 (CA-125), which are also high in pancreatic carcinomas. Malignant transformation is extremely rare but possible. Three cases are reported in the literature: in an intrapancreatic accessory spleen, in the brain and skin [16,17,18]. Epidermoid cysts are associated with increased serum markers such as CEA, CA 19-9 and CA-125 [7,19,20,21,22]. Post-splenectomy CA 19-9 is normalized [23,24]. Our patient also had elevated CA 19-9 and CA-125. We did not test CEA and CA 19-9 and CA-125 postoperatively. Normal serum CEA and CA-19 do not rule out an epidermoid cyst [24,25].

Bulgaria is an endemic country for Echinococcus granulosus, and all of our patients with cysts are screened serologically with ELISA. The method has an average sensitivity around 80% and a specificity ranging from 95% to 100% [26,27]. A negative serological result does not exclude 100% echinococcosis. A false negative result is possible in calcified cysts [28]. Serologically, the results are always discussed and interpreted parallel with radiological imaging. In case of a highly suspiciously patient for hydatid disease, the child receives preoperatively prophylaxis with anthelmintics and antihistamines. Our patient’s ELISA was negative, and there were no signs for echinococcosis on the ultrasound and CT imaging and was not treated with the abovementioned drugs.

In adults, the most common symptoms include left upper abdominal mass (42.1%), left upper abdominal pain (28.9%), epigastric pain (24.3%) and fullness (20%) and nausea and vomiting (9.6%), and 28.7% of the patients were asymptomatic [7]. The percentage of incidentally found epidermoid cysts in children is even higher at 35.7% [8]. Our girl presented with nausea, early satiety and fullness in the left hypochondrium. Sometimes, an epidermoid cyst can demonstrate complications such as infection, rupture and hemorrhage [23,29,30]. The most common cause of infection is Salmonella [29,31]. Six cases with rupture were reported in patients with splenic cysts [32]. In pregnancy, splenic rupture in the last trimester is a serious complication with incidences at 4.5% and a high (almost 70%) mortality rate [32]. Ultrasonographically, epidermoid cysts are well-defined round lesions with diffuse internal echoes. Peripheral calcifications, septations and trabeculations are possible [22,33]. Computed tomography is helpful but not determinative for the diagnosis. Based only on ultrasound and CT, a giant epidermoid cyst with internal septations was misdiagnosed as a splenic lymphangioma [34]. Large splenic cysts more than 5 cm should be treated surgically because of increased risk for growth, rupture and hemorrhage [1]. Magnetic resonance imaging (MRI) could provide more details about the content of the cyst and the presence of complications such as inflammation or major splenic vessels involvement. Depending on the modality, the cyst can appear hyperintense on T2-weighted imaging and hypointense on T1-weighted imaging, if there is no hemorrhage [34]. MRI with contrast can also help differentiate spleen hemangioma and hamartomas. Hemangioma demonstrates a progressive centripetal pattern of enhancement, which later becomes uniform, whereas hamartomas show early heterogenous enhancement [35].

The differential diagnosis of the congenital epidermoid cysts includes a wide variety of medical conditions. The most common of them are the entity of the acquired splenic cysts (trauma, parasitic, metastatic and other splenic masses); calcifications (such as a result of a chronic tuberculosis, histoplasmosis, chronic granulomatous disease, splenic infarction), pancreatic cysts, etc. [36].

As a contemporary diagnostic and more detailed method, the endoscopic ultrasound could be very helpful in describing the characteristics of the spleen and the cyst, as well as the relations to the adjacent structures and blood vessels [37].

Scintigraphy with 99 m technetium sulfur colloid and 67-gallium citrate is also utilized [34].

According to the variety of publications, splenectomy leads to some potentially dangerous disorders in the immune functions of the young patients, due to certain immune response functions of the spleen in childhood, such as opsonizing antibodies production; bacterial inactivation or filtering (especially, capsulated bacteria, phagocytosis and T- and B-cell lymphopoietic function) [38]. Most of them are common and more active before the age of two years. Therefore, part of the reticuloendothelial system the spleen has also important hematologic functions.

No matter if a total splenectomy or a partial splenectomy is carried out, the vaccination prophylaxis should follow the same schedule. It is advised that the vaccination term for the splenectomy to be planned at least 2 weeks before surgery and, for the emergency ones, should be done at least 14 days after surgery [39]. There is a slightly higher preponderance in using the conjugated type of vaccines, due to the fact that they stimulate thymic T cells, which are not affected from the splenectomy and present a separate circle of the immune response [40].

Another hematologic study prompts that, even in successfully vaccinated children, prolonged antibiotic treatment should be recommended in order to prevent potentially dangerous and sometimes fatal severe post-splenectomy bacterial infections [41]. Our patient had fifteen days of antibiotic prophylaxis and five days with antimycotic. Usually, first-line antibiotics of choice are penicillin VK, amoxicillin twice daily, erythromycin or trimethoprim sulfamethoxazole [41]. We used cefuroxime and amikacin during the hospital stay and five days of ciprofloxacin and fluconazole after discharge.

There are few studies reporting no statistically significant higher risk for developing SARS-CoV-2 infections in splenectomized children [42].

Fine needle biopsies under radiological or ultrasound control are discussed in the literature but are not recommended due to a higher risk of dissemination or complications, such as massive hemorrhage [43].

Surgical treatment of giant splenic cysts is always indicated in cases with symptoms or to prevent complications. There is a variety of operative approaches for splenic resection. The most common used and cited in the literature are percutaneous aspiration, sclerotherapy, decapsulation, fenestration, unroofing, conventional or laparoscopic total splenectomy (TS) and partial splenectomy (PS). The first successful partial splenectomy was carried out back in the 60s of the last century [36]. Although laparoscopic decapsulation is non-invasive, if it is not performed radically, epidermoid cysts can reoccur in less than 5 months [21]. During the past two decades, many authors describe the advantages of a laparoscopic splenectomy compared to the conventional surgery [44]. Both surgical and medical indications for splenectomy include congenital hematologic diseases; autoimmune disorders; hypersplenism as a result of different conditions (Niemann–Pick disease, Thalassemia, Gaucher disease, etc.); traumatic rupture; lymphomas; cysts; hemangiomas; pancreatic pseudocysts; etc. [36]. In our case, the size of 12 cm of the cyst and lack of inflammation were the main indications for laparoscopic splenectomy as a secure method.

Despite the described benefits of minimally invasive splenectomy, there are several contraindications, which are worth discussing. Coagulopathies, adhesions due to previous surgery and underlying pulmonary and cardiac diseases are among the most common conditions contraindicating laparoscopic TS in the literature [45,46,47].

There are very few comparative studies between TS and PS. Most of them show similar outcomes with low recurrence rates and no complications [48,49].

Total splenectomy is preferred in cases where the cyst is in the hilum of the spleen, and the splenic blood vessels are directly involved.

Novak et al. mentioned that one-quarter of the spleen’s parenchyma is enough to provide the immune function [50]. Thus, partial splenectomy or cystectomy is feasible. It should always be considered in specialized centers, experienced in laparoscopic spleen-preserving surgery.

The definite diagnosis is the histological one. True epithelial cysts are lined by stratified squamous epithelium. However, desquamation is possible in some parts of the cyst wall, and the specimen should be carefully examined [51]. Calcifications are not specific and can be seen both in epithelial and parasitic cysts [51]. Only 10% of the epidermoid spleen cyst has calcifications [52]. Immunohistochemically, cytokeratin is used to confirm the epithelium on the cyst wall. In our case, we used cytokeratin AE1/AE3, which was positive, and WT1 and calretinin, which were negative. Via WT1 and calretinin, we concluded that the cyst is not from mesothelial origin. A flattened epithelium can mimic endothelium. CD-34 can be used to exclude vascular tumors such as hemangiomas and lymphangiomas [34].

4. Conclusions

The splenic epidermoid cyst is a rare condition, usually accidentally diagnosed or due to symptoms of compression. Ultrasound examination is a cheap available screening method. CT or MRI are used to help define the surgical approach. CEA, CA-19-9 and CA-125 could be elevated, and an epidermoid cyst should be suspected. However, the final diagnosis is histological. There is no standardized protocol for surgical treatment, but the laparoscopic splenectomy proved to be fully compliant with the principles of low tissue trauma in pediatric surgery. It leads to a reduced need for post-operative analgesia, better cosmetic results and rapid recovery. In cases of small, peripheral, nonparasitic cysts, a partial splenectomy should always be considered. In our case, the anatomical site and size of the cyst predetermined the contraindications for spleen-preserving surgery.