Article Type : Case Report
Authors : Bahrou N, EL Hamzaoui J, Ed-dahby O, El Abidine Khedid YZ, Echarrab E, Elounani M, El Faricha El Hassan A and El Absi M
Keywords : Neurofibroma; Presacral; Benign tumor; Case report; General surgery
Presacral neurofibroma is a rare benign
tumour that originates from nerve sheaths, these masses pose real challenges in
both diagnosis and treatment due to its infrequency and unique location. In our
report, we discuss the case of a 36-year-old woman experiencing lumbosciatic
pain, whose presacral neurofibroma was identified through preoperative imaging
and confirmed via histopathological analysis. Surgical removal of the tumour
was successful, resulting in positive postoperative outcomes. This case
emphasizes the importance of utilizing preoperative imaging techniques and
surgical expertise to effectively manage presacral neurofibromas. Furthermore,
we provide a comprehensive overview of existing literature, discussing various
diagnostic methods, treatment options, and potential complications associated
with this uncommon tumour.
Neurofibromas are non-encapsulated neurogenic tumors
originating from nerve sheaths, they account for 5% of benign tumors in soft
tissues. These ectodermal neoplasms are characterized by their exceptional
rarity, both in terms of occurrence and specific anatomical localization.
Predominantly found in the thoracic region, followed by the cervical and lumbar
regions, merely 1 to 5% of neurofibromas manifest in the presacral region [1].
The intricacies of this anatomical region necessitate a comprehensive,
multidisciplinary approach for optimal management, particularly within the
framework of a university hospital [2,3]. Typically exhibiting paucisymptomatic
or asymptomatic characteristics, these masses often present diagnostic
challenges with inconclusive clinical examinations. Diagnosis frequently occurs
at an advanced stage of development. Recognizing the anatomical intricacies,
preoperative imaging assumes paramount significance in establishing a
definitive diagnosis and formulating an effective therapeutic strategy [2,3].
We herein present a case study detailing a pelvic mass identified as a
presacral neurofibroma.
A 36-year-old female patient with no notable medical history presented with progressively worsening lumbosciatic pain. Lumbar MRI revealed a small paramedian disc herniation at L5-S1, accompanied by a hypodense tissue enlargement of the L5 root extending over 65mm (Figure 1,2). Subsequently, the patient underwent posterior surgery for mass reduction, and histopathological analysis confirmed a neurofibroma through immunohistochemical examination. A follow-up angioscan, conducted 10 months later, identified a lesion at the level of the first sacral foramen measuring 35*38 mm, compressing the psoas muscle, iliac artery, and anterior and posterior trunks (Figure 3). Opting for an anterior approach, a midline incision was made, revealing a small mass below the external iliac pedicle. Following peritoneal opening and dissection of vital structures (urethra, external and internal iliac pedicle) (Figure4), the encapsulated mass was visualized and completely resected, ensuring hemostasis (Figure 5). Immediate postoperative outcomes revealed minimal monoparesis of the right lower limb, spontaneously regressing. The patient was discharged on the third postoperative day. Histopathological examination revealed a fusocellular proliferation characterized by interwoven bundles of spindle cells with dark and undulating nuclei, interspersed with collagen bands and devoid of mitotic activity (Figures 6,7).
Figure 1: MRI Axial view.
Figure
2:
MRI sagittal view. ?
Figure 3: Angioscan axial view.
Figure
4: Peroperative
view of the mass adjacent to the external iliac pedicle.
Figure
5:
Peroperative view of the surgical specimen.
Figure
6:
Neurofibroma: fusocellular proliferation HEX10.
Figure 7: Presacral neurofibroma : fusocellular proliferation
characterized by interwoven bundles of spindle cells with dark and undulating
nuclei, interspersed with collagen bands HEX40.
Immunohistochemical staining with anti-PS 100
antibodies exhibited diffuse marking on the tumour cells, indicative of a
neurofibroma diagnosis. Short and long-term follow-up through repeated clinical
examinations showed no signs of recurrence or complications.
Retroperitoneal masses encompass a variety of
entities, ranging from neural tumors like schwannomas and neurofibromas, to
fatty tissue lesions such as lipomas and liposarcomas, along with desmoids,
lymphomas, and vascular tumors like hemangiopericytomas and angiosarcomas [4].
Neurofibromas, which are rare ectodermal tumors, exceptionally involve the
retroperitoneum. They may appear as solitary growths or, more commonly, as
multiple lesions associated with conditions like neurofibromatosis type 1 (NF1)
or Von Recklinghausen's disease, which is the case with our patient [5]. These
tumors tend to grow slowly, extending into the retroperitoneum, presacral
space, and soft tissues. In most cases, they do not degenerate, except in 4 to
11% of instances linked to NF1 [2]. Our case is unique due to its rare
presacral localization [6]. These tumors often manifest at a young age [1] and
remain largely asymptomatic for an extended duration until reaching
considerable sizes [7]. This growth can lead to symptoms such as a sensation of
heaviness, digestive issues, and urinary symptoms, including hematuria,
dysuria, pollakiuria, and even renal colic. Additionally, these masses can be
complicated by a massive retroperitoneal hematoma. Preoperative imaging is
essential to establish the diagnosis. During ultrasound examination,
neurofibromas appear as well-defined masses, hypoechoic and homogeneous, with
posterior enhancement [8]. Computed tomography (CT) assesses the tumor's
extension to adjacent structures, particularly the sacral plexus, but may not
always differentiate between giant neurofibromas and neurofibrosarcomas.
Magnetic resonance imaging (MRI) stands out as the most effective modality,
providing precise details about the tumor's location and its relationships with
neighboring structures. In T1-weighted images, its intensity is slightly higher
than that of muscle, appearing hyperintense in T2. Following gadolinium
injection, contrast enhancement is heterogeneous, with a slight central
hypointensity in T1 [9].
Performing a parietal biopsy is not recommended by
some authors, as it often yields inconclusive results and poses risks of
hemorrhage, infection, and tumor dissemination [10]. Managing these types of
tumors requires a multidisciplinary team comprising visceral, orthopedic, and
neurosurgeons [12]. The standard treatment involves a carcinological surgical
excision with negative margins, emphasizing the preservation of adjacent
vascular, nervous, visceral, and bone structures. The choice of the surgical
approach depends on the degree of intra-pelvic and intra-sacral development.
Specifically, an anterior approach is favored for tumors with a significant
presacral component, while a posterior approach is suitable for intra-sacral or
intra-dural components. Occasionally, a combined sacral and abdominal approach
may be employed, as seen in our patient's case [12]. This excision demands a
certain level of surgical expertise to avoid severe complications, including
injuries to the presacral venous plexus leading to hemorrhage, or damage to the
rectum or sacral nerves [13]. However, if the tumor invades adjacent
structures, the excision may be extended to achieve negative margins, albeit at
the cost of neurosensory deficits [11]. In histopathology, a neurofibroma may
present polymorphic cells, including Schwann cells, perineural cells, and
fibroblasts contained within a mucopolysaccharide matrix. It infiltrates
between the nerve fascicles along its trajectory, making its resection
potentially difficult and risky. Immunohistochemical analysis reveals that
neurofibroma cells exhibit weak reactivity with the S-100 protein, in contrast
to schwannomas, where proliferation exclusively consists of Schwann cells, and
positive S-100 immunostaining occurs within the endoneurium of a nerve fascicle
[11]. As for radiotherapy, it is generally discouraged for benign tumours due
to its potential oncogenic risks [12].
Presacral neurofibroma is a rare benign tumour that
often progresses asymptomatically until it reaches significant sizes.
Preoperative imaging aids in diagnosing the condition, mapping the lesion, and
planning a surgical strategy. The preferred treatment is complete surgical
excision, requiring surgical expertise to prevent major complications.
None
The data that support the findings of this study are
available from the corresponding author upon reasonable request.
Consent
of publication
The patient consented to use her data for scientific
study and publication purposes.
Funding
The authors have no source of funding or financial
support except themselves.
Competing
interests
The authors have no conflicts of interest and source
of funding. The subject of study had no commercial interest, no financial or
material support.
Ethics
statement
All Authors declare no conflict of interest.