Unicentric Castleman’s Disease Presenting as Retroperitoneal Pelvic Lymph Node in Young Female—Laparoscopic Excision: A Case Report

Unicentric Castleman’s disease (UCD) is localized lymphoproliferative disease and has favourable prognosis. Surgery offers complete cure of unicentric Castleman disease. Radiotherapy offers either complete response or variable clinical response and cure in selected patients. The present case report is of a young unmarried obese girl presented with pain in right iliac fossa for 2 months. On pelvic ultrasound and MRI performed for diagnosis only single enlarged right external iliac lymph node was the positive finding. The CT scan guided biopsy was performed and the histopathological finding was lymphoid lesion-reactive lymphoid hyperplasia is favoured over Hodgkin’s lymphoma. Successful laparoscopic complete excisional surgery was performed for this single enlarged external iliac lymph node. The final histopathological report of the lymph node removed was unicentric Castleman’s disease, hyaline vascular type. This is the 16th such reported case of pelvic retroperitoneal UCD of hyaline vascular type treated by surgical excision, and 3rd case treated by Laparoscopic excisional surgery. By now at the time of reporting this case 4 months of follow up has been completed and patient does not have any symptom nor not show any sign of residual disease locally on transabdominal ultrasound examination and whole-body PET CT scan is also normal.


Case Report
This is a case report of 24 yrs. Young unmarried obese female presented with lower abdominal pain and generalized weakness for 2 months.
Before being referred to us she was investigated at another hospital where MRI was performed. The report of MRI was uterus and both adnexal structures were normal, a lobulated solid lesion in right iliac fossa of 73 × 49 × 35 mm, regular well circumscribed with areas of calcification without necrosis within suspicion of soft tissue neoplastic lesion (Figures 1-6).      Based on MRI report CT guided biopsy was performed in the same hospital which reported as lymphoid lesion-reactive lymphoid hyperplasia is favoured over Hodgkin's lymphoma (Figure 7).
She was referred for laparoscopic excisional biopsy with a suspicion of lymphoid hyperplastic disease.
When she presented to us her vital signs were normal (Pulse: 90/min, B.P: 120/70 mmhg, SpO 2 : 99%) and had a BMI of 37. There were no symptoms related to bowel or bladder. On abdominal palpation she was obese and a firm tender fixed mass was palpable in right iliac fossa with ill-defined margins. We

Discussion
Castleman's disease (CD) is a rare benign lymphoproliferative disorder.  [6]. Ironically in all cases of laparoscopic surgery reported the size of the mass between 5 -7 cm [3] [4]. In the present case, the patient had pelvic and lower abdominal pain because of the pressure effect of large lymph node. Laparoscopic excision of unicentric Castleman's has been reported for other sites in peritoneal cavity [7]. Castleman's disease should be included as one of the differential diagnosis points in female adnexal mass. The other mass in this area can be lymphoma, sarcoma, metastasis, neural tumour, and granulomatous disease [8]. The mass related to ovary at this site can be dermoid cyst, endometriotic cyst or ovarian abscess.
There are three histological variants of Castleman's disease described classic hyaline-vascular form usually found in UCD, the plasma cell type more seen in MCD (Multicentric Castleman's disease) type (9% to 24% of UCD) and the plasmablastic cells or plasma cell CD more commonly seen in patients with MCD with HHV-8 infection. POEMS syndrome (Polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes) and TAFRO syndrome (thrombocytopenia, anasarca, reticulin fibrosis of the bone marrow, renal dysfunction, and organomegaly) can be associated with MCD [9].
The histopathology of the excised mass was identical as angio follicular lym- The consistency of the mass expressed was rubbery firm in the previous case reports while as in the present case it was firm too hard.
Surgical approach was most commonly applied for UCD at different locations and these patients had overall high survival rate. If the excisional surgery is unsuccessful the mortality remains high [3] [11].
There is a risk of excessive bleeding in surgery as the mass is vascular. In the present case, the estimated intraoperative blood loss was 10cc.
As the lesions are vascular some authors have suggested pre-operative vascular embolization of the feeding vessels especially presence at odd locations [12].
The lesions in case of UCD are larger as compared to MCD [13]. In the present case also the lesion was large as 73 × 49 mm.
In incompletely excised mass with recurrence of symptoms, the patient will require treatment by chemotherapy [3]. This means a close follow up and additional treatment is required where the mass was not completely removed.

Conclusions
We now know more about the disease profile and pathogenesis of CD since its first diagnosis about 66 years back. MCD is less common than UCD. A high index of suspicion is required to diagnose these conditions as it is a rare disease.
There are a limited number of retroperitoneal UCD reported in female pelvis.
Other retroperitoneal mass in females can be ovarian tumor, endometriomas, In case of doubt in diagnosis excisional biopsy should be performed as it was done in this case. Castleman's disease should be included as differential diagnosis in female with pelvic mass.
Excisional surgery gives a good prognosis and survival in UCD. Considering the existing published data for the management on Unicentric Castleman's disease surgical resection appears to be the most effective treatment for resectable lesions. Laparoscopic excision is best suited for retroperitoneal pelvic unicentric Castleman's disease.