Large B cell lymphoma presenting as an adnexal mass in an HIV positive patient: a case report

We present a 34-year-old HIV positive woman who presented with a 2-month history of abdominal pain, abdominal distension, night sweats and fever. She had a firm, immobile and irregular abdominopelvic mass of about 30 weeks uterine size. Investigations showed a haemoglobin of 6.5g/dl, (NR 12-14) cancer antigen 125 of 44U/ml (NR 0-35), serum beta human chorionic gonadotropin (HCG) of 0.258mIU/ml (NR 0-5) and alpha fetoprotein of 7ng/ml (NR <10). Her CD4 count was 63cells/mm3. At laparotomy there was a left ovarian mass and the rest of the abdomen and omentum looked grossly normal, leading to the conclusion that the primary was in the ovaries. A total abdominal hysterectomy, bilateral adnexectomy and infracolic omentectomy were done. Sigmoidectomy and Hartmann's procedure were also performed. Histology of the specimens showed a large B cell lymphoma. She has since been commenced on chemotherapy and antiretroviral therapy and has been doing well.


Introduction
We report a rare case of non-Hodgkin's lymphoma that presented to us as an adnexal mass in a 34-year-old woman, recently diagnosed of HIV. The presence of a large tumor involving both ovaries with insignificant disease elsewhere in the abdomen and pelvis lead us to the conclusion that the primary was in the ovaries. Primary Ovarian Non-Hodgkin's Lymphoma (PONHL) is very rare because the ovary lacks lymphatics. PONHL can however arise from lymphocytes, surrounding blood vessels and the corpus luteum [1]. If malignancy is suspected, women with ovarian tumors have to be subjected to surgical exploration. This means, surgical treatment and morbidity associated with it is unavoidable in most women with ovarian non-Hodgkin's lymphoma. These patients would be better managed with chemotherapy, radiotherapy or immunotherapy [2,3]. Surgery plays a minor role in selected patients with non-Hodgkin's lymphoma [4].
Nodal non-Hodgkin's lymphoma has been associated with HIV infection. In sub-Saharan Africa where HIV is highly endemic, clinicians should consider the diagnosis of PONHL in women who present with adnexal mass in the background of an HIV infection.

Discussion
Primary Ovarian Non-Hodgkin's Lymphoma (PONHL) is very rare because the ovary lacks lymphatic tissue. It has been suggested that the PONHL arises from lymphocytes in the ovaries, surrounding blood vessels and the corpus luteum [1]. The pathology of PONHL is usually diffuse large B-cell lymphoma, which was the case in our patient. lymphadenopathy seen on chest X-ray, but clinically, these lesions were small and most likely metastatic disease from the ovaries. There was no histological confirmation of these chest lesions.
The patient was managed as a case of ovarian malignancy with optimal cytoreductive surgery. Due to the rarity of ovarian lymphoma, surgery was done using the usual approach for ovarian malignancy. If it was possible to confirm the lymphoma before surgery, then surgery would not be the primary treatment. Most patients with ovarian lymphoma would have to be subjected to the morbidity associated with surgery as a result of this uncertainty before surgery. There are no radiological features differentiating Non-Hodgkin's Lymphoma (NHL) from other ovarian malignancies. About 40-70% of PONHL are bilateral [6]. In a series, bilaterality, homogeneity, absence of ascites and tumour almost always >5cm at the time of diagnosis are features that were associated with primary ovarian lymphoma [7]. In our case, we did not have access to computerized tomography scan or magnetic resonance imaging scan for better imaging, but current guidelines recommend surgery as first line in the evaluation of an adnexal or ovarian mass suspected to be malignant.
There are no controlled trials to guide the management of PONHL due to the rarity of disease. Treatment is based on standard of care for nodal NHL and case reports and series. Chemotherapy is the primary mode of treatment, with cyclophosphamide, doxorubicin and vincristine (CHOP) being the preferred regimen. Other treatment modalities include biological therapy with rituximab, radiotherapy and stem cell transplantation. Survival ranges widely between 0-36% less than 3 years post therapy. Compared with nodal lymphomas, ovarian lymphomas tend to have poorer outcomes due to late diagnoses, a problem commonly seen with other types of ovarian malignancy [8].
Emergency surgery is recommended for acute abdomen either due to haemorrhage into the tumour, torsion or for intestinal obstruction which is mostly palliative [4]. There are questions of whether surgery increases morbidity or mortality, but there is paucity of data due to the rarity of PONHL. Current evidence points to late presentation due to non-specificity of symptoms, late diagnosis and tumour histological type and grade as poor prognostic factors [8]. Bangera et al. described a case of a patient with HIV who had PONHL.
She had been managed as an emergency and had a laparotomy for intraperitoneal bleed. A highly friable right ovarian mass was found and hysterectomy and bilateral salpingoophorectomy was done.
Patient came back with a recurrence day 17 post operatively and she refused further treatment [9]. The incidence of NHL in patients with HIV infection greatly exceeds that of the general population. This risk is related to the transforming effects of the retrovirus, the immunosuppresion and cytokine dysregulation that results from the disease and opportunistic infections with other lymphotropic viruses [10]. These patients usually present with advanced stage bulky disease and typically involve extranodal sites. Our patient was diagnosed with HIV of which she was started on HAART soon after her first chemotherapy cycle.

Conclusion
Ovarian non-Hodgkin's lymphoma should always be considered in women who are HIV positive presenting with adnexal masses.
Research needs to be done to enable histological confirmation using less invasive techniques in patients who are HIV positive and therefore at significant risk of having ovarian non-Hodgkin's lymphoma. This will go a long way in avoiding surgery and its associated morbidity in these patients who usually do better with other forms of treatment.