Abdominal masses are a reason for frequent consultation in surgery. They hide behind several diseases, both benign and malignant.
We report a study on abdominal masses, regardless of the etiology and age group in a new hospital, of reference in Niger, which has not fully completed the installation of its imaging devices. We reported a frequency of 6.7% abdominal mass among all the overall activities of the HGR digestive surgery department during the study period. Our results are higher than those reported by Okoko A-R. et al (4) in Brazzaville in 2012 who had worked only on children, with 1.3%. We note a female predominance with 75.5% and a sex ratio at 0.32. This female predominance was reported by Akkoca M. et al (5) in Turkey in 2017 (60%), Mahamoud G. et al (6) in Morocco in 2010 (54.1%). The average age of our patients was 41.8 years 14.2 with extremes of 10 and 69 years; very few studies had been reported on all ages like ours; Children’s studies are generally found in the literature (7); The prevalence of abdominal masses by age was little discussed. But classically, abdominal masses of neoplastic origin are rare in the first year of life, but very common between the ages of 1 and 6 (4). Abdominal pain was the main indicator in most of our patients (84.9%). Lower rates were found by Akkoca M and al, and Mahamoud G and al., respectively 61%, 57.5% of cases (5, 6). In the older patient, the primary mode of abdominal mass disclosure is incidental discovery by a parent (7).
In our study, the physical examination found palpable abdominal mass in 77.3% of cases, although 17% of patients were obese. The consistency of the mass was hard and irregular in 47.5% of cases, painful sensitivity in 62.5% of cases, and the mass was fixed relative to the deep plane in 60% of cases. Akkoca M. et al (5) in a series of 43 cases in Turkey in 2017 had recovered abdominal mass on physical examination in 62.2% of cases. This difference in frequency could be justified because our study focused only on large abdominal masses, therefore accessible for examination.
Abdominal pelvic ultrasound is currently the reference technique for abdominal mass diagnosis. It allows the topographical diagnosis of the mass, to attach it to an organ, to determine with precision the tumor volume, and to define its solid or liquid character (8). In an American journal of the literature published in 2019, the authors stated that 88–91% of the ultrasound was accurate in determining the original organ and 77–81% in diagnosing the underlying pathology (9). In our study, ultrasound was performed in 100% of cases. It specified the location of the mass and the original organ in 75.47% of cases (uterine myomas, ovarian cyst, renal tumors, etc.) and contributed to the realization of ultrasound biopsy punctures in 4 cases. Our results are similar to those of Kathryn J.F et al (9) in the USA in 2019 who reported ultrasound achievement rates in 100% of their series. In case of clinical suspicion of abdominal mass, the ultrasound requested in 1st intension is justified (strong professional agreement), and it is a first-line examination requested in the literature, it is less expensive, non-invasive and very well supported by the patient (8). However, its performance may decrease because it is an operator-dependent examination, in addition to in the context of abdominal emergencies, the sensitivity of the ultrasound is often much lower than that of the scanner which will be preferred in most indications (10). On the other hand, as one author pointed out, “the effectiveness of the ultrasound depends on the relevance of the application” (2) means that the better the clinical information on the application is reported, the better it is to guide the operator.
Abdominal CT is the key examination of abdominal mass balance. It brings valuable elements in the localization by anatomical compartments, organ localization, characterization and evaluation of the extension of these masses (2). Over the past 15 years, it has undergone a rapid technological evolution, moving from sequential to spiral, mono- and multidetector modes. This evolution currently allows to investigate an abdomen in a few seconds with a spatial resolution less than 1 mm allowing routinely multiplanar reconstructions of quality equal to the initial scans (10). In our series, CT was performed in 52.8% of cases. It had contributed to the etiological diagnosis in 89.29% of cases. Our results are lower than those found by Akkoca M. and al (5) in Turkey in 2017 which had reported 62.2%. The low achievement of the scanner compared to the ultrasound could be explained by the high cost of this examination, especially in our context where most patients do not have social security and by the fact that it is not indicated in first intention, especially in young patients because of its irradiance (often need injection of iodized contrast agent).
The etiologies of the abdominal masses were diverse, we had reported three cases where the scanner could not establish a diagnosis of pre-operative abdominal mass. The etiologies of the abdominal masses were diverse, we had reported three cases where the scanner could not establish a diagnosis of pre-operative abdominal mass. The diagnosis of this intra-abdominal soft tissue sarcoma could not be established pre-operative by CT in our study. MRI remains the reference exam for the local Soft Tissue Sarcoma because it has excellent tissue contrast (11). The tumor was compressing both ureters and the possibility of a neoadjuvant treatment such as radiotherapy in Niger was almost impossible at a time when the country did not have it. It was necessary to request a medical evacuation outside that would have lasted several months. Exploratory laparotomy was indicated and R0 resection could not be obtained due to tumor invasion of the left ureter. Despite the adjuvant chemotherapy, the recurrence had been very rapid and overwhelming. The 2nd case involved a tumour occupying the entire abdominal cavity, and it is reported that the scanner is ineffective in determining the origin of the organ in these cases of giant tumor of the abdomen (interest of multiplanar reconstruction) (2). And per operation, it was a large poly myomatous uterus and necropolis. The last case concerned a suspicion of a mesenteric tumor at the injected scanner and the discovery of a peritoneal carcinosis from an ovarian tumor per operative was accidental. Diagnosis of peritoneal carcinosis is easy in diffuse and macronodular forms with ascites. Rough shapes are difficult to diagnose. Imaging peritoneal carcinoses (12) remains first and foremost a technical challenge in radiology: because it requires high spatial resolution (especially in small lesions) and high contrast resolution (nodules have low spontaneous contrast with no significant enhancement) and finally there is a minimization of motion artifacts due to the contact of the handles that are moving. Secondly, it is a radiological challenge because peritoneal carcinoses have low reproducibility, and most are seen only in surgery. However, the scanner is still the reference tool, but it has limited sensitivity per organ site, especially at the pelvic level (13). The FDG-PET scan and/or diffusion MRI is recommended (12). However, our hospital did not have an MRI at the time of the study and the entire country does not have a Pet scan. In our study, we found a more significant frequency of uterine myomas (35.8%), followed by ovarian cysts in 11.3% of cases and ovarian tumors in 9.7% of cases. This may be related to the female predominance (75.5%) and young age (41 years of average age) of our study population. As reported by most authors, uterine myomas and ovarian cysts represent the main etiologies of abdominal-pelvic masses in black women during genital activity and pre-menopausal period (13, 14). The choice of therapeutic approach depends on the histological type, mass extension and age of the patient (15). For our patients, two methods of treatment have been used: chemotherapy and surgery, radiation therapy not yet available in Niger. These methods were in some cases well-suited and in others adapted to the work context.
Surgery was the main therapeutic remedy (100%). We reported an exceptional case of total hysterectomy in a 32-year-old nulligeste patient with a large uterine myoma in necropsy and having occupied almost the entire abdominal cavity. He was responsible for severe anemia with vomiting (by gastric compression). The hysterectomy piece (retaining an ovary), measured 29mmx23m height. n our series, the evolution was favorable for the majority of patients. Nevertheless, a 5.6% mortality rate was reported for all abdominal masses. All deceased patients had malignant tumours. Most of these patients had consulted at an advanced stage of their illnesses. Our results are superior to those found by Akkoca M and al (5) which reported a mortality rate of 4.4%.