The stomach is the most common site of gastrointestinal lymphoma and accounts for fewer than 5% of primary gastric tumors. Gastric lymphomas can be primary or secondary to systemic lymphomas. Primary gastric lymphomas (PGL) are defined as the involvement of the stomach mainly without systemic disease or those with gastrointestinal symptoms on presentation. This study reports a single-center experience with PGL simulating carcinoma with analysis of clinicopathological presentations and lines of treatment. A retrospective study was performed between September 2006 and May 2021. The study was carried out in the Oncology Center, Mansoura University, Mansoura, Egypt. The study included 66 PGL patients who were F/M (50%/50%) with a mean age of 58.26±12.8 years. Twenty-nine patients underwent gastrectomy, and 37 patients were treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone (R-CHOP). The patients' clinical, endoscopic, and pathologic data were analyzed. Demonstration of the clinicopathological features of PGL patients and assessment of the role of surgery in PGL in the era of rituximab. The patients' presentations were dyspepsia (65.2%), vomiting (21.2%), gastrointestinal bleeding (10.6%), and dysphagia (3%). The endoscopic appearances were ulcerating lesions (60.6%), exophytic masses (24.2%), hypertrophic lesions (10.6%), and hyperemic lesions (4.5%). The median tumor size was 4.9 cm (range 1.5-17 cm). The tumor locations were the lower part of the stomach (n=40 cases), the middle part (n=11 cases), the upper part (n=14 cases), and diffuse (n=1 case). Patients were classified by Lugano staging into stage I (18.2%), stage II (53%), stage IIE (16.7%), and stage IV (12.1%). Twenty-nine patients underwent surgical exploration in the form of distal gastrectomy (79.3%), total gastrectomy (13.8%), and gastro-jejunostomy (6.9%). Indications of surgery were PGL mimicking carcinoma in 25 patients and 4 patients with gastric outlet obstruction. Pathologically, PGL was diffuse large B-cell lymphoma (DLBCL) (87.9%), mucosa-associated lymphoid tissue lymphoma (7.6%), follicular lymphoma (3%), and T-cell-rich non-Hodgkin lymphoma (1.5%). The median overall survival was 27.5 months (2-146 months). PGL is simulating gastric carcinoma in clinical and radiological presentations, and surgery may be a therapeutic option, especially in DLBCL.