Abstract 5799: Epidemiology and prognostic factors of primary paratesticular lymphoma (PPTL): A pooled case-series since 1980

Abstract

Abstract PPTL involving the spermatic cord &/or epididymis and sparing the testicular parenchyma is an extremely rare and heterogeneous disease. It doesn't exceed 1.5-2% of all tumors of the spermatic cord. Old cases indicated that PPTL was highly lethal. Many significant changes in classification and treatment have occurred since these reports were published. This retrospective epidemiologic review was conducted to update our knowledge of PPTL using more recent cases that reflect the current state of medicine. This study included all published cases of PPTL in English between 1980-2019 attempting to explore the demographic characteristics, presentation and metastases patterns, types of therapies, and survival of patients with PPTL. The Kaplan-Meier method was used to estimate survival. Log-rank test and multivariate Cox regression models were used to assess the influence of demographic and clinical factors on survival. A total of 34 (27 spermatic cord, 6 epididymis, 1 seminal vesicle) patients with PPTL were identified. The median age was 65 years. A sharp increase in the reported PPTL cases aged 50 and above was noted, peaking within the 72-82 year age-bracket. Diffuse Large B- Cell Lymphoma (DLBCL) was the most prevalent histology (85%). Other types consisted of 1 PEL-like DLBCL, 2 Follicular lymphomas, 1 Marginal Zone Lymphoma, and 1 Intravascular T-cell Lymphoma. The majority presented with Ann-Arbor stage I (65%), followed by II (18%), IV (15%) and III (3%). Only one patient had B-symptoms. All cases presented with growing painless scrotal masses except 2 patients who reported pain including one with bilateral scrotal masses. The average tumor size was 6cm (3-8.5cm). When presenting with stage IV, the majority had involvement of the abdominopelvic and cervical/supraclavicular lymph nodes with additional prostate involvement in one patient and tonsillar involvement in another. All the patients underwent orchiectomy for diagnostic purposes followed by chemotherapy except one who was treated with primary radiation alone. Twenty-eight percent received radiation and only 12% received intrathecal chemotherapy. Median overall survival of the whole group was 12 months. Univariate analysis revealed that PPTL of the epididymis and cases reported after 1990 had significantly better survival. Early stages I&II was of borderline significance. While Age <50 seemed to have better survival, it did not reach statistical significance. However, in multivariate analysis, stage, reporting year, and age significantly impacted the survival of this cohort. This retrospective study presents an updated epidemiologic descriptive data and provides prognostic factors from a relatively recent PPTL cohort. Moreover, it clarifies the perception of the lethality of the disease as PPTL seems to have a similar median overall survival to testicular lymphoma. Citation Format: Philip A. Haddad. Epidemiology and prognostic factors of primary paratesticular lymphoma (PPTL): A pooled case-series since 1980 [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 5799.