公猪的肿瘤并不常见，睾丸肿瘤则更为罕见。本研究描述了具有生育问题的商业公猪睾丸肿瘤病例系列的病理和免疫组织化学特征。 333 只动物中有 19 只检测到肿瘤（19/333，5.9%）。肉眼观察，13头（13/19，68%）公猪发现肿瘤，6头（6/19，32%）仅通过镜检发现肿瘤。 1头公猪观察到睾丸增大，而其他公猪仅在去除阴囊皮肤或切片睾丸后才观察到肿瘤。组织学上，肿瘤分为精原细胞瘤（16/19，84%）、混合生殖细胞间质肿瘤（2/19，11%）和B细胞淋巴瘤（1/19，5%）。精原细胞瘤有 3 种不同的生长模式：管内（6/16，38%）、弥漫性（4/16，25%）和管内/弥漫性（6/16，38%）。所有肉眼检查不明显的肿瘤均为管内精原细胞瘤。睾内转移2例，睾外转移1例，位于蔓状神经丛。在 1 例精原细胞瘤中，睾丸网也受累。通过免疫组织化学检测，所有管内精原细胞瘤 c-kit、细胞角蛋白和波形蛋白均为阴性。在弥漫性精原细胞瘤中，c-kit和细胞角蛋白也呈阴性，而波形蛋白在某些区域显示颗粒状或核周细胞质标记。 PAX-5 和 CD-3 抗体将淋巴瘤分类为 B 细胞淋巴瘤。这项研究表明，公猪的睾丸肿瘤可能比以前报道的更常见，特别是在进行显微镜检查时。它还表明猪的睾丸肿瘤主要是精原细胞瘤。

Tumors in boars are uncommon, and testicular tumors even rarer. This study describes the pathological and immunohistochemical characteristics of a case series of testicular tumors in commercial boars with fertility problems. Tumors were detected in 19 of 333 animals (19/333, 5.9%). Macroscopically, tumors were observed in 13 (13/19, 68%) boars, while 6 cases (6/19, 32%) were only detected by microscopic examination. Testicular enlargement was observed in 1 boar, while in the others, tumors were only observed after removal of the scrotal skin or after sectioning of the testis. Histologically, tumors were classified as seminomas (16/19, 84%), mixed germ cell-stromal tumors (2/19, 11%), and B-cell lymphoma (1/19, 5%). Seminomas had 3 different growth patterns: intratubular (6/16, 38%), diffuse (4/16, 25%), and intratubular/diffuse (6/16, 38%). All tumors that were not evident on macroscopic examination were intratubular seminomas. Intratesticular metastases were observed in 2 cases and extratesticular metastases, located in the pampiniform plexus, were observed in 1 case. In 1 seminoma, the rete testis was also involved. By immunohistochemistry, all intratubular seminomas were negative for c-kit, cytokeratin, and vimentin. In diffuse seminomas, c-kit and cytokeratin were also negative, while vimentin showed granular or perinuclear cytoplasmic labeling in some areas. PAX-5 and CD-3 antibodies classified the lymphoma as a B-cell lymphoma. This study suggests that testicular tumors in boars may be more common than previously reported, especially when microscopic examination is performed. It also shows that testicular tumors in pigs are predominantly seminomas.