Mills S E, Walker A N, Stallings R G, Allen M S
Arch Pathol Lab Med. 1984 Sep;108(9):737-40.
Retrorectal cystic hamartomas (RCHs) are uncommon lesions of controversial pathogenesis that arise in the presacrococcygeal space. We describe the clinicopathologic features of RCHs from three adult patients. Two were asymptomatic women; the third was a man who had a pelvic abscess. All three specimens were multiloculated cysts lined by squamous, transitional, and glandular epithelium. Poorly organized collections of smooth muscle were present in the surrounding connective tissue, but no well-formed smooth-muscle coat was seen. Although RCHs possess elements of three germ-cell layers, their histologic features are similar to those of the embryonic tailgut. The male patient also had a perirenal mass that was grossly and histologically identical to the RCH. The associated kidney was malrotated. A portion of the embryonic tailgut may have been pulled cephalad by the developing kidney, inhibiting its rotation. Clinicopathologic features distinguish RCH from other retrorectal cystic lesions, including teratoma, dermoid, epidermal cyst, rectal duplication, anal duplication, and anal gland cyst.
直肠后囊性错构瘤（RCHs）是发生于骶前尾骨前间隙的病变，发病机制存在争议，较为罕见。我们描述了3例成年患者RCHs的临床病理特征。2例为无症状女性，第3例为患有盆腔脓肿的男性。所有3个标本均为多房性囊肿，内衬鳞状上皮、移行上皮和腺上皮。周围结缔组织中有排列紊乱的平滑肌束，但未见完整的平滑肌层。虽然RCHs具有三个胚层的成分，但其组织学特征与胚胎尾肠相似。该男性患者还患有一个肾周肿物，大体和组织学表现均与RCH相同。相关肾脏旋转不良。发育中的肾脏可能将部分胚胎尾肠牵拉向上，抑制了其旋转。临床病理特征可将RCH与其他直肠后囊性病变相鉴别，包括畸胎瘤、皮样囊肿、表皮样囊肿、直肠重复畸形、肛门重复畸形和肛门腺囊肿。
