• "Pleomorphic RMS (PRMS) is a very rare subtype of RMS occurring predominantly in the head and neck, genitourinary tract, or in the deep soft tissues of the extremities, almost exclusively in male patient older than 45 years."

• "Pleomorphic RMS is an aggressive sarcoma, arising predominantly in the extremities of adult males usually 45 of older."

• "Pleomorphic RMS, which almost exclusively occurs in the adult population, is located most commonly at the extremities..."

• "PRMS is a very rare but aggressive tumor."

• "Histopathologically, PRMS is composed of large, atypical, spindle-shaped or polygonal pleomorphic rhabdomyoblasts with eccentric nuclei, and abundant eosinophilic cytoplasm."

• "The histological description of pleomorphic RMS is that it is composed of large, atypical, polygonal pleomorphic rhabdomyoblasts with abundant cytoplasm."

目前，对于成人多形型横纹肌肉瘤，尚无全球统一的标准治疗方案。由于其罕见性，治疗策略多参考成人软组织肉瘤的指南或借鉴儿童RMS的治疗经验。主要的治疗手段包括：

1. 手术：广泛完整切除（R0切除）是实现局部控制和改善预后的基石。

2. 化疗：化疗方案存在争议。一些研究表明，采用基于儿童RMS方案的化疗（如VAC方案：长春新碱、放线菌素D、环磷酰胺）可能对某些PRMS患者有效，特别是年轻患者。然而，PRMS对化疗的反应通常不如胚胎型或腺泡型RMS。另一些中心则采用成人软组织肉瘤的化疗方案，如以多柔比星和异环磷酰胺为基础的联合化疗。

3. 放疗：用于手术切缘阳性、有微观残留或无法手术切除的局部病灶，以提高局部控制率。

由于缺乏前瞻性临床试验，治疗选择通常需要在多学科专家团队（肉瘤中心）中根据患者的具体情况进行个体化决策。

相关英文原文：

• From "Pleomorphic rhabdomyosarcoma with an impressive response to chemotherapy: case report and review of the literature":

• "Due to its clinical characteristics, treatment is currently based on the guidelines for adult soft tissue sarcoma therapy."

• "Our case report emphasizes that multiagent systemic therapy according to pediatric protocols should be considered in adult patients with pleomorphic RMS."

• "Treatment consisted of 7 cycles [of VAC regimen]..."

• From "Rhabdomyosarcoma in Adults: New Perspectives on Therapy":

• "There is no standardized treatment described for adults..."

• "Ideally, complete resection with margins greater than 1cm should be performed."

• "Radiotherapy (RT) is an important component of multimodality therapy..."

• "At our center, front-line chemotherapy for adult patients with metastatic RMS are treated with vincristine, doxorubicin, and ifosfamide."

• From "Case of pleomorphic rhabdomyosarcoma...":

• "Ideal surgical management is complete resection with negative microscopic margins."

多形型横纹肌肉瘤的整体预后较差，生存期因疾病分期、治疗方案和患者个体差异而不同。

• 整体生存率：多项研究表明，成人RMS（包括PRMS）的5年总生存率（OS）约为20%-40%。对于PRMS亚型，预后更差。在一项大型法国研究中，PRMS患者的中位总生存期仅为16个月。

• 分期影响：局限期患者的预后明显好于转移期患者。局限期RMS的5年OS约为43%，而晚期（有淋巴结或远处转移）患者的5年OS仅为5%。

• 治疗方案影响：

• 手术：实现R0切除（切缘阴性）的患者生存期显著延长。在一项回顾性分析中，R0切除是改善局限期和晚期RMS患者OS的独立预后因素。

• 化疗：使用基于儿童方案的化疗（如VAC）与改善胚胎型/腺泡型RMS成人患者的生存期相关。对于PRMS，一项研究报告了一例70岁转移性PRMS患者在接受VAC方案化疗后获得了显著且持久的缓解，至报告时16个月无进展。然而，总体上PRMS对化疗的反应有限，化疗对PRMS生存期的确切影响仍需更多研究证实。

• 放疗：辅助放疗也被证明可以改善局限期和晚期RMS患者的OS。

相关英文原文：

• From "Outcome of 449 adult patients with rhabdomyosarcoma: an observational ambispective nationwide study":

• "5-year OS for localized RMS and advanced RMS was 43% and 5%, respectively, (P < 0.0001), and median OS was 51, 33, and 16 months for E-RMS, A-RMS, and P-RMS, respectively, in the retrospective cohort."

• "In a multivariate analysis... independent prognostic factors for OS were A-RMS, R0 resection, and adjuvant radiotherapy (RT). For localized RMS, age and use of pediatric chemotherapy (CT) regimen are independent prognostic factors."

• "For advanced RMS, OS was positively influenced by non-A-RMS histological subtypes (P = 0.009), R0 resection (P = 0.04), and use of RT (P = 0.02)."

• From "Pleomorphic rhabdomyosarcoma with an impressive response to chemotherapy: case report and review of the literature":

• "Sixteen months after primary diagnosis, computed tomography scan shows no signs of tumor progression." (Referring to the patient treated with VAC).

• "The 5-year disease-free survival was 27%." (Quoting the Furlong et al. series of 38 PRMS patients).

• From "Rhabdomyosarcoma in Adults: New Perspectives on Therapy":

• "Pleomorphic RMS... is usually related with poor prognosis... when compared to other adult pleomorphic sarcomas, having less overall survival."

已发生肺转移的PRMS属于晚期疾病，治疗应以全身性控制为首要目标。优先推荐采用基于儿童方案的联合化疗（如VAC方案：长春新碱、放线菌素D、环磷酰胺），以期控制原发灶和转移灶。化疗后需进行影像学再评估：若转移灶显著缩小或稳定，可考虑对原发灶或残留转移灶进行局部巩固治疗（手术或放疗）。不推荐优先进行肺转移灶或原发灶的手术，因为手术无法解决全身播散问题，且可能延误全身治疗的启动。这一策略在Kollar等报告的病例中得到证实：一例70岁转移性PRMS患者首先接受VAC方案化疗，获得显著部分缓解，肺转移灶持续缩小，原发灶随后接受放疗巩固，16个月时无进展。

英文原文支持：

1. Kollar et al. (Pleomorphic rhabdomyosarcoma with an impressive response to chemotherapy):

• “Due to the advanced stage of the disease and the high risk of skin perforation, systemic treatment according to the VAC regimen (vincristine, actinomycin, cyclophosphamide) was initiated immediately.”

• “The radiographic follow-up revealed a continuous response of the lung metastasis and delayed response of the primary tumor.”

• “At the last radiologic follow-up in August 2015, 12 months after initiation of the treatment, no signs of progressive disease at the primary tumor site or the lungs were seen.”

2. Bompas et al. (Outcome of 449 adult patients with rhabdomyosarcoma):

• “For advanced RMS, OS was positively influenced by non-A-RMS histological subtypes, R0 resection, and use of RT.” （提示在晚期患者中，若能达到R0切除或使用放疗，可改善生存，但通常是在全身治疗基础上进行）

• “In the present study, local surgery had a favorable impact on survival even for patients with metastatic RMS which is consistent with the MSKCC and French pediatric experience. These observations could change this approach, and advanced disease surgery should be debated whenever possible.” （指出对于转移性RMS，局部手术可能有益，但需在多学科讨论中决定，并未否定全身治疗优先）

3. Ruiz-Mesa et al. (Rhabdomyosarcoma in Adults: New Perspectives on Therapy):

• “Rhabdomyosarcoma patients with either metastatic or primary disease should be considered for multidisciplinary treatments including chemotherapy, radiation, and surgery.” （强调多学科综合治疗，但顺序未明确，结合上下文通常先化疗）