Comparison of the 7th and 8th version of the AJCC classification system for soft tissue sarcomas of extremities and trunk in patients with localised, intermediate or high-grade disease treated at European tertiary sarcoma centres

Establishment of a staging system for visceral sarcoma

BACKGROUND

Visceral sarcoma is a rare malignancy with a poor prognosis. However, there is no recommended prognostic staging system for the malignant disease.

METHOD

We analyzed the data of patients diagnosed with primary soft tissue sarcoma (STS) of the abdomen and thoracic visceral organs between 2006 and 2017 at our hospital. Prognostic factors (size, tumor grade, and lymph node metastasis) were analyzed in our cohort (n = 203) and the SEER validation cohort (n = 5826).

RESULTS

Tumor size, grade, and lymph node metastasis were important prognostic factors for visceral sarcoma in both our and the SEER cohorts. Based on these prognostic factors, we established a new staging system for visceral sarcoma, by which patients could be stratified into clinically meaningful and non-overlapping stages in both our cohort and the SEER validation series. Moreover, the area under the curve (AUC) value of the staging system for 5-year survival was 0.84 (95% CI: 0.78-0.89) in our series and 0.80 (95% CI: 0.79-0.81) in SEER series, respectively. In addition, compared with the widely used FIGO staging system for female genital sarcoma, the visceral sarcoma staging system could more effectively and reliably stratify patients into four different prognostic groups.

CONCLUSIONS

The visceral sarcoma staging system is applicable for STS of the abdomen and thoracic visceral organs and is better than the current FIGO staging system for female genital sarcoma and should be incorporated into the AJCC Cancer Staging Manual.

Epidemiologic Survey of Myxofibrosarcoma Using Data from the Bone and Soft Tissue Tumor Registry in Japan

BACKGROUND

Myxofibrosarcoma is a common sarcoma among older patients, with locally infiltrative behavior and a predilection for local postoperative recurrence. Some studies have reported the factors affecting prognosis, although only a few have mentioned the previous staging classification systems. This study investigated the clinical overview and prognosis of myxofibrosarcoma to determine the optimal treatment.

METHODS

This retrospective study analyzed the records of 349 patients with myxofibrosarcoma in the nationwide Bone and Soft Tissue Tumor Registry in Japan from 2006 to 2015. Clinical features, treatment options, and patient outcomes were investigated.

RESULTS

Ultimately, 349 patients were identified. The overall survival rates were 93.1% at 2 years and 84.3% at 5 years. A multivariate analysis was performed using the Cox proportional hazards model. The study identified four significant prognostic factors for survival: tumor size, depth, compartment status, and location. The prognostic score was calculated by summing the scores of all the factors. The overall survival rate was 69.3% at 5 years for the patients with prognostic scores of 6 or higher. Conversely, the patients with prognostic scores of 2 or lower had a survival rate of 95.6% at 5 years.

CONCLUSIONS

Among myxofibrosarcomas, those larger than 5 cm, deep-seated, invaded into the external compartment, or in axial body parts were associated with a significantly worse prognosis. Adjuvant radiotherapy and chemotherapy did not contribute significantly to a better prognosis. Previous staging classification systems are impractical for prognosis prediction. Therefore, new classifications are needed. Further research on new treatment methods for patients with a poor prognosis will be crucial in the future.

Robot-assisted tumorectomy for an unusual pelvic retroperitoneal leiomyoma: A case report

RATIONALE

Extrauterine leiomyoma occasionally occurs in rare locations with unusual growth patterns, especially pelvic retroperitoneal leiomyoma, which brings great challenges for surgeons to make a diagnosis. It is essential to distinguish benign from malignant retroperitoneal neoplasms according to the imaging manifestations. Laparotomy and laparoscopy are the common options for pelvic retroperitoneal neoplasms, while they may cause side effects during operation such as secondary damage. Appropriate surgical techniques should be adopted to ensure the complete excision of neoplasms meanwhile preserve the urination, defecation, and sexual function.

PATIENT CONCERNS

A 30-year-old woman was referred to our hospital because of dull pain in the perianal region for 1 month. Laboratory results including tumor markers were all within normal limits. The digital rectal examination revealed a huge and tough mass with smooth mucosa protruding into the rectal cavity from the rear area of rectum.

DIAGNOSIS

Imaging examinations were performed. Contrasted computed tomography (CT) of pelvis showed an enhanced retroperitoneal solid mass in the space between sacrum and rectum, and very close to the levator ani muscle. The mass was about 11.0*8.0 cm in size. Computerized tomography angiography (CTA) showed the distal branches of bilateral internal iliac artery went into the mass. Endoscopic ultrasonography (US) showed the mass compressed the rectum, as well as a clear boundary to the rectal wall. A histopathologic examination confirmed the mass was a pelvic retroperitoneal leiomyoma.

INTERVENTIONS

The patient underwent an operative resection with da Vinci Si surgical system after routine preoperative preparation. Anorectal motility was weekly monitored postoperation. No additional adjuvant therapy was performed.

OUTCOMES

The patient could walk after 1 day and defecate normally on the third day after operation. She was discharged on the seventh postoperative day. No adverse events including pelvic floor hernia or defecation dysfunction occurred in the follow-up period. At 4 weeks follow-up, the patient was pain-free and recovered well.

LESSONS

Although imaging examinations were crucial for retroperitoneal neoplasms, histopathological examination remains the "gold standard" for making a definite diagnosis. This case highlights the possibility of retroperitoneal leiomyoma occurring in a woman of reproductive age and the advantages of robotic surgical system in pelvic retroperitoneal surgeries.