NHÂN CA SARCOMA TÚI MẬT TẠI MEDIC (CA 243)

DISCUSSION

Sarcomas of the gallbladder are rare and represent  about 1.5% of all malignant gallbladder diseases. A variety of tumor types have been described including leiomyosarcoma, rhabdomyosarcoma, angiomyosarcoma, Kaposi’s sarcoma, malignant fibrous histiyocytoma, and synovial sarcoma [2]. Leiomyosarcoma of the gallbladder is an especially rare malignant tumor. By 1984, 105 cases of primary sarcomas of the gallbladder had been reported, with primary leiomyosarcomas accounting for 7% of them [3].

The diagnoses were established in accordance with the new World Health Organization classifications for soft tissue tumors and the most recent soft tissue criteria published. Leiomyosarcoma is defined as a malignant tumor composed of cells showing distinct smooth muscle features. In the macroscopy, leiomyosarcoma typically forms a fleshy mass, with colors varying from grey to white to tan. Large examples often display hemorrhage, necrosis or a cystic change. The typical histopathologic pattern of leiomyosarcoma is that of intersecting, sharply marginated groups of spindle cells. In the immunophenotype, desmin, h-caldesmon, and SMA were positive in a great majority of leiomyosarcomas. None of these are absolutely specific to smooth muscle and positivity for two of these markers were more supportive of leiomyosarcoma than positivity for one alone. Immunostains may be focally positive on CD34, epithelial membrane antigen (EMA), keratin and S100. A diagnosis should be made on the appropriate morphologic features, not only on the immunostains. In this case, immunopositive staining was strong for SMA and vimentin but the typical histopathologic pattern of leiomyosarcoma had appeared in the hematoxylin and eosin stain. Therefore other types of the sarcoma were excluded from the diagnosis.

Leiomyosarcoma is more frequent in women between the ages of 50 and 75 years and usually has a poor  prognosis. The presence of gallstones are invariable and the symptoms presented are those of chronic cholecystitis [4]. Histopathologically, the majority of these tumors are high grade and display an epithelioid morphology; but cases with features of well-differentiated leiomyosarcoma have been described.

According to the National Comprehensive Cancer Network clinical practice guideline in oncology ver. I. 2011, patients with a resectable intraabdominal sarcoma should undergo immediate surgical treatment with a grossly negative margin and and possible interoperative radiation therapy. The postoperative margin status was the most important factor contributing to long-term disease free survival [5]. Postoperative treatment options were dependent on the surgical outcomes and clinical, or pathological finding following surgery. Postoperative radiation therapy should be considered in patients with pathological findings of high grade disease following a negative margin resection (R0 resection) or for microscopic positive margins (R1 resection). For patients with unresectable or disseminated recurrences, preoperative RT and/or chemotherapy should be considered after a biopsy. Combination regimens with activity in soft tissue sarcoma include AD (doxorubicin, dacarbazine), AIM (doxorubicin, ifosfamide, mesna), MAID, and so on [6,7].

The single agents include dacarbazine, doxorubicin, epirubicin, gemcitabine, ifosfamide, liposomal doxorubicin and temozolomide [8,9].

The prognosis of sarcoma and leiomyosarcomas of the gallbladder is dismal, the five year survival rate being less than 5%. This is due to the fact that at the time of the diagnosis or surgery. Almost 75% of cases involve the liver [10]. 

Our patient was also diagnosed at an advanced stage, but he had no distant organ metastasis. Because R0 resection is expected in this case, an aggressive surgical approach was attempted. However, soon after, multiple liver metastasis and peritoneal seeding metastasis were detected in post-operative evaluations. Therefore additional aggressive multimodality treatments such as surgery with chemotherapy are the only way to increase the survival rate.

In conclusion, the five year survival rate of leiomyosarcoas of the gallbladder is less than 5%. However for young and healthy patients with leiomyosarcomas of the gallbladder, aggressive surgical treatment followed by adjuvant chemotherapy should increase the survival rate despite high mortality and morbidity. Because of limited experience with this disease,  there is no consensus about management. Further studies are needed to confirm the benefit of aggressive treatment for patients with leiomyosarcoma of the gallbladder. Also surgeons will have to tread very carefully in selection of candidates for surgical treatments.

Primary Leiomyosarcoma of Gallbladder, thesurgery.or.kr 407