Giant Cutaneous Leiomyosarcoma Originating From the Abdominal Wall: A Case Report

Background

Leiomyosarcoma, which is a rare type of tumor, accounts for 5–10% of all soft tissue tumors [1,2]. Cutaneous leiomyosarcoma is a less common subgroup and, although it can be seen in any age groups, the prevalence is highest between the 5th and 7th decades. It is more frequent in extensor surfaces that have higher hair content on the extremities [3]. It arises from the arrector pili muscle of hair follicles. In the initial diagnosis, cutaneous leiomyosarcoma is a tumor usually smaller than 2 cm [4]. The behavior of these tumors is more consistent with that of deeper tumors than intradermal tumors. We report an interesting case of a leiomyosarcoma with an uncommon location and size.

Case Report

HISTOPATHOLOGICAL FINDINGS:

Macroscopic evaluation revealed a lesion with the dimensions of 45×35×15 and an elliptical skin surface of 45×35 cm, which had a nodular appearance. There was a hard, gray-white-colored, lobulated mass with relatively regular borders, and dimensions of 26×24×15 cm. Fibrillary deposits were visible in the cross-section of the material.

In histopathological evaluation, the tumor formation was characterized by a number of atypical cells extending in various directions as clusters that were fusiform and spindle-like, and had obtuse ends, with hyperchromatic nuclei and pale eosinophilic cytoplasms (Figure 6). There were widespread necrosis spots in the tumor, and 6 mitosis regions in a single area of ×10 magnification.

Although immunohistochemical studies revealed immunoreactivity with vimentin and smooth muscle actin, there was no immunoreactivity with CD 117 or S100 in tumor cells (Figure 7). The diagnosis of cutaneous leiomyosarcoma was made based on morphological and immunohistochemical findings.

At 3-year follow-up there was no recurrence or metastasis.

Discussion

There are various types of gastrointestinal cancers [5–7]. Soft tissue sarcomas are rare neoplasms that constitute approximately 1% of all adulthood cancers [5]. The locations of these tumors are: 43% in the extremities, 19% in the organs, 15% in the retroperitoneal space, 10% in the body/chest, and 13% in other areas [8]. Leiomyosarcomas constitute 5–10% of these tumors [1,2]. When 6486 patients diagnosed with soft tissue sarcomas in Memorial Sloan-Kettering Cancer Center between July 1st 1982 and June 30th 2005 were reviewed, it was observed that 15% of them (978 cases) were leiomyosarcomas [8].

Leiomyosarcomas are classified into 4 main groups. The first group includes leiomyosarcoma of the retroperitoneal space and abdominal cavity and is the most common subgroup. The second group is soft tissue leiomyosarcoma, which has a better prognosis. The third group is cutaneous leiomyosarcomas; because its localization is superficial, the prognosis is better than in the other groups. The fourth subgroup includes vascular leiomyosarcomas [9]; these tumors, which occur more frequently in adulthood, are more prevalent in females than males, whereas cutaneous leiomyosarcomas are more common in males than in females [3].

It was previously suggested that cutaneous leiomyosarcomas originate from the dermis or subcutaneous tissue, but it was recently precluded that these lesions develop from the dermis, later extending this to subcutaneous tissues [9]. Even its etiology is not clearly defined; precancerous lesions, physical trauma, and radiation exposure are reported as possible causative factors [3]. Cutaneous tumors are generally smaller than 2 cm at the time of early diagnosis [3,9]. Generally, they include cutaneous findings like color changes, umbilications, and ulcerations. As the tumor develops, it extends to subcutaneous tissues, compresses surrounding tissues, and may form a pseudocapsule [9].

Leiomyosarcomas have only limited response to radiotherapy or chemotherapy [3]. Immunotherapy and gene therapy are treatment models still at developmental stages. The only treatment option with proven success is surgery [10,11].

In cutaneous leiomyosarcomas, a 42% local recurrence rate was reported by Fields and Helwig [3] and 14% by Bernstein and Roenigk [12] and Jensen et al. [4].

Conclusions

Leiomyosarcoma of the skin is a rare condition and our case is the largest such lesion in the literature. The patient’s psychosis, associated with a superstitious belief, allowed the mass to reach an enormous size. After extensive resection, the prognosis of the patient was good at 3-year follow-up.