Leiomyosarcoma of the skin: review of the literature with an emphasis on prognosis and management

Clinical Variables Influencing Outcomes in Patients with Atypical Intradermal Smooth Muscle Neoplasms (Formerly Cutaneous Leiomyosarcomas): Single-Institution Study of 95 Surgical Patients

BACKGROUND

Atypical intradermal smooth muscle neoplasm, also commonly termed cutaneous leiomyosarcoma, is a soft tissue tumor with a low risk of aggressive behavior. These lesions arise in the dermis with possible superficial subcutaneous extension, demonstrate cytologic atypia, and often show mitotic activity.

METHODS

A retrospective review of patient demographics, tumor characteristics, and treatment methods was conducted in a consecutive series of patients presenting to MD Anderson Cancer Center (MDACC) from 2002 to 2021 (n = 95). All pathology was reviewed by MDACC pathologists and determined to be atypical intradermal smooth muscle neoplasm.

RESULTS

Median age at diagnosis was 58 years (range 22-86), and 74% were male. Ninety-five percent (n = 90) of patients identified as White, non-Hispanic. Most tumors were slow-growing, solitary, and painless nodules. Tumors were in the lower extremities (44.2%), followed by the upper extremity (28.4%), trunk (22.1%), and head and neck (5.2%). All patients (n = 44, 46.3%) who had a punch/incisional biopsy for diagnostic purposes had a subsequent tumor excision. Unplanned excision or excisional biopsy was performed on the remaining 46 (48%) patients. Of this subset, 41 of the 46 aforementioned patients (89%) had positive margins and underwent re-excision. Final pathology in 25/38 (66%) re-excision specimens was negative for residual tumor despite an initial positive margin. Two patients in the cohort had local recurrence 2 and 3 years after initial surgery. Both patients had positive margins, underwent excision of the recurrent tumor, and remain free of disease. After median follow-up of 6.9 years (range 1 day-18 years), 5-year recurrence-free survival was 96% and overall survival (OS) of the entire cohort was 78%.

CONCLUSION

In this study of consecutive patients presenting with atypical intradermal smooth muscle neoplasm, we found good OS and local control after definitive surgical excision with negative margins, including excisional biopsy with close margins. Atypical intradermal smooth muscle neoplasm is unlikely to metastasize and has an excellent prognosis. Guidelines to determine optimal surveillance strategies for these patients should be revisited.

Retrospective Single-Center Case Study of Clinical Variables and the Degree of Actinic Elastosis Associated with Rare Skin Cancers

(1) Background: Rare skin cancers include epithelial, neuroendocrine, and hematopoietic neoplasias as well as cutaneous sarcomas. Ultraviolet (UV) radiation and sunburns are important drivers for the incidence of certain cutaneous sarcomas; however, the pathogenetic role of UV light is less clear in rare skin cancers compared to keratinocyte cancer and melanoma. In this study, we compared the degree of actinic elastosis (AE) as a surrogate for lifetime UV exposure among selected rare skin cancers (atypical fibroxanthoma [AFX], pleomorphic dermal sarcoma [PDS], dermatofibrosarcoma protuberans [DFSP], Kaposi sarcoma [KS], Merkel cell carcinoma [MCC], and leiomyosarcoma [LMS]) while taking into account relevant clinical variables (age, sex, and body site). (2) Methods: We newly established a semi-quantitative score for the degree of AE ranging from 0 = none to 3 = total loss of elastic fibers (basophilic degeneration) and multiplied it by the perilesional vertical extent (depth), measured histometrically (tumor-associated elastosis grade (TEG)). We matched the TEG of n = 210 rare skin cancers from 210 patients with their clinical variables. (3) Results: TEG values were correlated with age and whether tumors arose on UV-exposed body sites. TEG values were significantly higher in AFX and PDS cases compared to all other analyzed rare skin cancer types. As expected, TEG values were low in DFSP and KS, while MCC cases exhibited intermediate TEG values. (4) Conclusions: High cumulative UV exposure is more strongly associated with AFX/PDS and MCC than with other rare skin cancers. These important results expand the available data associated with rare skin cancers while also offering insight into the value of differentiating among these tumor types based on their relationship with sun exposure, potentially informing preventative, diagnostic and/or therapeutic approaches.

Cutaneous leiomyosarcoma: a retrospective review of 45 cases

Primary cutaneous leiomyosarcoma (LMS) is a rare soft tissue tumour type with two subtypes, dermal and subcutaneous. As deeper tumours confer a worse prognosis, they require a more aggressive approach. Conversely, a more conservative surgical approach for dermal LMS has been suggested. Few studies have comprehensively reported both clinical surgical and histological excision margins. Therefore, we sought to provide margin recommendations based on our experience and review of the existing literature. We undertook a retrospective case-note review (1998-2019) of cutaneous LMS management to establish histological/surgical margins using pathology/electronic patient records. The diagnosis was made and classified by an experienced dermatopathologist according to the World Health Organization classification. In the dermal LMS cohort (n = 35), mean peripheral and deep histological margins were 5.4 mm (range 0.5-20) and 5.6 mm (range 0.1-14.5), respectively. The incomplete excision rate was 31% (11 of 35). There were no recurrences. In the subcutaneous LMS cohort (n = 10), mean peripheral and deep histological margins were 5.7 mm (range 0.2-14) and 1.1 mm (range 0.2-1.7), respectively. The incomplete excision rate was 40% (4 of 10). The recurrence rate was 20% (2 of 10) despite achieving histological clearance after 1 year. One lung metastasis occurred 1 year following an adequately excised primary scalp LMS. Thus, for dermal LMS we propose a clinical margin of 5-10 mm (depending on lesion size) at the initial excision or at scar re-excision following involved/close histological peripheral and/or deep margins (i.e. < 1 mm). For subcutaneous LMS, we suggest a clinical margin of 15-20 mm (depending on lesion size) to achieve a peripheral histological clearance of 10 mm and negative deep margin (i.e. > 1 mm), down to the periosteum/fascia/muscle according to anatomical site. If this is not achieved, a re-excision would be recommended. However, prospective studies are needed for optimal guidance.

Frontal cutaneous leiomyosarcoma: A case report and review of the literature

Sarcomas are a heterogeneous group of mesenchymal tumours that can affect the skin. They are dominated by Kaposi's sarcoma and dermatofibrosarcoma. Cutaneous leiomyosarcoma is a very rare entity. We report the case of a 78-year-old patient who presented with a primary frontal cutaneous leiomyosarcoma treated surgically with a good outcome at the last follow-up. The objective of this work is to identify the epidemiological, clinical, anatomopathological, therapeutic and prognostic particularities of this pathology through a review of the literature.

Clinical update on cutaneous and subcutaneous sarcomas

BACKGROUND

Cutaneous sarcomas are uncommon cancers that can have a wide range of clinical symptoms and lead to considerable cutaneous as well as systemic morbidity.

AIM

The objective of this review article is to discuss epidemiology, clinical features, diagnosis, and therapy of different types of cutaneous sarcomas.

MATERIAL AND METHODS

Literature was screened to retrieve articles from PubMed/Medline and Google Scholar and related websites. Cross-references from the relevant articles were also considered for review. Review articles, clinical studies, systematic reviews, meta-analyses, and relevant information from selected websites were included.

RESULTS AND DISCUSSION

Cutaneous sarcomas have a negative effect on the quality of life. In their diagnosis, clinical presentation and histological evaluation are crucial. Complete surgical removal is the solution for more or less all cutaneous and subcutaneous sarcomas. The prognosis for cutaneous sarcomas is generally favorable since they tend to recur locally with distant metastases only on rare occasions. Patients having advanced disease should be treated in the setting of clinical trials if possible; choices include radiation therapy and systemic medicines. The value of innovative immunotherapy cannot be determined decisively at this time due to a paucity of relevant trials.

CONCLUSION

As cutaneous sarcomas are rarely diagnosed based on clinical findings, histology plays an important role in the diagnosis. They have a relatively favorable prognosis if treated properly. Patients should be treated at specialized centres.

Case report and literature review: Primary leiomyosarcoma of the penis

Background

Leiomyosarcoma (LMS) is a malignant spindle-cell mesenchymal tumor originating from the smooth muscle cells, which mostly affects soft tissues and abdominopelvic organs over extremities. Primary LMS of the penis is a relatively uncommon mesenchymal tissue disease and a poorly understood condition.

Case Report

A 69-year-old man presented with a growing, painless mass protruding from the penis. The irregularly lobulated lump was roughly 3 cm × 2.5 cm, with a smooth surface, tough texture, distinct boundary, and no tenderness. It was determined to be a penile tumor during the preoperative radiological evaluation. The patient underwent resection of the penile mass, followed by extended resection in the second operation. The diagnosis of LMS was verified by pathological examination. During a 20-month follow-up, the patient made a smooth recovery and remained disease-free.

Conclusion

An immunohistochemical examination is essential for rendering this rare diagnosis. Radical excision of tumor lesions with negative cut margins is guaranteed to be the best treatment for primary penile LMS. Close follow-up should be provided due to the high rate of local recurrence.

Grade of Primary Cutaneous Leiomyosarcoma Dictates Risk for Metastatic Spread and Disease-Specific Mortality

BACKGROUND AND OBJECTIVES

Primary cutaneous leiomyosarcoma (cLMS), a rare, typically intradermal tumor, has previously been reported to exhibit an indolent course of disease with zero-to-low risk of local recurrence or distant metastasis. This study seeks to evaluate recurrence and survival of cLMS patients through study of its clinicopathologic and treatment characteristics.

METHODS

All patients included underwent resection of primary cLMS at this institution between 2006 and 2019. A retrospective cohort study analysis of clinicopathologic characteristics, treatment, recurrence, and overall survival was performed. Data was assessed through descriptive statistics and outcome measures assessed by Cox proportional models and log-rank tests.

RESULTS

Eighty-eight patients with cLMS were evaluated. The majority were men (n = 68, 77%) and Caucasian (n = 85, 97%), with median age at diagnosis of 66 years (range 20-96). 65% of tumors were located on the extremities, with a median size of 1.3 cm (range .3-15). Assessment revealed low (n = 41, 47%), intermediate (n = 29, 33%), and high (n = 18, 20%) grade tumors, demonstrating extension into subcutaneous tissue in 38/60 (60%), with 3 patients exhibiting extension into muscle (3%). All underwent resection as primary treatment with median 1 cm margins (range .5-2). With median follow-up of 27.5 months (IQR 8-51; range 1-131), no low-grade cases had recurrence or death while there was a recurrence rate of 19.1% (9/47) and death rate of 8.5% (4/47) in intermediate- to high-grade cases.

CONCLUSIONS

Primary tumor resection of cLMS provides excellent local control for low-grade tumors as no low-grade cases experienced recurrence. For patients with intermediate- to high-grade tumors, there is potential for local recurrence, distant metastasis, and death, and therefore surveillance following treatment is encouraged.

Increase of atypical fibroxanthoma and pleomorphic dermal sarcoma: a retrospective analysis of four German skin cancer centers

BACKGROUND AND OBJECTIVES

In recent years, considerable insight has been gained into the pathogenesis, diagnosis and treatment of cutaneous sarcomas, including atypical fibroxanthoma (AFX) and pleomorphic dermal sarcoma (PDS). Both entities have shown increasing incidence rates in the last decade. This study was initiated to evaluate how these new insights impact the number of diagnoses of AFX/PDS compared to other cutaneous sarcoma entities.

PATIENTS AND METHODS

In a retrospective study of four German skin cancer centers, all histopathological reports of cutaneous sarcomas (AFX, PDS, dermatofibrosarcoma protuberans, cutaneous leiomyosarcoma, angiosarcoma, and Kaposi sarcoma) confirmed by board-certified dermatopathologists were analyzed during a time-period of seven years (2013-2019). Additionally, utilization of immunohistochemical markers (including pan-cytokeratin, S100, desmin, CD34, CD10, procollagen-1, CD99, CD14, and CD68) as an adjunct to diagnose AFX/PDS was recorded.

RESULTS

Overall, 255 cutaneous sarcomas were included in the present study. The diagnosis of a cutaneous sarcoma has consequently risen from 2013 to 2019 (from 16 to 52 annual cases). The results of AFX/PDS revealed 4.6 times more diagnoses in 2019 than in 2013. Atypical fibroxanthoma represented the most common subtype, displaying 49.3 % of all diagnosed cutaneous sarcomas. Additionally, the increase of AFX/PDS was linked to the use of immunohistochemistry, with specific immunohistochemical markers used in 57.1 % of cases in 2013 compared to 100 % in 2019.

CONCLUSIONS

This retrospective study of four German skin cancer centers demonstrates a substantial rise of AFX/PDS, possibly due to recently established diagnostic and terminology standards. This rise is probably linked to increased utilization of specific immunohistochemical markers. Atypical fibroxanthoma/PDS may be more common than previously thought and seems to represent the most frequent cutaneous sarcoma subtype.

Zunahme des atypischen Fibroxanthoms und pleomorphen dermalen Sarkoms: eine retrospektive Analyse vier deutscher Hauttumorzentren

HINTERGRUND UND ZIELE

In den letzten Jahren konnten umfassende Erkenntnisse über die Pathogenese, Diagnostik und Behandlung von kutanen Sarkomen, insbesondere des atypischen Fibroxanthoms (AFX) und pleomorphen dermalen Sarkoms (PDS) gesammelt werden. Beide Entitäten zeigten innerhalb der letzten Dekade steigende Inzidenzraten. Die vorliegende Studie diente der Untersuchung, welchen Einfluss die neuen Erkenntnisse auf die Fallzahlen von AFX/PDS im Vergleich zu anderen Sarkom-Entitäten haben.

PATIENTEN UND METHODIK

Diese retrospektive Studie wurde an vier deutschen Hauttumorzentren durchgeführt und alle von zertifizierten Dermatopathologen bestätigten histopathologischen Befunde von kutanen Sarkomen (AFX, PDS, Dermatofibrosarcoma protuberans, kutanes Leiomyosarkom, Angiosarkom und Kaposi-Sarkom) in einem Zeitraum von sieben Jahren (2013-2019) evaluiert. Zusätzlich wurde der Einsatz von immunhistochemischen Markern als diagnostische Hilfe (Panzytokeratin, S100, Desmin, CD34, CD10, Prokollagen-1, CD99, CD14 und CD68) erfasst.

ERGEBNISSE

Insgesamt konnten 255 kutane Sarkome in die vorliegende Studie eingeschlossen werden. Die Zahl der kutanen Sarkome nahm kontinuierlich von 2013 bis 2019 zu (von 16 auf 52 Fälle im Jahr). Die Diagnose eines AFX/PDS konnte in 2019 4,6-mal häufiger als in 2013 gestellt werden. Das AFX stellte mit 49,3 % aller kutanen Sarkome den häufigsten Sarkom-Subtypen dar. Zusätzlich war der Anstieg von AFX/PDS mit dem Einsatz von Immunhistochemie assoziiert. Der Einsatz von spezifischen Immunhistochemischen Markern stieg von 57,1 % im Jahr 2013 auf 100 % in 2019.

SCHLUSSFOLGERUNGEN

Diese retrospektive Studie von vier deutschen Hauttumorzentren demonstriert eine substanzielle Zunahme von AFX/PDS, wahrscheinlich infolge kürzlich etablierter beziehungsweise verbesserter diagnostischer und terminologischer Standards. Dieser Anstieg ist vermutlich mit dem vermehrten Einsatz von bestimmten immunhistochemischen Markern assoziiert. AFX/PDS treten wahrscheinlich häufiger auf als bisher vermutet und repräsentieren möglicherweise den häufigsten kutanen Sarkom-Subtyp.

Development, validation, and visualization of a web-based nomogram for predicting the incidence of leiomyosarcoma patients with distant metastasis

BACKGROUND

Leiomyosarcoma (LMS) is one of the most common soft tissue sarcomas. LMS is prone to distant metastasis (DM), and patients with DM have a poor prognosis.

AIM

In this study, we investigated the risk factors of DM in LMS patients and the prognostic factors of LMS patients with DM.

METHODS AND RESULTS

LMS patients diagnosed between 2010 and 2016 were extracted from the Surveillance, Epidemiology, and End Result (SEER) database. Patients were randomly divided into the training set and validation set. Univariate and multivariate logistic regression analyses were performed, and a nomogram was established. The area under the curve (AUC), calibration curve, and decision curve analysis (DCA) were used to evaluate the nomogram. Based on the nomogram, a web-based nomogram is established. The univariate and multivariate Cox regression analyses were used to assess the prognostic risk factors of LMS patients with DM. Eventually, 2184 patients diagnosed with LMS were enrolled, randomly divided into the training set (n = 1532, 70.14%) and validation set (n = 652, 29.86%). Race, primary site, grade, T stage, and tumor size were correlated with DM incidence in LMS patients. The AUC of the nomogram is 0.715 in training and 0.713 in the validation set. The calibration curve and DCA results showed that the nomogram performed well in predicting the DM risk. A web-based nomogram was established to predict DM's risk in LMS patients (https://wenn23.shinyapps.io/riskoflmsdm/). Epithelioid LMS, in uterus, older age, giant tumor, multiple organ metastasis, without surgery, and chemotherapy had a poor prognosis.

CONCLUSIONS

The established web-based nomogram (https://wenn23.shinyapps.io/riskoflmsdm/) is an accurate and personalized tool to predict the risks of LMS developing DM. Advanced age, larger tumor, multiple organ metastasis, epithelioid type, uterine LMS, no surgery, and no chemotherapy were associated with poor prognosis in LMS patients with DM.

Scalp Reconstruction in Delayed Diagnosed Dermal Leiomyosarcoma Mimicking Keloid Scar

ABSTRACT

Leiomyosarcoma (LMS) of the skin is a rare smooth muscle neoplasm of all soft tissue sarcoma. Because of its prognostic importance, early diagnosis is critical for successful treatment. Since several features and clinical manifestations are similar to those of a keloid scar, the differential diagnosis between these two diseases is difficult, especially in the early stages of cancer that do not show any remarkable features in appearance, or when the patient has a history of previous wounds or surgery.In our case report, a 71-year-old female patient who underwent a scalp reconstruction using an anterolateral thigh flap turned out to have, because of delayed diagnosis, a dermal LMS mimicking a keloid scar. The case emphasizes careful physical examination for early intervention, even if a lesion looks like a typical keloid scar. After resection, the appropriate reconstruction method can be selected based on the complexity of the defect site.

Advanced Cutaneous Leiomyosarcoma of the Forearm

Leiomyosarcoma is a malignant smooth muscle neoplasm, which is traditionally divided into superficial and deep tumors. Superficial leiomyosarcomas are quite rare entities, accounting for approximately 7% of soft tissue neoplasms and 0.04% of all cancers. Here we describe a rare case of advanced primary cutaneous leiomyosarcoma (PCL) in a 93-year-old woman, highlighting the considerable size of the lesion and the correct surgical and oncological management. The clinical story began about 4 years ago, and the neoplasia was treated only with local radiotherapy, but the patient suffered from a dramatic volumetric increase of the right arm sarcoma one year ago. Then, an amputation of the limb was performed without following adjuvant chemotherapy. Currently, she does not show signs of recurrence and is in good shape.

Epithelioid Cutaneous Mesenchymal Neoplasms: A Practical Diagnostic Approach

Epithelioid cells are rounded or polygonal cells with abundant eosinophilic or clear cytoplasm and ovoid to round nuclei, superficially resembling epithelial cells. Cutaneous mesenchymal neoplasms composed predominantly or exclusively of epithelioid cells are relatively uncommon and can cause considerable diagnostic difficulties due to overlapping histologic features among heterogeneous groups of tumors. Familiarity with practical diagnostic approaches and recognition of key histopathologic features are important for correct diagnosis and management. This review summarizes the histologic features of epithelioid cutaneous mesenchymal neoplasms and discusses their differential diagnoses from malignant melanomas and carcinomas.

Clear-cell variant of superficial cutaneous leiomyosarcoma associated with RB1 mutation: Clinical, dermoscopic, and histopathological characteristics

Leiomyosarcoma is a relatively rare soft tissue tumor whose clear-cell variant has only been reported in leiomyosarcomas of the uterus. We report here for the first time a primary cutaneous clear-cell leiomyosarcoma in the trunk skin of a 49-year-old man, characterized by a very indolent clinical and dermoscopic presentation, mimicking a dermatofibroma. Genetic analysis of the otherwise healthy patient revealed a germline mutation in the retinoblastoma 1 gene (RB1); the same mutation was found in his son, who had previously developed retinoblastoma. Moreover, the mother of the patient had died of uterine leiomyosarcoma with clear-cell changes. Mutations in the RB1 gene occur commonly in human neoplasms. In this patient, we were able to link his clear-cell variant of cutaneous leiomyosarcoma with the loss of retinoblastoma protein expression, as revealed by immunohistochemical staining analysis.