Extraskeletal osteosarcoma of the hand: the role of marginal excision and adjuvant radiation therapy

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HAND (2015) 10:602 606 DOI 10.1007/s11552-015-9760-0 REVIEW Extraskeletal osteosarcoma of the hand: the role of marginal excision and adjuvant radiation therapy Dana L. Casey 1 & Matt van de Rijn 2 & Geoffrey Riley 3 & Ka-Wah Tung 3 & David G. Mohler 4 & Sarah S. Donaldson 1,5 Published online: 17 April 2015 # American Association for Hand Surgery 2015 Abstract Background Extraskeletal osteosarcoma of the hand is rare, and its optimal modality of local control is not currently known. Methods A literature search was performed to identify studies that describe the treatment and outcomes of extraskeletal osteosarcoma. A second literature search was performed to identify studies that describe the treatment and outcomes of extraskeletal osteosarcoma of the hand specifically. Results The role of adjuvant radiation for extraskeletal osteosarcoma is not well defined. All cases in the literature describing treatment of extraskeletal osteosarcoma of the hand utilized amputation, and none of the patients described received radiation therapy. However, there are multiple reports showing excellent local control, minimal toxicity, and superior functional outcome with limb conservation and radiation rather than amputation of the hand in pediatric and adult soft tissue sarcoma. Conclusion For extraskeletal osteosarcoma of the hand, we recommend a treatment approach with the goal of preservation of form and function using limb-sparing surgery and planned postoperative radiation. * Sarah S. Donaldson sarah2@stanford.edu 1 2 3 4 5 Department of Radiation Oncology, Stanford University, Stanford, CA, USA Department of Pathology, Stanford University, Stanford, CA, USA Department of Radiology, Stanford University, Stanford, CA, USA Department of Surgery, Stanford University, Stanford, CA, USA Department of Radiation Oncology, Stanford University Cancer Center, 875 Blake Wilbur Drive, Stanford, CA 94305, USA Keywords Limb salvage. Radiation therapy. Soft tissue sarcoma. Osteosarcoma. Hand Background Extraskeletal osteosarcoma (ESOS) is a soft tissue sarcoma (STS) characterized by the production of malignant osteoid or bone. By definition, ESOS does not involve or attach to the skeleton. ESOS is rare, accounting for 2 5 % of osteosarcomas and <1 % of STS [12, 18].ESOSofthehandisevenmoreunusual,withthree reported cases in the literature [2, 4, 20]. Adjuvant treatment with radiation therapy (RT) for ESOS is not well defined. The hand specifically is a uniquely challenging site to irradiate given its functional importance. Surgery with chemotherapy is the accepted standard for treatment of osteosarcoma of osseous origin, including osteosarcoma of the bones of the hand [6, 13]. RT is used rarely as primary treatment for osteosarcoma of bone and more commonly reserved for palliation or distant metastases. While extremity STS is commonly approached with limb-sparing surgery and adjuvant RT [10, 16], limb conservation with adjuvant RT for ESOS of the hand has not previously been published. We review the current literature describing the characteristics, treatment, and outcomes of ESOS. We then review the literature describing ESOS of the hand specifically and discuss preservation of form and function using marginal excision and RT. Methods To review the characteristics, treatment, and outcomes of ESOS, we performed a MEDLINE literature search

HAND (2015) 10:602 606 603 identifying studies that met the following inclusion criteria: (1) reported on 15 or more cases of ESOS (all sites of disease included); (2) described the treatment modalities employed; (3) reported on local control and/or survival. We found a total of 10 retrospective reports meeting criteria. Only studies published in English and involving human subjects were considered. No reports were excluded based on study quality given the paucity of reports. To review the treatment and outcomes of ESOS of the hand specifically, a second MEDLINE literature search was performed with the following inclusion criteria: (1) reported on ESOS arising specifically from the hand; (2) identified the treatment modality used; (3) reported on outcome. Three case reports describing ESOS of the hand were identified. Results ESOS Characteristics There are less than 400 cases of ESOS reported in the literature [1, 3]. The median age at diagnosis is during the sixth to seventh decade, rather than the second decade as with primary osteosarcoma of the bone. The most common location at presentation is the lower extremity, specifically the thigh, and the most common site of distant spread is the lungs [3, 5, 17]. Histologic sections demonstrate a spindle cell proliferation with a chondromyxoid background and osteoid formation (Fig. 1). ESOS is almost always a high-grade sarcoma, with less than 10 cases of low-grade ESOS described [1, 17, 21]. ESOS Treatment and Outcomes Table 1 summarizes the 10 retrospective literature series describing ESOS. Surgery is the primary modality of treatment, with RT and chemotherapy given inconsistently and without standardized indications. The 3 5-year overall survival reported among the different reports varies widely, ranging from 25 to 77 %, while local tumor control has Fig. 1 Histologic sections show a malignant neoplasm with high-grade nuclear pleomorphism and osteoid formation (300 ) Table 1 Retrospective series describing extraskeletal osteosarcoma Study Number of patients Median age (years) Surgery (%) Radiation (%) Chemotherapy (%) Local control (%) Overall survival (%) Sordillo (1983) [18] 48 51 82 13 0 31 a 34 a Chung (1987) [5] 88 59 89 11 15 57 a 38.5 a Lee (1995) [9] 40 51 (mean) 100 28 5 55 a 37 c Lidang Jensen (1998) [11] 25 67 100 28 14 64 a <25 c McCarter (2000) [12] 15 61 100 33 40 93 a 50 c Ahmad (2002) [1] 60 55 92 16 63 82 c n/a Goldstein-Jackson (2005) [7] 17 44 94 6 94 71 a 77 b Torigoe (2007) [21] 20 50 (mean) 95 40 75 75 c 66 c Sio (2014) [17] 37 55 85 48 42 80 c 52 c Choi (2014) [3] 53 64 100 43 31 81 a 61 b a Crude rate b 3-year rate c 5-year rate

604 HAND (2015) 10:602 606 been similarly variable, with median values of 73 % [1, 3, 5, 7, 9, 11, 12, 17, 18, 21]. A retrospective series from MD Anderson Cancer Center demonstrated doxorubicin-based chemotherapy was not effective in ESOS, with only 19 % of patients experiencing radiograph partial or complete response and 6 % achieving pathologic complete response [1]. An earlier report suggested that ESOS was relatively resistant to platinum-based therapies [14]. Conversely, other studies suggest that multi-agent chemotherapyasusedinosteosarcomaofosseousoriginmaybeeffective in ESOS [7]. Thus, the role of chemotherapy in the treatment of ESOS is not well defined and requires further study. A study from Memorial Sloan Kettering Cancer Center evaluated the influence of RT among 42 patients with localized ESOS. The authors found no difference in event-free survival between those who received RT and/or chemotherapy and those who did not [3]. However, the patient numbers in each treatment subgroup were small, and the results thought to be influenced by selection bias; the patients who received postoperative RT and/ or chemotherapy had more unfavorable characteristics such as tumor size >5 cm or positive margins. This report did not evaluate the influence of RT on local control, the primary endpoint when evaluating efficacy of RT. Thus, the role of adjuvant RT, like the role of adjuvant chemotherapy, is not well defined. ESOS of the Hand ThreepreviouscasereportsofESOSofthehandhavebeen described (Table 2) [2, 4, 20]. All three patients were treated with either a partial amputation or below-elbow amputation (2 as the initial procedure, and 1 after local recurrence), and none received RT. One patient received chemotherapy. At our institution, we successfully treated a 29-year-old man with ESOS arising from a lumbrical muscle (Fig. 2) with function-preserving marginal excision and adjuvant RT. The patient has no functional deficits and retains full range of motion and sensation of his hand following his excision and adjuvant RT. Discussion Due to the variability in clinical and anatomic presentation of ESOS and its extreme rarity, it is difficult to obtain a sufficient sample size to evaluate its clinicopathologic characteristics and response to neoadjuvant or adjuvant therapy. It is necessary to extrapolate from either osteosarcoma of osseous origin or general adult STS data when assessing the role of marginal excision and RT for ESOS given the scarcity of reports in the published literature. The American Joint Committee on Cancer classifies ESOS as a STS. Many of the studies in Table 1 also report that ESOS is more similar in its behavior and response to chemotherapy to other STS than its histologic Table 2 Case reports of extraskeletal osteosarcoma of the hand Age (years) Size (cm) Grade Initial surgery Chemotherapy RT Recurrence Time to recurrence Treatment of recurrence Status Dead from metastatic disease to lung #1 [20] 56 3.9 2.9 2.5 3 Marginal excision No No Yes, local 4 months Below-elbow amputation + chemotherapy #2 [4] 63 5.5 5 5 3 Below-elbow amputation No No Yes, distant in lungs 18 months None Unknown #3 [2] 18 3 2.5 2 3 Partial amputation of Yes a No None 23 months, NED fourth + fifth distal rays RT radiation therapy, NED no evidence of disease a Neoadjuvant doxorubicin and ifosfamide and adjuvant methotrexate, doxorubicin, and cisplatin

HAND (2015) 10:602 606 605 Fig. 2 a Axial and b coronal proton density MRI with fat saturation demonstrate a hyperintense 2.2 1.6 2.9-cm solid mass in the palm between the flexor tendons of the third and ring finger, replacing or arising from the lumbrical muscle counterpart in the bone [1, 3, 12]. Thus, extrapolation from STS literature appears most appropriate. Optimal treatment of extremity STS usually involves the combination of limb-sparing surgery and RT. Over 30 years ago, a National Cancer Institute (NCI) prospective trial showed that amputation provided no survival advantage over limb-sparing surgery and RT for extremity STS [15]. A second prospective trial from the NCI then explored if radiation could be omitted after limb-sparing surgery. Patients with high-grade extremity STS who underwent limb-sparing surgery were randomized to receive adjuvant chemotherapy versus adjuvant chemoradiation and patients with low-grade tumors to adjuvant RT versus observation [22]. RT improved local control in patients with both high- and low-grade disease. Local control was 100 % in patients with high-grade STS treated with gross total resection and adjuvant RT [22]. For sarcomas of the hand or foot specifically, complete surgical resection with wide margins is challenging without amputation due to anatomic constraints and lack of expendable tissue. All three case reports in the literature describing ESOS of the hand utilized amputation, and none of the patients described received radiation therapy [2, 4, 20]. However, there are multiple reports showing excellent local control, minimal toxicity, and superior functional outcome with limb conservation and RT rather than amputation of the hand in pediatric and adult STS [8, 10, 16, 19]. In particular, RT improves local control in patients with hand STS who do not undergo re-excision to achieve wide margins [10]. The morbidity of irradiating the distal extremity using modern conformal techniques today is low, with very few patients developing limb dysfunction [16, 19]. Posttreatment physical therapy and careful treatment techniques such as avoidance of circumferential radiation while limiting the dose to the skin and joint can minimize treatment-related effects. The decision to add RT in the setting of a margin-negative resection is based on risks and benefits. Even with negative margins, high-grade tumors can recur locally. Additionally, in this anatomic area, local recurrence would almost certainly result in partial or complete amputation of the hand. Therefore, we consider the small risk of secondary cancers, fractures, and other potential radiation morbidities to be acceptable given the severity of the consequences of local recurrence. In summary, ESOS of the hand is a rare diagnosis, and its optimal modality of local control is unknown. Based on the current literature, we recommend a treatment approach with the goal of preservation of form and function using limbsparing surgery and planned postoperative radiation. Conflict of Interest Dana L. Casey declares that she has no conflict of interest, commercial association, or intent of financial gains regarding this article. Matt van de Rijn declares that he has no conflict of interest, commercial association, or intent of financial gains regarding this article. Geoffrey Riley declares that he has no conflict of interest, commercial association, or intent of financial gains regarding this article. Ka-Wah Tung declares that he has no conflict of interest, commercial association, or intent of financial gains regarding this article. David G. Mohler declares that he has no conflict of interest, commercial association, or intent of financial gains regarding this article. Sarah S. Donaldson declares that she has no conflict of interest, commercial association, or intent of financial gains regarding this article. Statement of Human and Animal Rights This article does not contain any studies with human or animal subjects. Statement of Informed Consent was included in this article. Funding References None No patient-identifying information 1. Ahmad SA, Patel SR, Ballo MT, et al. Extraosseous osteosarcoma: response to treatment and long-term outcome. J Clin Oncol. 2002;20:521 7.

606 HAND (2015) 10:602 606 2. Bellan DG, Reynaldo JG, Sexia-Alves MT, et al. Extraskeletal osteosarcoma of the hand in an adolescent: a case report. JBJS Case Connect. 2013;3:e6. 3. Choi LE, Healey JH, Kuk D, et al. Analysis of outcomes in extraskeletal osteosarcoma: a review of fifty-three cases. J Bone Joint Surg Am. 2014;96, e2. 4. Cook PA, Murphy MS, Innis PC, et al. Extraskeletal osteosarcoma of the hand. A case report. J Bone Joint Surg Am. 1998;80:725 9. 5. Chung EB, Enzinger FM. Extraskeletal osteosarcoma. Cancer. 1987;60:1132 42. 6. Daecke W, Bielack S, Martini AK, et al. Osteosarcoma of the hand and forearm: experience of the cooperative osteosarcoma study group. Ann Surg Oncol. 2005;12:322 31. 7. Goldstein-Jackson SY, Gosheger G, Delling G, et al. Extraskeletal osteosarcoma has a favourable prognosis when treated like conventional osteosarcoma. J Cancer Res Clin Oncol. 2005;131:520 6. 8. La TH, Wolden SL, Su Z, et al. Local therapy for rhabdomyosarcoma of the hands and feet: is amputation necessary? A report from the children's oncology group. Int J Radiat Oncol Biol Phys. 2011;80:206 12. 9. Lee JS, Fetsch JF, Wasdhal DA, et al. A review of 40 patients with extraskeletal osteosarcoma. Cancer. 1995;76:2253 9. 10. Lin PP, Guzel VB, Pisters PW, et al. Surgical management of soft tissue sarcomas of the hand and foot. Cancer. 2002;95:852 61. 11. Lidang Jensen M, Schumacher B, Myhre Jensen O, et al. Extraskeletal osteosarcomas: a clinicopathologic study of 25 cases. Am J Surg Pathol. 1998;22:588 94. 12. McCarter MD, Lewis JJ, Antonescu CR, et al. Extraskeletal osteosarcoma: analysis of outcome of a rare neoplasm. Sarcoma. 2000;4: 119 23. 13. Okada K, Wold LE, Beabout JW, et al. Osteosarcoma of the hand. A clinicopathologic study of 12 cases. Cancer. 1993;72:719 25. 14. Patel SR, Benjamin RS. Primary extraskeletal osteosarcoma experience with chemotherapy. J Natl Cancer Inst. 1995;87:1331 3. 15. Rosenberg SA, Tepper J, Glatstein E, et al. The treatment of softtissue sarcomas of the extremities: prospective randomized evaluations of (1) limb-sparing surgery plus radiation therapy compared with amputation and (2) the role of adjuvant chemotherapy. Ann Surg. 1982;196:305 15. 16. Schoenfeld GS, Morris CG, Scarborough MT, et al. Adjuvant radiotherapy in the management of soft tissue sarcoma involving the distal extremities. Am J Clin Oncol. 2006;29:62 5. 17. Sio TT, Vu CC, Sohawon S, et al. Extraskeletal osteosarcoma: an international rare cancer network study. Am J Clin Oncol. 2014. 18. Sordillo PP, Hajdu SI, Magill GB, et al. Extraosseous osteogenic sarcoma. A review of 48 patients. Cancer. 1983;51:727 34. 19. Talbert ML, Zagars GK, Sherman NE, et al. Conservative surgery and radiation therapy for soft tissue sarcoma of the wrist, hand, ankle, and foot. Cancer. 1990;66:2482 91. 20. Tan KT, Idowu OK, Chandrasekar CR, et al. Extraskeletal osteosarcoma of the hand. Hand. 2012;7:124 6. 21. Torigoe T, Yazawa Y, Takagi T, et al. Extraskeletal osteosarcoma in Japan: multiinstitutional study of 20 patients from the Japanese musculoskeletal oncology group. J Orthop Sci. 2007;12:424 9. 22. Yang JC, Chang AE, Baker AR, et al. Randomized prospective study of the benefit of adjuvant radiation therapy in the treatment of soft tissue sarcomas of the extremity. J Clin Oncol. 1998;16:197 203.