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Year : 2018  |  Volume : 11  |  Issue : 3  |  Page : 248-251  

Giant intra-articular synovial chondromatosis of knee joint mimicking malignancy: A rare case report

Department of Pathology, Yashoda Hospital, Hyderabad, Telangana, India

Date of Web Publication29-Jun-2018

Correspondence Address:
Abhijeet Ingle
Yashoda Hospital, Malakpet, Nalgonda X Roads, Hyderabad - 500 036, Telangana
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Source of Support: None, Conflict of Interest: None


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Synovial chondromatosis is a rare benign condition arising from the synovial membrane of the joints, synovial sheaths, or bursae around the joints. Primary synovial chondromatosis typically affects the large joints in the third to fifth decade of life. The purpose of this case report is to document this rare giant synovial pathology, which was mimicking malignancy clinically but diagnosed as intra-articular synovial chondromatosis histopathologically. In our case, the gross size was measuring 11 cm × 8 cm × 6 cm.

Keywords: Giant, knee joint, synovial chondromatosis

How to cite this article:
Ingle A, Rachakonda S, Kumar N A, Satyanarayana S. Giant intra-articular synovial chondromatosis of knee joint mimicking malignancy: A rare case report. Med J DY Patil Vidyapeeth 2018;11:248-51

How to cite this URL:
Ingle A, Rachakonda S, Kumar N A, Satyanarayana S. Giant intra-articular synovial chondromatosis of knee joint mimicking malignancy: A rare case report. Med J DY Patil Vidyapeeth [serial online] 2018 [cited 2021 Jun 12];11:248-51. Available from: https://www.mjdrdypv.org/text.asp?2018/11/3/248/235569

  Introduction Top

Synovial osteochondromatosis (SOC) is a monoarticular, synovial disease. It is a rare disease which presents as multiple cartilaginous nodule formations in synovial joints, bursae, or tendon sheaths.[1],[2],[3] Mostly although it is generally a primary condition, it can be secondary to other conditions such as osteoarthritis. This disease is more prevalent in the fourth and fifth decades. It affects males more than females,[1],[2] but in our case, it is female of the sixth decade associated with Grade 4 osteoarthritis. SOC most commonly involves knee joint with a frequency of 55%–65%. Other places that are involved frequently include other joints such as hip, elbow, shoulder, and ankle. It rarely involves temporomandibular joint.[4] Synovial chondromatosis of the temporomandibular joint is four times more common in women than in men.[5] The symptoms are pain and swelling, sometimes joint effusions, locking, and tenderness may also occur.[6] Synovial chondromatosis is also called as chondrometaplasia [2] or Reichel's syndrome.[7]

  Case Report Top

A female aged 60 years came to Orthopedic Department at Yashoda Hospital, Malakpet, with pain in both knee joints with a history of diabetes and hypertension. The patient had difficulty in standing and walking with relief of pain on rest and nonsteroidal anti-inflammatory drugs. On examination, there were bilateral varus deformity, large swelling over the right knee, and restricted movements. The patient was admitted for bilateral total knee replacement. Complete blood picture revealed leukocytosis with eosinophilia and high erythrocyte sedimentation rate. X-ray revealed right genu varus and left genu valgus deformity, large osteophytes on tibial, femoral condyles and patella, well-circumscribed lobulated calcific density in suprapatellar recess likely myositis ossificans, or large osteophyte complex [Figure 1].
Figure 1: X-ray images showing radiodense opacity in lower end of femur in lateral view

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Intraoperative findings revealed a mass measuring 11 cm × 8 cm × 6 cm and weighing 250 g retrieved from intra-articular space attached to synovium. On gross examination, there was a pearly white hard mass measuring 11 cm × 8 cm × 6 cm and attached soft tissue mass measuring 4 cm × 3 cm × 1 cm. On cut section, the mass was multinodular and showed pearly white areas; cystic areas were also seen [Figure 2]. Microscopy showed a tumor composed of cartilaginous matrix with chondrocytes, focally the chondrocytes show increased cellularity and 1–2 chondrocytes per lacunae. The chondromyxoid matrix is seen in between the metaplastic bony trabeculae. The interstitium also showed fat [Figure 3] and [Figure 4].
Figure 2: Gross image showing tumor mass with cartilaginous element and adipose tissue

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Figure 3: H and E section showing cartilage and beneath it layer of adipose tissue, ×10 view

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Figure 4: H and E section showing cartilaginous areas, high power view, ×40 view

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  Discussion Top

Synovial chondromatosis is a rare, mono-articular benign neoplasm with an unknown cause. It occurs at any joint and tendon sheath that have synovial tissue. It is characterized by cartilaginous nodule formation secondary to synovial metaplasia. The nodules may show calcification. It is progressive in nature, it can be self limited and can also regress.[3] Delay in diagnosis of synovial chondromatosis can occur due to slow progression of disease with calcification of free cartilage fragments at late stage.[8] Patient's complaints are usually due to mechanical effects of free bodies. It is aggravated by infection and trauma.[9],[10] Milgram [11] defined this disease in three stages: Stage I which is the early stage or the active intrasynovial stage and Stage II which is the transition stage from intrasynovial disease to free bodies. In Stage III (late stage), there are multiple free bodies but the absence of intrasynovial involvement. When our case was diagnosed, the disease was at Stage I. Some authors make a distinction between both the primary form, which represents metaplasia of cartilage, and a secondary form that is characterized by low cellular atypia.[12] Lexer postulated an overactivity of the embryonic rests at the junction of the synovial membrane and articular cartilage as the cause of chondromatosis.[13]

Radiologic features of disease may vary according to stages of disease; first, there will only be swelling around the involved joint.[14] The most common radiologic finding includes radiopaque free bodies with different sizes.[15] Calcification usually occurs at the last stage and may not be seen in all patients.[16] Intra-articular masses, noncalcified masses, and septate swellings may be differentiated with magnetic resonance imaging (MRI) or computed tomography.[17],[18]

Differential diagnosis of synovial chondromatosis can be many other diseases which may be benign or malignant. Benign lesions such as synovial hemangioma, pigmented villonodular synovitis, and lipoma arborescens and malignant lesions such as synovial chondrosarcoma and synovial sarcoma.[19] Follow-up cases show malignant transformation rarely.[20] Anract et al.[21] reported that malignant transformation is very rare, and this condition should be thought and suspected when there is bone involvement in MRI and a quick progression clinically. If the lesion is large and in elderly patient, more prevalent differential diagnosis should be chondrosarcoma.[22],[23]

Surgery is considered the treatment of choice. The primary prognostic consideration is the possibility of a late recurrence. Some studies have shown that a partial synovectomy with the removal of all loose bodies cannot prevent a late recurrence.[12],[24] Moreover, a review of the literature by von Lindern et al. revealed a high rate of recurrence in cases where total synovectomy has not been performed.[12] Aydin et al. concluded that the stage of the disease is associated with the risk of recurrence, and they proposed a treatment based on stage.[25] The presence of orderly ossification favors a benign course. There are a few reports with sarcomatous change in a nodule requiring radical or total surgery.[26]

Gross appearance is that of a multilobulated synovium with multiple white or bluish nodules that are composed of hyaline cartilage attached to the synovium. These nodules may detach to form loose bodies. Most nodules are small in size; cases of many nodules have been reported, with multiple nodules combining into giant nodules measuring up to 20 cm in size.[27]

Microscopically, the metaplastic synovium shows cartilaginous nodules beneath the surface lining of the synovial membrane with formation of many cartilaginous nodules within the joints, bursae, or tendon sheaths. They may be highly cellular and of moderate pleomorphism. The nodules are variably cellular with the chondrocytes seen in clusters, a very characteristic finding.[28]

Prognostic factors include the entity being self-limiting illness but may recur locally after excision, especially in the early stage of disease. Damage to the joint surface may result in secondary degenerative joint disease. Bone erosion has also been reported in few cases.[2]

  Conclusion Top

Giant SOC with monoarticular involvement is a very rare disease. Clinical diagnosis is very difficult as it commonly mimics malignancy based on large size and rapid progression. Opinion of clinical, radiological, and histological findings should be correlated in every case, and the patient is treated accordingly, thus avoiding a wrong diagnosis and in the benefit of the patient. Hence, we conclude that correlation of biopsy finding is compulsory before coming to diagnosis, and proper diagnosis by histopathology is the only confirmed way in diagnosing such giant cases.

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Conflicts of interest

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  References Top

Murphy FP, Dahlin DC, Sullivan CR. Articular synovial chondromatosis. J Bone Joint Surg Am 1962;44:77-86.  Back to cited text no. 1
Miller MV, King A, Mertens F. Synovial chondromatosis. WHO Tumors of Bone and Soft Tissues. IARC Press. 2002. p. 245.  Back to cited text no. 2
Maurice H, Crone M, Watt I. Synovial chondromatosis. J Bone Joint Surg Br 1988;70:807-11.  Back to cited text no. 3
Fuller E, Bharatha A, Yeung R, Kassel EE, Aviv RI, Howard P, et al. Case of the month #166: Synovial chondromatosis of the temporal mandibular joint. Can Assoc Radiol J 2011;62:151-3.  Back to cited text no. 4
Koyama J, Ito J, Hayashi T, Kobayashi F. Synovial chondromatosis in the temporomandibular joint complicated by displacement and calcification of the articular disk: Report of two cases. AJNR Am J Neuroradiol 2001;22:1203-6.  Back to cited text no. 5
Matsumoto H, Kawakubo M, Otani T, Fujikawa K. Extensive post-traumatic ossification of the patellar tendon. A report of two cases. J Bone Joint Surg Br 1999;81:34-6.  Back to cited text no. 6
Fletcher CD, Unni KK, Mertens F, editors. World Health Organisation Classifi cation of Tumors. Pathology and Genetics of Tumors of Soft Tissue and Bone; 2002. p. 245.  Back to cited text no. 7
Trias A, Quintana O. Synovial chondrometaplasia: Review of world literature and a study of 18 Canadian cases. Can J Surg 1976;19:151-8.  Back to cited text no. 8
Baunsgaard P, Nielsen BB. Primary synovial chondrometaplasia. Histologic variations in the structure of metaplastic nodules. Acta Pathol Microbiol Immunol Scand A 1984;92:455-60.  Back to cited text no. 9
Sviland L, Malcolm AJ. Synovial chondromatosis presenting as painless soft tissue mass – A report of 19 cases. Histopathology 1995;27:275-9.  Back to cited text no. 10
Milgram JW. Synovial osteochondromatosis: A histopathological study of thirty cases. J Bone Joint Surg Am 1977;59:792-801.  Back to cited text no. 11
von Lindern JJ, Theuerkauf I, Niederhagen B, Bergé S, Appel T, Reich RH. Synovial chondromatosis of the temporomandibular joint: Clinical, diagnostic, and histomorphologic findings. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2002;94:31-8.  Back to cited text no. 12
Erich L. Mclvor RR, King D. Osteochondromatosis of the hip joint. J Bone Joint Surg 1962;44A: 87-97.  Back to cited text no. 13
Hsueh CJ, Huang GS, Juan CJ, Wang SG, Liou CH, Hsiao HS, et al. Synovial chondroma of the ankle in a young child after recent trauma: CT and MR features. Clin Imaging 2001;25:296-9.  Back to cited text no. 14
Kural C, Akyildiz MF, Ertürk H, Bayraktar K. Synovial chondromatosis of the ankle joint and elbow in two cases. Acta Orthop Traumatol Turc 2005;39:441-4.  Back to cited text no. 15
Mussey RD Jr., Henderson MS. Osteochondromatosis. J Bone Joint Surg Am 1949;31A:619-27.  Back to cited text no. 16
Narváez JA, Narváez J, Aguilera C, De Lama E, Portabella F. MR imaging of synovial tumors and tumor-like lesions. Eur Radiol 2001;11:2549-60.  Back to cited text no. 17
Yamaguchi T, Naito M, Asayama I, Fujisawa M, Ishiko T, Kambe T, et al. Arthroscopic surgery for synovial chondromatosis of the hip: A report of two cases. J Orthop Traumatol 2003;4:90-1.  Back to cited text no. 18
Wittkop B, Davies AM, Mangham DC. Primary synovial chondromatosis and synovial chondrosarcoma: A pictorial review. Eur Radiol 2002;12:2112-9.  Back to cited text no. 19
Hallam P, Ashwood N, Cobb J, Fazal A, Heatley W. Malignant transformation in synovial chondromatosis of the knee? Knee 2001;8:239-42.  Back to cited text no. 20
Anract P, Katabi M, Forest M, Benoit J, Witvoët J, Tomeno B. Synovial chondromatosis and chondrosarcoma. A study of the relationship between these two diseases. Rev Chir Orthop Reparatrice Appar Mot 1996;82:216-24.  Back to cited text no. 21
Chillemi C, Marinelli M, de Cupis V. Primary synovial chondromatosis of the shoulder: Clinical, arthroscopic and histopathological aspects. Knee Surg Sports Traumatol Arthrosc 2005;13:483-8.  Back to cited text no. 22
Richman JD, Rose DJ. The role of arthroscopy in the management of synovial chondromatosis of the shoulder. A case report. Clin Orthop Relat Res 1990;257:91-3.  Back to cited text no. 23
Jeon IH, Ihn JC, Kyung HS. Recurrence of synovial chondromatosis of the glenohumeraljoint after arthroscopic treatment. Arthroscopy 2004;20:524-7.  Back to cited text no. 24
Aydin MA, Kurtay A, Celebioglu S. A case of synovial chondromatosis of the TMJ: Treatment based on stage of the disease. J Craniofac Surg 2002;13:670-5.  Back to cited text no. 25
Nixon JE, Frank GR, Chambers G. Synovial osteochondromatosis with report of four cases, one showing malignant change. U S Armed Forces Med J 1960;11:1434-45.  Back to cited text no. 26
Serbest S, Kesgin E, Tosun HB. Neglected case of hip joint synovial chondromatosis. Pam Med J 2014;7:167-70.  Back to cited text no. 27
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  [Figure 1], [Figure 2], [Figure 3], [Figure 4]


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