Successful correction of tibial bone deformity through multiple surgical procedures, liquid nitrogen-pretreated bone tumor autograft, three-dimensional external fixation, and internal fixation in a patient with primary osteosarcoma: a case report

Reconstruction using a frozen autograft for a skull and humeral lesion of synchronous multicentric osteosarcoma after undergoing successful neoadjuvant chemotherapy: a case report and review of the literature

Background

Synchronous multicentric osteosarcoma (SMOS) is a rare disease characterized by simultaneous multicentricity of intraosseous osteosarcoma without visceral involvement. SMOS, including a skull lesion, which occurs relatively rarely, and reconstruction using a frozen autograft after the excision of a lesion of SMOS has been infrequently reported previously.

Case presentation

We report an 18-year-old girl with SMOS, with lesions located in the left distal femur, right proximal humerus, and left occipital bone. Her major complaint was pain and swelling around the left knee joint. Asymptomatic lesions of the humerus and skull bone were detected on a systemic bone scan. No visceral organ metastasis was observed. A biopsy of the distal femoral lesion revealed osteosarcoma. Based on the histological findings, multiple bone lesions, and absence of visceral lesion, the clinical diagnosis of SMOS was made. After five courses of neoadjuvant chemotherapy with a regimen of doxorubicin and cisplatin, reconstruction using a tumor prosthesis following wide excision of the left distal femur was performed, and total necrosis was histologically observed in the retracted specimen. Following three cycles of adjuvant chemotherapy, tumor excision and reconstruction with a frozen autograft treated with liquid nitrogen was conducted for both lesions of the humerus and skull, rather than tumor prosthesis or synthetics, in order to retain a normal shoulder function, and to obtain a good cosmetic and functional outcome after treatment of the skull lesion. Further adjuvant chemotherapy could not be administered after the completion of the surgical treatment for all lesions because the adverse events due to chemotherapy were observed. At over 5 years after the diagnosis, she remains clinically disease-free.

Conclusions

An early correct diagnosis, the proper management of chemotherapy, and surgical treatment for all lesions are essential for achieving a good clinical outcome, even in SMOS including a skull lesion. By performing reconstruction using a frozen autograft for a proximal humeral lesion and a skull lesion after confirming the good histological efficacy of neoadjuvant chemotherapy for the primary lesion, the excellent function of the shoulder joint and a good cosmetic outcome at the site of the skull lesion was acquired without complications or recurrence.

Impacts of Tumor Location, Nature and Bone Destruction of Extremity Osteosarcoma on Selection of Limb Salvage Operative Procedure

OBJECTIVE

To study the impacts of tumor location, nature and extent of bone destruction on selection of operative protocol for extremity osteosarcoma (OS).

METHODS

The medical records of 201 patients with extremity OS treated in our institute from December 1999 to June 2014 were retrospectively reviewed. Ninety eligible patients (56 males and 34 females) of average age 20 ± 11 years (range, 4-40 years) were enrolled. Tumor locations were categorized as diaphyseal (4; diaphysis group) or juxta-articular (86); the latter being subclassified as with (51, type III, epiphysis group) or without invasion beyond the epiphyseal line or plate (35, type I and II, metaphysis group) according to MRI images. Tumor nature (osteogenic, 51; osteolytic, 39) was determined radiologically. Extent of bone destruction was quantitated according to Mirel's scoring system to obtain an "invasion score". Regular postoperative follow-up included physical examination and imaging evaluation.

RESULTS

Fifty-four patients underwent biological reconstruction and 36 mechanical reconstruction. The mean follow-up duration was 51 months (range, 6-176 months, including four deaths within 12 months). Biological reconstruction was performed more frequently in the diaphysis and metaphysis groups (31/39, 79.5%) than mechanical reconstruction (8/39, 20.5%, P < 0.05). Biological reconstruction and articular preservation were associated with more satisfactory limb function (MSTS scores: 25.0 ± 3.3 and 25.1 ± 3.6) than mechanical reconstruction and articular resection (MSTS scores: 23.4 ± 3.7 and 23.1 ± 3.4, P < 0.05). Reconstruction methods and articular preservation had no relationship with overall or tumor-free survival (P > 0.05). Osteolytic lesions were associated with more extensive bone destruction than osteogenic lesions according to invasion scores (P < 0.05). Following biological reconstruction, high invasion scores (>8) had a 13.5-fold risk of fracture compared with low scores (≤8) (P < 0.05). Twenty-one subjects had recurrences, 30 metastases and 26 died. Postoperative complications included infection (6), fracture (10), and prosthesis loosening (4). Kaplan-Meier analysis indicated 5- and 10-year survival rates of 68.9% and 62.8%, respectively, and 5- and 10-year tumor-free survival rates of 66.7% and 57.8%, respectively.

CONCLUSION

Selection of limb salvage operative protocol for extremity OS should rely on tumor location, nature and extent of bone destruction. Regardless of tumor site, mechanical reconstruction is indicated for tumors with high invasion scores (>8), whereas biological reconstruction is preferred for those with low invasion scores (≤8). Tumors sparing the epiphyseal line or plate are ideal candidates for articular preservation.

Downregulation of coding transmembrane protein 35 gene inhibits cell proliferation, migration and cell cycle arrest in osteosarcoma cells

Osteosarcoma (OSA) is the most common primary tumor of the bone. Resistance to chemotherapy and the fast rapid development of metastatic lesions are major issues responsible for treatment failure and poor survival rates in OSA patients. Tetraspanins comprise a family of transmembrane receptor glycoproteins that affect tumor cell migration through tetraspanin-integrin interaction. The present study focused on a four-pass transmembrane protein gene, transmembrane protein 35 (TMEM35) gene, and examined its role in the growth, migration and cell cycle progression of OSA cells. In addition, the study discussed whether the TMEM35 gene, which encodes the TMEM35 protein, may be a potential therapeutic target for OSA. In the current study, reverse transcription-quantitative polymerase chain reaction was performed to examine TMEM35 expression in OSA and matched healthy tissues. Small interfering RNAs (siRNAs) were transfected into SaOS2 and U2OS cells to knockdown the TMEM35 expression. Soft-agar colony formation assay was performed to evaluate cell growth, and cell cycle progression was analyzed by flow cytometry. Wound-healing and Boyden chamber assays were also performed to investigate cell invasion and migration by the SaOS2 and U2OS cells. TMEM35 protein was analyzed in a functional protein interaction networks database (STRING database) to predict the functional interaction partner proteins of TMEM35. The results indicated that TMEM35 was abnormally expressed in OSA tissues. Of the 37 examined patients, TMEM35 expression was significantly increased in the OSA tissues of 24 patients (64.86%; P<0.05), when compared with the expression in normal tissues. Furthermore, TMEM35 knockdown following transfection with siRNAs inhibited the colony formation ability of SaOS2 and U2OS cells in soft agar. Flow cytometric analysis also revealed that TMEM35 knockdown by RNA interference may result in G1 phase arrest and a decreased cell population at the S phase. TMEM35 knockdown inhibited cell migration in SaOS2 and U2OS cells in wound-healing assays. In conclusion, TMEM35, a member of the tetraspanin family, serves an important role in the growth of OSA cells.