Albert J. Aboulafia

Biopsy of Soft Tissue Masses: Evidence-based Medicine for the Musculoskeletal Tumor Society

AbstractThe literature contains a number of controversies regarding key questions: (1) When is a biopsy indicated? (2) How should the biopsy be placed? (3) How should the biopsy be performed and which has the greatest diagnostic accuracy? (4) Who should perform the biopsy? (5) What clinical parameters present the greatest diagnostic difficulty? Using PubMed and Google Scholar we performed English-language literature searches of clinical studies reporting biopsy of soft tissue masses. Thirty-two studies met the inclusion criteria but were only able to address three of the five questions the authors had hoped to evaluate. Available evidence suggests open biopsy has the highest diagnostic accuracy over core needle biopsy, which was higher than fine needle aspiration. There was no evidence to address who is best suited to perform the biopsy (general surgeon, orthopaedic surgeon, radiologist, pathologist) in terms of accuracy of diagnosis. Frozen section at the time of biopsy may improve diagnostic accuracy. Diagnostic difficulty was associated with myxoid and round cell neoplasms, infections, and tumors located in the paraspinal region. The limited number of references addressing these issues demonstrated the need for more Level I research in the area of biopsy of soft tissue masses. Level of Evidence: Level III, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Soft tissue mass in a 5-year-old boy

A 5-year-old otherwise healthy boy presented with a painless mass on the proximal medial aspect of the right leg. His father first noticed the mass 2 weeks before presentation. There was no history of trauma to the area and there were no associated constitutional symptoms of fever, chills, night sweats, or weight loss. The patient’s medical history and family history were unremarkable. There was no family history of cancer. His childhood development was unremarkable and developmental milestones had been achieved at appropriate times.

Prereferral evaluation of patients with suspected bone and soft tissue tumors.

One hundred consecutive patients referred to an orthopaedic oncology practice for evaluation of suspected bone or soft tissue tumors were studied prospectively. There were 76 patients with bone lesions and 24 patients with soft tissue lesions. At the time of initial consultation, information regarding the referring diagnosis, number of prior physician office visits, and prereferral imaging studies obtained was collected. There were 50 patients with benign tumors, 17 patients with primary malignant tumors, 11 patients with metastatic tumors, and 22 patients with nonneoplastic conditions. The average number of physician visits before referral for the entire group was 4.8 visits and was highest for patients with malignant bone tumors (6.2 visits). Imaging studies obtained before referral included plain radiographs, magnetic resonance imaging, bone scans, computed tomography scans, and ultrasound. None of the plain radiographs were thought to be unnecessary; however, 26 of 76 (34.2%) magnetic resonance imaging scans, 17 of 40 (42.5%) bone scans, and 13 of 36 (36.1%) computed tomography scans were excessive and did not contribute to the evaluation of the lesion. Although only 58% of the study group included patients with benign bone tumors and nonneoplastic bone lesions, they accounted for the majority (79%) of unnecessary imaging studies. Primary care physicians and general orthopaedic physicians were equally likely to order unnecessary imaging studies (48% and 52%, respectively).

Desmoid Cell Motility Is Induced In Vitro by rhEGF

Desmoid tumors are benign but locally invasive myofibroblastic lesions that arise predominantly in the abdominal wall or shoulder and are prone to aggressive local recurrences. A perceived association between desmoid activity and the expression of growth factors during pregnancy or following trauma suggests a cause‐and‐effect relationship between growth factor stimulation and desmoid invasiveness. We used Boyden Chambers to quantify cell motility in order to determine the effect of growth factor stimulation on desmoid cell migration. Desmoid cell cultures were treated under serum‐free conditions with epidermal growth factor (rhEGF) or transforming growth factor alpha (rhTGFα). Additional cell cultures were pretreated under serum‐free conditions with the EGF receptor (EGFR) inhibitor AG1478, alone or in combination with the TGFβ1 receptor inhibitor SB431542, and then stimulated with growth factor prior to being assayed for cell motility. The experiments demonstrated a direct dose‐dependent relationship between rhEGF stimulation and desmoid motility. In contrast, rhTGFα was less effective at inducing cell migration. rhEGF‐induced cell migration could be diminished, but not reduced to control levels, by inhibiting EGFR. When EGF and TGFβ1 receptors were inhibited simultaneously, the level of rhEGF‐induced cell migration was reduced significantly beyond the level of cell migration generated by inhibition of EGFR alone.

FAP-associated desmoid invasiveness correlates with in vitro resistance to doxorubicin

Desmoid tumors are locally invasive myofibroblastic lesions that arise predominantly in the abdominal wall or shoulder girdle and are prone to aggressive local recurrences without metastases. We hypothesized the intrinsic invasiveness and drug resistance displayed by cells derived from a familial adenomatous polyposis (FAP)-associated desmoid tumor would surpass the response shown by cells derived from sporadic desmoid tumors. In vitro cell motility and expression of motility-associated genes were quantified using Boyden Chambers and Enzyme-Linked ImmunoSorbent Assays, respectively. Doxorubicin resistance was quantified by Trypan Blue dye exclusion. cDNA microarrays identified genes responsive to doxorubicin. FAP-associated tumor cells were significantly more invasive and refractory to doxorubicin than were cells extracted from sporadic tumors. Pro-MMP1 protein predominated over MMP3 in FAP-associated cell culture supernatants, while MMP3 was the dominant antigen in sporadic tumor cell supernatants. Three genes associated with apoptosis were identified by microarray, two prosurvival genes overexpressed in FAP-associated cell cultures (NTN1, TNFRSF10C) and one proapoptosis gene overexpressed in sporadic tumor cell cultures (FOXL2).

Fas Death Pathway in Sarcomas Correlates with Epidermal Growth Factor Transcription

Modulation of apoptosis may influence sarcoma pathogenesis and/or aggressiveness. The Fas death pathway, mediated by FasL or TGFβ, is one of two apoptotic pathways. Recent studies report that EGF can modulate TGFβ and/or FasL expression/activity; thus, EGF has the potential to influence activation of the Fas pathway. EGF is not always detectable in mesenchymal tumors; therefore, we hypothesized EGF would define which Fas ligand predominates. We assayed 57 surgically removed human sarcomas for 10 genes involved in the Fas pathway. Skeletal muscle biopsies from eight patients served as controls. Sample transcripts were detected by real-time RT-PCR. We attempted to identify relevant predictor variables. The 57 sarcomas were segregated into two categories defined by EGF mRNA content: (1) 23 tumors with EGF concentrations that approximated muscle EGF transcript levels (high-EGF tumors); and (2) 34 tumors that either lacked EGF mRNA, or whose mRNA levels were very low and frequently undetected by PCR (low-EGF tumors). TGFβ1 expression best predicted Fas transcript concentrations in the 34 low-EGF sarcomas, while FasL predicted Fas mRNA levels in the remaining 23 high-EGF sarcomas. The results suggest ligand activity in the Fas death pathway correlates with EGF transcription in sarcomas.

Oncogene coexpression in mesenchymal neoplasia correlates with EGF transcription.

Epidermal growth factor (EGF) is a potent mitogenic factor for cells of mesodermal and ectodermal origin, and its over-expression is associated with a variety of cancers. We asked whether oncogene coexpression occurs in mesenchymal neoplasms, if coexpression correlates with EGF transcription, and whether coexpression can be attributed to the EGF-induced overexpression of oncogenes. We quantified the mRNA concentrations of EGF and 14 oncogenes in 42 primary sarcomas, 31 benign tumors, and 10 skeletal muscle controls, and compared mRNA concentrations and gene pair correlations in EGF positive (EGF[+]) tumors to transcript concentrations and correlations in EGF negative (EGF[−]) tumors. Transcripts were detected by real time reverse transcription-polymerase chain reaction. Pearsons correlation coefficients identified gene associations, and gene synchrony associated with EGF expression was evaluated using chi square. Transcript concentrations in tumors were compared graphically and with t tests. Gene correlations predominated in EGF[+] benign tumors and in EGF[−] primary sarcomas. The dichotomy in oncogene coexpression evident in benign and malignant tumors could not be attributed to statistical differences in mRNA content between EGF[+] and EGF[−] tumors. EGF may enhance, or may indicate the presence of, oncogene coexpression in benign mesenchymal lesions, but counters gene synchronization in sarcomas.

Potential for functional redundancy in EGF and TGFα signaling in desmoid cells: a cDNA microarray analysis

Genes that replace or duplicate the function of other genes are considered functionally redundant. In this cDNA microarray study, using an Agilent microarray platform and GeneSifter™ analysis software, we evaluated (1) the degree of downstream transcriptional redundancy and (2) the level of genetic uniqueness apparent in desmoid tumor cells stimulated in vitro for 3 h or for 24 h with 100 ng/ml of exogenous recombinant human EGF (rhEGF) or with recombinant human transforming growth factor alpha (rhTGFα). Our intent was to identify genes costimulated, or genes unique to, desmoid cells stimulated in vitro with rhEGF and rhTGFα. This experimental approach demonstrated a 55% transcriptional redundancy in the number of desmoid genes significantly upregulated or downregulated following 3 h of stimulation with rhEGF or with rhTGFα, and a 65% transcriptional redundancy following 24 h of growth factor stimulation. Approximately 150 genes costimulated by rhEGF and rhTGFα were identified. This study suggests that EGF and TGFα retain some level of functional redundancy, possibly resulting from their divergence from a common ancestral gene.