Advances in molecular characterization and targeted therapy in dermatofibrosarcoma protuberans

COL1A1::PDGFB fusion-associated uterine sarcoma and response to Imatinib: A case report

Uterine sarcomas are rare neoplasms of the uterus, some of which are associated with distinctive gene fusions. COL1A1::PDGFB fusion uterine sarcoma is a recently described entity that shares the same genetic alteration as dermatofibrosarcoma protuberans. These uterine sarcomas have a nonspecific spindle cell sarcoma appearance and are CD34 positive by immunohistochemistry. Accurate diagnosis relies on identification of the characteristic fusion by molecular genetic methods. The importance of diagnosing this entity lies in its potential response to targeted therapy with imatinib, a tyrosine kinase inhibitor successfully used in dermatofibrosarcoma protuberans, but only one prior case of COL1A1::PDGFB fusion uterine sarcoma treated with imatinib has been reported. Here, we describe a case of COL1A1::PDGFB fusion uterine sarcoma with response to imatinib after recurrence, with a brief review of this rare tumor.

A unique case of Dermatofibrosarcoma Protuberans arising from an inguinal hernial repair scar in a Middle Eastern male - A Case Report

INTRODUCTION AND IMPORTANCE

Dermatofibrosarcoma Protuberans (DFSP) is a rare and fatal variant of Spindle Cell Sarcoma. It has an annual incidence rate of 0.8 to 4.5 cases per one million individuals. It's locally aggressive and has vague and masquerading clinical presentations. Misdiagnosis is devastating as it can lead to time wasting, expenditure of unnecessary resources, and possibly raise morbidity and mortality for patients. It is warranted to raise preoperative clinical awareness to achieve prompt surgical therapeutic interventions to reach an up-to-par prognosis.

CASE PRESENTATION

We demonstrate the case of a 50-year-old previously healthy Middle Eastern male patient, who was referred to our General Surgery clinic with the chief complaint of an expansive bulge in his left iliac fossa. Preoperative imaging could not exclude a neoplastic cause behind the presentation. Based on the clinical picture, a surgical intervention was decided.

CLINICAL DISCUSSION

Our patient's treatment was consummated by means of classical surgical resection of the lesion with adequate negative margins and referring him to an oncologist specialized in DFSP to undergo the necessary adjuvant treatment. Definitive diagnosis was firmly entrenched postoperatively after finalization of the histopathological and immunohistochemical analyses of the resected protuberance.

CONCLUSION

DFSP is an eminently rare entity, especially DFSPs which originate from a surgical scar -as was our patient's- and fluctuates in its clinical presentation, thus, it is our responsibility to depict, study this malignant tumor, and document its incidence, so that we can make ironclad clinical decrees to plummet the morbidity and mortality of this relentless neoplasia.

Recurrent Giant Cell Fibroblastoma in an Infant: A Diagnostic Challenge

Background: Giant cell fibroblastoma (GCF) shows a wide spectrum of morphological patterns which may lead to a misdiagnosis of sarcoma. Case Report: This 14- month- old baby was referred to us for recurrent left scrotal embryonal rhabdomyosarcoma (ERMS), first diagnosed at 8 months, status post chemotherapy. Review of previous histology, cytology (with frequent multinucleated floret type giant cells but without cross striations) and immunohistochemistry resulted in the change of diagnosis to GCF. It was re-excised, recurred at 20 months of age, and was again re-excised. The morphology was the same in both recurrences as the original. Conclusion: Despite chemotherapy, the histology of multiple recurrences for GCF remained the same as the original. Cytologically, identification of the multinucleated floret like giant cells without cross striations was helpful in differentiating this lesion from embryonal rhabdomyosarcoma.

Use of Fluorescence In Situ Hybridization (FISH) in Diagnosis and Tailored Therapies in Solid Tumors

Fluorescence in situ hybridization (FISH) is a standard technique used in routine diagnostics of genetic aberrations. Thanks to simple FISH procedure is possible to recognize tumor-specific abnormality. Its applications are limited to designed probe type. Gene rearrangements e.g., ALK, ROS1 reflecting numerous translocational partners, deletions of critical regions e.g., 1p and 19q, gene fusions e.g., COL1A1-PDGFB, genomic imbalances e.g., 6p, 6q, 11q and amplifications e.g., HER2 are targets in personalized oncology. Confirmation of genetic marker is frequently a direct indication to start specific, targeted treatment. In other cases, detected aberration helps pathologists to better distinguish soft tissue sarcomas, or to state a final diagnosis. Our main goal is to show that applying FISH to formalin-fixed paraffin-embedded tissue sample (FFPE) enables assessing genomic status in the population of cells deriving from a primary tumor or metastasis. Although many more sophisticated techniques are available, like Real-Time PCR or new generation sequencing, FISH remains a commonly used method in many genetic laboratories.

Treatment-related adverse effects with pazopanib, sorafenib and sunitinib in patients with advanced soft tissue sarcoma: a pooled analysis

Objective

Research efforts have investigated therapies targeting tyrosine kinase signaling pathways. We performed a pooled analysis to determine the frequency of severe adverse effects in patients with soft tissue sarcoma treated with pazopanib, sorafenib and sunitinib.

Materials and methods

We performed a comprehensive search of PubMed, Web of Science, Ovid, the Cochrane Library and Embase databases from the drugs’ inception to May 2017 to identify clinical trials. All-grade and severe adverse events (AEs; grade≥3) were analyzed.

Results

A total of 10 trials published between 2009 and 2016, including 843 patients, were eligible for analysis. We included 424 patients (three studies) who received pazopanib 800 mg daily, 353 patients (five studies) who received sorafenib 400 mg twice daily and 66 patients (two studies) who received sunitinib 37.5 mg daily. The incidence of AEs is different among the three VEGFR-tyrosine kinase inhibitors (TKIs). Pazopanib showed higher incidence of all-grade nausea, diarrhea and hypertension compared with sorafenib and sunitinib. However, patients in the sorafenib group experienced a significantly higher frequency of all-grade rash (26.1%), hand–foot syndrome (33.4%) and mucositis (38.5%). The difference was highly significant for sorafenib vs. pazopanib in the incidence of all-grade rash (odds ratio [OR] 1.649, 95% CI 1.086–2.505, P=0.023), hand–foot syndrome (OR 3.096, 95% CI 1.271–7.544, P=0.009) and mucositis (OR 4.562, 95% CI 2.132–9.609, P<0.001). Moreover, the frequency of grade ≥3 mucositis was significantly higher in the sunitinib group compared with the pazopanib or sorafenib group (7.6% vs. 1.3%, OR 6.448, 95% CI 1.499–27.731, P=0.013).

Conclusion

Statistically significant differences in certain common adverse effects, such as all-grade and severe AEs, were detected among pazopanib, sorafenib and sunitinib in the current study. Early and prompt management is critically needed to avoid unnecessary dose reductions and treatment-related discontinuations.

Appropriate use criteria in dermatopathology: Initial recommendations from the American Society of Dermatopathology

BACKGROUND

Appropriate use criteria (AUC) provide physicians guidance in test selection, and can affect health care delivery, reimbursement policy, and physician decision-making.

OBJECTIVES

The American Society of Dermatopathology, with input from the American Academy of Dermatology and the College of American Pathologists, sought to develop AUC in dermatopathology.

METHODS

The RAND/UCLA appropriateness methodology, which combines evidence-based medicine, clinical experience, and expert judgment, was used to develop AUC in dermatopathology.

RESULTS

With the number of ratings predetermined at 3, AUC were developed for 211 clinical scenarios involving 12 ancillary studies. Consensus was reached for 188 (89%) clinical scenarios, with 93 (44%) considered "usually appropriate" and 52 (25%) "rarely appropriate" and 43 (20%) having "uncertain appropriateness."

LIMITATIONS

The methodology requires a focus on appropriateness without comparison between tests and irrespective of cost.

CONCLUSIONS

The ultimate decision to order specific tests rests with the physician and is one where the expected benefit exceeds the negative consequences. This publication outlines the recommendations of appropriateness-the AUC for 12 tests used in dermatopathology. Importantly, these recommendations may change considering new evidence. Results deemed "uncertain appropriateness" and where consensus was not reached may benefit from further research.

Dermatofibrosarcoma Protuberans in a Patient With Cowden Syndrome: Revisiting the PTEN and PDGF Pathways

PTEN hamartoma tumor syndrome, of which Cowden syndrome (CS) is the most recognized variant, is characterized by multiple benign and malignant tumors of ectodermal, mesodermal, and endodermal origins, secondary to germline mutation in the phosphatase and tensin homolog (PTEN) gene. Dermatofibrosarcoma protuberans (DFSP) is a locally aggressive malignant fibroblastic/myofibroblastic tumor of the skin, characterized by the t(17:22)(q22:q13) translocation resulting in fusion of the COL1A1 and PDGFB genes. An association between CS and DFSP has not been reported in the literature to date. The authors have encountered a male patient with CS and a history of DFSP that developed adjacent to a sclerotic fibroma on the parietal scalp, both excised at age 7. He presented at age 21 with an enlarging pink nodule at the same site on the parietal scalp. Excision revealed a dermal and subcutaneous storiform spindle cell proliferation with fat entrapment and positive staining for CD34, consistent with DFSP. Fluorescence in situ hybridization confirmed PDGFB gene rearrangement. PTEN expression in the patient's recurrent DFSP was nearly absent when compared with that of sporadic DFSP. To our knowledge, this is the first report of DFSP in a patient with CS. Although the association is likely to be coincidental, the authors revisited the PTEN and the PDGF pathways to speculate any possible interplay of the 2 conditions on a molecular level.

Dermatofibrosarcoma Protuberans: A Rare Malignancy of the Breast

Dermatofibrosarcoma protuberans (DFSP) of the breast is a rare skin cancer with only a few cases reported in the literature. It corresponds to approximately 1% of all soft tissue sarcomas and to less than 0.1% of all malignancies with annual incidence of 0.8-4.5 cases per million. DFSP usually affects young and middle-aged adults and it can affect any site, but most commonly the trunk and extremities. This tumor arises from the deep dermis and subcutaneous tissues and is usually locally aggressive, but rarely metastasizes. Surgery including wide local excision with free margins remains the main modality of treatment. We report a case in a 28-year-old Omani woman who presented with a right breast lump to a local secondary hospital. She was offered excision biopsy of the lump and the histology came as DFSP with involved margins. The patient was then referred to the Breast Unit at the Royal Hospital where she was reviewed by multidisciplinary team including breast surgeons, oncologists, radiation oncologists, pathologists, and breast radiologists. Her laboratory and radiological investigations did not show any signs of distal metastasis and breast ultrasound did not reveal any residual breast lesions. We performed a wide re-excision of the previous surgical scar with the underlying breast tissues down to the level of the pectoral fascia followed by treatment with radiotherapy. The final histology report showed the presence of a 4×5mm residual tumor, and all resection margins were tumor-free. At six months follow-up, she had no signs of local recurrence. We publish this case report because of its rarity.

Current treatment options for dermatofibrosarcoma protuberans

Dermatofibrosarcoma protuberans (DFSP) is rare, infiltrating dermal neoplasm, characterized by indolent growth and low probability of metastases. The critical event in DFSP development is the rearrangement of chromosome 17 and 22, leading to transcriptional up-regulation of platelet-derived growth factor, providing an autocrine and/or paracrine stimulus. The cornerstone of treatment for localized DFSP is complete surgical resection with microscopically negative margins. Adjuvant radiotherapy is suggested in cases of positive margins when re-excision is not feasible. The first effective systemic therapy in DFSP introduced into clinical practice was imatinib, demonstrating dramatic activity in advanced cases. Current results indicate that some DFSP patient initially evaluated as unresectable/metastatic or necessitating mutilating surgery turned resectable after imatinib therapy and this rational approach leading to complete remission maybe potentially curative. The clinical experience with other tyrosine kinase inhibitors is limited and imatinib remains the gold standard treatment of locally unresectable/metastatic DFSP. This review summarizes state of the art and perspectives on the DFSP management.

Dermatofibrosarcoma protuberans of penis: Case report and literature review

Dermatofibrosarcoma protuberans (DFSP) is a rare mesenchymal skin tumor with intermediate to low grade malignancy and occasional distant metastasis and high rate of recurrence locally. It mostly involves trunk, extremities, scalp, and neck. This article describes a middle-aged married male with a DFSP lesion involving ventral aspect of glans and distal shaft of penis who underwent local excision and primary closure. The patient was tumor-free at three years of follow-up.

Erdheim-Chester disease: characteristics and management

Erdheim-Chester disease is a rare CD68(+), CD1a(-) non-Langerhans cell histiocytosis with multiorgan involvement. The etiology of Erdheim-Chester disease is unclear; there are no known associated infectious or hereditary genetic abnormalities. However, somatic BRAF mutations have recently been identified in these patients. Historically, the literature regarding the management of Erdheim-Chester disease consisted of case reports and small case series with anecdotal therapeutic responses to agents including, but not limited to, cytotoxic chemotherapy, bone marrow transplantation, cladribine, corticosteroids, IFN-α, the BCR-ABL/KIT inhibitor imatinib mesylate, the IL-1 receptor antagonist anakinra, the TNF-inhibitor infliximab, and recently the BRAF inhibitor vemurafenib. We performed a search of the literature using PubMed with the terms Erdheim Chester disease, without date limitations, including case reports, case series, original articles, and previous review articles. In the absence of large-scale studies, experience-based management prevails. The present review details our approach to the management of patients with Erdheim-Chester disease.

Dermatofibrosarcoma protuberans: a case report

We present a typical case of dermatofibrosarcoma protuberans with local recurrence 2 months after surgery and, motivated by this patient, make a review of the most important aspects. This is a rare tumor and we call special attention to the fact that its recurrence is extremely frequent, so there is absolute need to observe these patients periodically after surgery.

Complete resection of recurrent and initially unresectable dermatofibrosarcoma protuberans downsized by Imatinib

Curative surgical treatment of recurrent, locally advanced dermatofibrosarcoma protuberans is often limited owing to a close relation of the tumor with important anatomical structures. Targeted therapy with imatinib, a tyrosine kinase inhibitor, may cause significant reduction of tumor volume, thereby enabling radical surgery. This treatment strategy, therefore, offers a chance of cure for selected patients with advanced dermatofibrosarcoma protuberans. In addition, preoperative treatment with imatinib may decrease possible disfigurement related to radical surgery for large tumors.

PDGFB rearrangement in dermatofibrosarcoma protuberans: correlation with clinicopathologic characteristics and clinical implications

Dermatofibrosarcoma protuberans (DFSP) is characterized genetically by the translocation t(17;22)(q22;q13), which creates a COL1A1/PDGFB fusion gene. The implications of this gene for the clinicopathologic features of the disease are not fully understood. Fifty-one cases of DFSP from 46 patients were reclassified as DFSP (n=29) and DFSP-fibrosarcomatous variant (DFSP-FS; n=22). Fluorescence in situ hybridization was performed using a dual-color break-apart probe to detect rearrangements involving PDGFB, and CD34 immunohistochemistry staining was done. The DFSP-FS was found in older patients, and the tumors were larger, with a smaller mean area of staining for CD34. PDGFB rearrangement was found in 45 cases (95.7%). The mean gene copy number was 3.82 (range 2.2-6.45) and was higher in DFSP-FS than in classic DFSP (4.54 vs. 3.47; P < .001). The PDGFB copy number showed a moderate positive correlation with the number of mitotic figures and tumor size. Patients undergoing wide excision or having no involvement of the resection margin had no relapses. These results suggest a role for COL1A1/PDGFB in sarcomatous change in DFSP over time. Detection of COL1A1/PDGFB rearrangement by fluorescence in situ hybridization is useful for confirmation of the diagnosis. Patients who present with metastatic DFSP-FS show less typical histologic findings and loss of CD34 staining, leaving PDGFB rearrangement as the preferred adjunctive method for diagnosis from small biopsies and for prediction of the value of imatinib therapy.

Atrophic dermatofibrosarcoma protuberans: report of a case demonstrated by detecting COL1A1-PDGFB rearrangement

Dermatofibrosarcoma protuberans is a locally aggressive mesenchymal neoplasm. It usually presents as an indurated plaque that protrudes above the surface of the skin. Some patients have clinically persistent plaques that might be atrophic. The atrophic variant of dermatofibrosarcoma protuberans may be confused with some common skin diseases with atrophic appearance. We reported a 40-year-old woman who had a 10-year history of an atrophic dermatofibrosarcoma protuberans. Molecular analysis showed a fusion between COL1A1 exon 31 to exon 2 of PDGFB. The lesion was totally excised, with negative margins of the resection demonstrated by CD34 immunostaining. To our knowledge, this is the second case of atrophic dermatofibrosarcoma protuberans confirmed by detection of COL1A1-PDGFB fusion gene. This appears to be the first report of a fusion between COL1A1 exon 31 to exon 2 of PDGFB in atrophic dermatofibrosarcoma protuberans.

Atrophic dermatofibrosarcoma protuberans

BACKGROUND

Dermatofibrosarcoma protuberans (DFSP) is an uncommon malignant mesenchymal tumor that arises in the dermis and is characterised by latency in its initial detection. As a rare form, atrophic or morphea-like DFSP has been documented. Atrophic DFSP resemble other benign lesions such as morphea, idiopathic atrophoderma, atrophic scar, anetoderma or lipoatrophy. It behaves like classic DFSP. It commonly favours young to middle aged adults. It has a slow infiltrative growth and a high rate of local recurrence if not completely excised. Metastases are rare and occur after repeated local recurrence. Surgical excision is the best line of treatment. Long term follow up is required to detect recurrence.

MAIN OBSERVATIONS

We report a case of atrophic DFSP in a 52-year-old female patient. Diagnosis was achieved according to clinical, histopathological and immunohistochemical findings. Tumor was surgically excised with safety margin and the patient is still under follow up.

CONCLUSIONS

Atrophic DFSP is a rare variant of DFSP. It is a tumor of low to moderate grade malignancy. Surgical excision is the best line of management. Long term follow up is necessary.

Searching for molecular targets in sarcoma

Sarcoma are about 1% of cancers. Within that 1% are widely varied tumors now divided into types and subtypes. Sarcoma occur in patients of all ages with frequency spread evenly over the human age range. Although the specific cell of origin of many sarcoma remains unclear, sarcoma are all tumors of mesenchymal origin. The mesenchymal stem cell, a pluripotent cell, which gives rise to varied differentiated cells including osteocytes, adipocytes, chondrocytes, muscle cells, fibroblasts, neural cells and stromal cells, is the most likely ultimate cell of origin for sarcoma. When mesenchymal stem cell genetics go awry and malignant transformation occurs sarcoma including osteosarcoma, Ewing's sarcoma, chondrosarcoma, rhabdomyosarcoma, synovial sarcoma fibrosarcoma, liposarcoma and many others can initiate. Our knowledge of sarcoma genetics is increasing rapidly. Two general groups, sarcoma arising from chromosomal translocations and sarcoma with very complex genetics, can be identified. Genes that are frequently mutated in sarcoma include TP53, NF1, PIK3CA, HDAC1, IDH1 and 2, KDR, KIT and MED12. Genes that are frequently amplified in sarcoma include CDK4, YEATS4, HMGA2, MDM2, JUN, DNM3, FLT4, MYCN, MAP3K5, GLI1 and the microRNAs miR-214 and miR-199a2. Genes that are upregulated in sarcoma include MUC4, CD24, FOXL1, ANGPTL2, HIF1α, MDK, cMET, TIMP-2, PRL, PCSK1, IGFR-1, TIE1, KDR, TEK, FLT1 and several microRNAs. While some alterations occur in specific subtypes of sarcoma, others cross several sarcoma types. Discovering and developing new therapeutic approaches for these relentless diseases is critical. The detailed knowledge of sarcoma genetics may allow development of sarcoma subtype-targeted therapeutics.