Neoadjuvant isolated limb perfusion in newly diagnosed untreated patients with locally advanced soft tissue sarcomas of the extremities: the Gustave Roussy experience.

BACKGROUND: Limb-sparing surgery in locally advanced soft tissue sarcomas (LA STS) is challenging. The aim of this study is to evaluate upfront isolated limb perfusion (ILP) in untreated patients with LA STS. METHODS: All consecutive patients with LA STS of the limbs deemed borderline or unresectable and treated with upfront ILP as induction treatment between 2003 and 2016 were included. Demographic, clinical and long-term characteristics were obtained and retrospectively analyzed. RESULTS: 41 patients (pts), with a median age of 51 years [range 21-76], were identified (lower limb 68%, upper limb 32%). Liposarcoma and undifferentiated pleomorphic sarcoma were the most common subtypes (27% and 22%, respectively). Acute toxicities, using Wieberdink classification, were grade II (35 pts, 85%), grade III (2 pts, 5%) and no grade IV-V. Local control rate was 98%. 32 pts had limb-sparing surgery (78%). 1 pt had an early amputation due to progressive disease after ILP. 8 pts were not operated (four had RT alone, one had distant metastases, two had a complete response and one died 3 months after ILP of a pulmonary embolism). 36 pts (84%) received postoperative RT. After a median follow-up of 43 months, 18 pts (47%) relapsed. Median disease-free survival (DFS) was 6.7 years. The median overall survival (OS) was not reached. The 1-year, 5-year and 10-year DFS and OS rates were, respectively, 75%, 50% and 45%, and 90%, 63% and 55%. CONCLUSION: Upfront ILP is an efficient and well-tolerated limb-sparing procedure in borderline or unresectable LA STS without hampering OS.

Working Together and Being Physically Active Are Not Enough to Advise Uniformly and Adequately Low Back Pain Patients: A Cross-Sectional Study.

The profession of the health-care providers (HCPs) influences their recommendations to the patients. Conversely, interdisciplinarity seeks to challenge such differences, so that the patient receives one single and consistent therapeutic message. Some studies also suggest associations between HCPs life habits and recommendations. Our hypotheses were (1) that despite interdisciplinary work, the profession remains a predictor of recommendations and (2) that HCPs who are more physically active recommend more activity. Three clinical vignettes were presented to a group of experts of low back pain (LBP) (guidelines), and 20 physicians, 22 physiotherapists, and 23 nurses to assess how they evaluate the symptoms and pathologies of LBP patients and how much work and physical activity they recommend. Physical activity was assessed with accelerometers and questionnaires. Some interprofessional differences remained present within an interdisciplinary team. The nurses were more restrictive and further away from the guidelines. The physicians were the most in line with them. The physiotherapists recommend as much physical activity, but less work activity than the physicians. The level of physical activity of the HCPs is not associated with their recommendations. To ensure a clear and unique message, educational actions may be undertaken to promote the biopsychosocial model and clarify the guidelines.

Long-Term Outcome After Surgery for a Localized Retroperitoneal Soft Tissue Sarcoma in Elderly Patients: Results from a Retrospective, Single-Center Study.

BACKGROUND: To evaluate short- and long-term results after curative surgery for a retroperitoneal sarcoma (RPS) in elderly patients. METHODS: We retrospectively analyzed data of all patients operated in our single, tertiary care center for a nonmetastatic RPS and identified patients aged 70 years and older. RESULTS: Among 296 patients with an RPS treated between 1994 and 2015, 60 (20%) were aged 70 years and older (median age 74 years; range 70-85). The median tumor size was 24 cm (range 6-46). Forty-six patients (77%) had mass-related symptoms at the time of diagnosis. The most frequent histological subtypes were de-differentiated liposarcoma (53%, n = 32) and well-differentiated liposarcoma (35%, n = 21). Twenty-two patients (37%) had perioperative radiotherapy and/or chemotherapy. Fifty-eight patients (97%) had macroscopically complete resection. The postoperative mortality was 8% and severe morbidity (Dindo/Clavien ≥ 3) was 32%. A reoperation was required for ten patients (17%). After a median follow-up of 20 months (range 1-121), the 5-year overall survival (OS) rate was 90% (95% confidence interval [CI] 79-100%), and median OS was not reached. The cancer-specific death rate was 88%. No prognostic factor for disease-specific survival was detected. The 5-year disease-free survival (DFS) rate was 52% (95% CI 33-84%) and 5-year locoregional recurrence-free survival rate was 52% (95% CI 33-84%). Median DFS was 94 months (95% CI 35-NA). Reoperation after inappropriate surgery and postoperative morbidity were independent predictive factors of locoregional relapse. No predictive factors of distant metastasis were found. CONCLUSIONS: Curative surgery is feasible in selected elderly patients but with higher mortality and morbidity rates than in younger patients. It enables a prolonged survival. Future studies should focus on selection process to minimize postoperative mortality and morbidity.

Prediction of local and metastatic recurrence in solitary fibrous tumor: construction of a risk calculator in a multicenter cohort from the French Sarcoma Group (FSG) database.

BACKGROUND: Solitary fibrous tumors (SFT) are rare unusual ubiquitous soft tissue tumors that are presumed to be of fibroblastic differentiation. At present, the challenge is to establish accurate prognostic factors. PATIENTS AND METHODS: A total of 214 consecutive patients with SFT diagnosed in 24 participating cancer centers were entered into the European database (www.conticabase.org) to perform univariate and multivariate analysis for overall survival (OS), local recurrence incidence (LRI) and metastatic recurrence incidence (MRI) by taking competing risks into account. A prognostic model was constructed for LRI and MRI. Internal and external validations of the prognostic models were carried out. An individual risk calculator was carried out to quantify the risk of both local and metastatic recurrence. RESULTS: We restricted our analysis to 162 patients with local disease. Twenty patients (12.3%) were deceased at the time of analysis and the median OS was not reached. The LRI rates at 10 and 20 years were 19.2% and 38.6%, respectively. The MRI rates at 10 and 20 years were 31.4% and 49.8%, respectively. Multivariate analysis retained age and mitotic count tended to significance for predicting OS. The factors influencing LRI were viscera localization, radiotherapy and age. Mitotic count, tumor localization other than limb and age had independent values for MRI. Three prognostic groups for OS were defined based on the number of unfavorable prognostic factors and calculations were carried out to predict the risk of local and metastatic recurrence for individual patients. CONCLUSION: LRI and MRI rates increased between 10 and 20 years so relapses were delayed, suggesting that long-term monitoring is useful. This study also shows that different prognostic SFT sub-groups could benefit from different therapeutic strategies and that use of a survival calculator could become standard practice in SFTs to individualize treatment based on the clinical situation.

Abdominal desmoplastic small round cell tumor without extraperitoneal metastases: Is there a benefit for HIPEC after macroscopically complete cytoreductive surgery?

BACKGROUND: Desmoplastic Small Round Cell Tumor (DSRCT) is a rare disease affecting predominantly children and young adults and for which the benefit of hyperthermic intraperitoneal chemotherapy (HIPEC) after complete cytoreductive surgery (CCRS) remains unknown. METHODS: To identify patients with DSRCT without extraperitoneal metastases (EPM) who underwent CCRS between 1991 and 2015, a retrospective nation-wide survey was conducted by crossing the prospective and retrospective databases of the French Network for Rare Peritoneal Malignancies, French Reference Network in Sarcoma Pathology, French Sarcoma Clinical Network and French Pediatric Cancer Society. RESULTS: Among the 107 patients with DSRCT, 48 had no EPM and underwent CCRS. The median peritoneal cancer index (PCI) was 9 (range: 2-27). Among these 48 patients, 38 (79%) had pre- and/or postoperative chemotherapy and 23 (48%) postoperative whole abdominopelvic radiotherapy (WAP-RT). Intraperitoneal chemotherapy was administered to 11 patients (23%): two received early postoperative intraperitoneal chemotherapy (EPIC) and nine HIPEC. After a median follow-up of 30 months, the median overall survival (OS) of the entire cohort was 42 months. The 2-y and 5-y OS were 72% and 19%. The 2-y and 5-y disease-free survival (DFS) were 30% and 12%. WAP-RT was the only variable associated with longer peritoneal recurrence-free survival and DFS after CCRS. The influence of HIPEC/EPIC on OS and DFS was not statistically conclusive. CONCLUSION: The benefit of HIPEC is still unknown and should be evaluated in a prospective trial. The value of postoperative WAP-RT seems to be confirmed.

Renal angiomyolipomas: At least two diseases. A series of patients treated at two European institutions.

OBJECTIVE: The aim of this study is to analyze the outcome of renal angiomyolipomas (AML) at two European institutions. METHODS: The data were collected from patients with a primary AML who were treated at Gustave Roussy, Villejuif, France and Fondazione IRCCS Istituto Nazionale dei Tumori in Milan, Italy from 1998 to 2014. The specimens were classified as classic AML (C AML) or epithelioid AML (E AML) based on the percentage of epithelioid cells. RESULTS: There were 40 patients identified for the study (35 C AML, 5 E AML). One patient had an associated tuberous sclerosis complex. Six patients (15%) had bilateral AML. The imaging results were significantly different between C/E AML. E AML was associated with fewer bilateral lesions, more renal vein/vena cava extension, and more poor or non-fatty aspects. Surgery/active surveillance (AS)/chemo radiation were applied for 28/11/1 patients, respectively. The median tumor size was significantly smaller (3.75 cm) in patients receiving AS (median 15 cm when surgically resected). The median patient follow-up was 43 months. The three-year overall survival was significantly better for patients with C AML than E AML (100% versus 50%, p < 0.0001). The univariate analysis identified the OS prognostic factors were E AML histologic subtype (p < 0.001), poor/non fatty features (p = 0.002), and renal vein extension on imaging (p = 0.01). CONCLUSION: AML manifests as at least two different entities with significantly different outcomes. Epithelioid subtype, poor/non-fatty features, and renal vein involvement are all associated with worse survival.

Evaluation of response after pre-operative radiotherapy in soft tissue sarcomas; the European Organisation for Research and Treatment of Cancer-Soft Tissue and Bone Sarcoma Group (EORTC-STBSG) and Imaging Group recommendations for radiological examination and reporting with an emphasis on magnetic resonance imaging.

At present, there is no standardised approach for the radiological evaluation of soft tissue sarcomas following radiotherapy (RT). This manuscript, produced by a European Organisation for Research and Treatment of Cancer-Soft Tissue and Bone Sarcoma Group (EORTC-STBSG) and Imaging Group endorsed task force, aims to propose standardisation of magnetic resonance imaging techniques and interpretation after neoadjuvant RT for routine use and within clinical trials.

Toward a new strategy in desmoid of the breast?

AIM: To report initial results of observation as well as surgery in patients with desmoid tumors (DTs) of the breast, a rare tumor for which data are scarce. PATIENTS AND METHODS: The initial approaches were categorized as either front-line loco-regional treatment [(surgery or radiotherapy group, SRG) n = 20] or initial observation [(no surgery/no radiotherapy group, NSRG) n = 11]. RESULTS: A total of 27 women and 4 men were assessed between 1992 and 2013 and included in this study. Patient characteristics were adequately balanced in the 2 groups. Fifteen patients (48.4%) had a past history of breast surgery in the previous 24 months. The median initial DT size on MRI was 50 mm. The median follow-up was 36 months. In the SRG, 8/20 patients (40%) experienced recurrence. The median time to recurrence was 29 months. During the study period, 6 patients in the SRG (30%) received a mastectomy at the time of diagnosis (n = 3) or at relapse (n = 3), 7 patients (35%) received a thoracic wall resection and 8 patients (40%) received radiotherapy at the time of diagnosis (n = 2) or at recurrence (n = 5). In the NSRG, the median tumor size change was -4 mm (range -13 to +20). Three patients changed treatment strategies during the observation period; one received surgery, and 2 were administered anti-hormonal treatment. CONCLUSIONS: Loco-regional treatments of breast DTs resulted in undesired disfigurement. Front-line observation yielded encouraging results and could enable the identification of patients who require loco-regional treatment. This strategy needs further evaluation.

Is preoperative radiotherapy suitable for all patients with primary soft tissue sarcoma of the limbs?

AIM: To evaluate the indications and results of preoperative radiotherapy (RT) on a series of selected patients treated at our institution with curative intent for a limb sarcoma (STS). PATIENTS AND METHODS: From 05/1993 to 12/2011, 64 STS patients received preoperative RT. RESULTS: RT was delivered as a "limb salvage treatment" prior to surgery for the following reasons: as the preferential induction treatment in 53 patients (83%) or as a second intent (17%) after the failure of neoadjuvant systemic chemotherapy/isolated limb perfusion. Surgery was performed after RT in 54 (84%) patients and final limb salvage was performed in 98%. Musculo-cutaneous flap reconstruction was planned upfront in 44% patients, and 19% had a skin graft. Seven patients (13%) had a postoperative RT boost. Thirteen (20%) patients had grade (G) 3/4 adverse events, one after RT and 12 after surgery. At a median follow-up of 3.5 years, the 3-year actuarial overall survival (OS) and distant relapse (DR) rates were 83% and 31%, respectively. Two patients developed a local relapse and two a local progression (non-operated patients). In the multivariate analysis (MVA), histological subtype (leiomyosarcoma) and grade 3 were predictive of poorer survival. Patients with >3 month delay between the start of RT and surgery at our institution had an increased risk of DR in the MVA. CONCLUSION: Induction RT should be personalised according to histological subtype, tumour site and risks-benefit ratio of preoperative radiotherapy and is best managed by a multidisciplinary surgical and oncology team in a specialist sarcoma centre.

Response to chemotherapy is not related to chromosome instability in synovial sarcoma.

BACKGROUND: Synovial sarcoma (SS) is an aggressive soft-tissue tumor. Despite being considered as a chemosensitive disease, the real impact of perioperative chemotherapy on metastasis-free survival (MFS) is controversial. We have shown that metastatic relapse of SS is strongly associated with genomic complexity. There are no data regarding the potential correlation between genomic complexity and response to chemotherapy. PATIENTS AND METHODS: The study population included 65 SS patients diagnosed between 1991 and 2013 and with available tissue material. Genomic profiling was carried out by using array-CGH. Forty-five SS out of the 65 patients were treated with neoadjuvant anthracycline/ifosfamide-based chemotherapy. Radiological response was assessed according to RECIST criteria. Histological response was defined by the percentage of recognizable tumor cells on the surgical specimen. RESULTS: Genomic complexity was significantly associated with MFS. However, there was no statistically significant association between radiological or histological response and genomic complexity. CONCLUSION: The absence of significant association between response to chemotherapy and genomic complexity suggests that the prognostic value of chromosome instability in SS is independent of response to chemotherapy; mechanisms leading to metastatic relapse of SS are intrinsic to the biology of the tumor and current cytotoxic drugs are only poorly efficient to prevent it.

Retroperitoneal sarcomas: patterns of care at diagnosis, prognostic factors and focus on main histological subtypes: a multicenter analysis of the French Sarcoma Group.

BACKGROUND: Retroperitoneal sarcomas (RPS) are heterogeneous. No previous study has investigated the impact of specialized surgery, evaluated locoregional relapse (LRR), abdominal sarcomatosis and distant metastatic relapse as separate events, or considered histological subtypes separately. This study addresses these specific points in a homogeneous cohort of patients with completely resected primary RPS. PATIENTS AND METHODS: We conducted a retrospective analysis of adult patients diagnosed with a RPS between 1 January 1988 and 31 December 2008 and eventually referred to one of 12 centers of the French Sarcoma Group. All cases were centrally reviewed by an expert pathologist. RESULTS: Five hundred eighty-six patients were included. Median follow-up was 6.5 years [95% confidence interval (CI) 5.9-7.1]. Five hundred thirty-seven patients had localized disease and 389 patients (76%) had macroscopically complete resection of the tumor. In this latter group, the 5-year LRR-free survival rate was 46% [41-52] and the 5-year overall survival (OS) rate was 66% [61-71]. In multivariate analysis, gender, adjacent organ involvement, specialization of the surgeon, piecemeal resection and perioperative radiotherapy were independently associated with LRR. Specialization of the surgeon and piecemeal resection were independently associated with abdominal sarcomatosis whereas histology and adjacent organ involvement were independently associated with distant metastasis. Age, gender, grade, adjacent organ involvement and piecemeal resection were significantly associated with OS. Prognostic factors for LRR and OS were analyzed in well-differentiated and dedifferentiated liposarcomas and leiomyosarcomas. Grade 3 was an independent prognostic factor for OS of dedifferentiated liposarcomas. CONCLUSION: This study underlines the crucial role of pretherapeutic assessment and meticulous histological examination of RPS as well as the need to consider histological subtypes separately. Surgery in a specialized center and avoidance of piecemeal resection stand out as the two most important prognostic factors for RPS and highlight the importance of treating these patients in specialized centers.

Retroperitoneal sarcomas: patterns of care in advanced stages, prognostic factors and focus on main histological subtypes: a multicenter analysis of the French Sarcoma Group.

BACKGROUND: Retroperitoneal sarcomas (RPS) are heterogeneous. Advanced stages include unresectable locoregional (LR) disease, abdominal sarcomatosis and distant metastasis. There is no available report assessing palliative chemotherapy in advanced RPS. This study analyzes management and outcome in a large cohort of patients with advanced RPS, considering main histological subtypes separately. PATIENTS AND METHODS: We conducted a retrospective analysis of adult patients diagnosed with a RPS between 1 January 1988 and 31 December 2008 across 12 centers of the French Sarcoma Group. All cases were centrally reviewed by an expert pathologist. RESULTS: Five-hundred eighty-six patients were included, 299 patients received palliative chemotherapy, with a median of two lines (range 0-8). Fifty patients underwent palliative surgery. Two hundred fifty-five patients (85%) were assessable for response after first line of chemotherapy. Among them, 69 patients (27%) had progressive disease, 145 (57%) had stable disease, 37 (14.5%) had partial response and 4 (1.5%) complete response. Median time from first line of palliative chemotherapy to progression was 5.9 months [4.9-7.3] and median overall survival (OS), 15.8 months [13-18]. In multivariate analysis, prognosis factors independently associated with poor OS were male gender, performance status (PS) >1 and grade >1. There was no difference according to stage of disease. Palliative surgery did not appear to add any survival benefit. CONCLUSION: These results emphasize the scarcity of available options for RPS in the advanced setting and the urgent need to develop new strategies. Patients with good PS should be included in clinical trials and best supportive care should be considered in those with poor PS.

Should adjuvant radiotherapy be administered in addition to front-line aggressive surgery (FAS) in patients with primary retroperitoneal sarcoma?

BACKGROUND: As most patients with retroperitoneal sarcomas (RPS) die of local recurrence, front-line aggressive surgery (FAS) has been developed, and it seems to achieve better local control. The aim of this study was to evaluate conformal postoperative radiotherapy (PORT) in patients who had enlarged surgery. PATIENTS AND METHODS: Between 1994 and 2008, 110 patients with primary RPS mainly operated by FAS were analysed. Sixty-two patients underwent surgery and no PORT (group S), and 48 received surgery and PORT (group S + R). The median age was 52. Most patients had 3D conformal PORT (81%) with a median dose of 50 Gy. RESULTS: Comparing results at 5 years in the S and the S + R group, the cumulative rate of local failure was, respectively, 36% and 22% (NS); relapse-free survival was 47% and 60% (P = 0.02), and overall survival was, respectively, 77% and 71% (NS). CONCLUSION: Even if patients with adjuvant PORT were at higher risk of recurrence, there was a trend for radiotherapy (RT) to decrease the local relapse rate and improve recurrence-free survival. This study confirms that adjuvant conformal RT should be evaluated in a randomized trial, the control arm being FAS. Adjuvant RT in the preoperative setting is being evaluated in an EORTC trial.

The treatment of desmoid tumors: a stepwise clinical approach.

Aggressive fibromatosis (AF) is a monoclonal proliferative disease but does not metastasize and does not dedifferentiate to a high-grade malignancy in case of recurrence. Biopsy is usually necessary to confirm the diagnosis. A hallmark is its apparent unpredictable clinical course producing a large heterogeneity even with an indistinguishable morphology. Additional studies of the molecular determinants of desmoid behavior are needed to guide selection of the various therapeutic modalities. During the last 10 years, the treatment of AF has evolved and the role of routine, aggressive first-line treatment (radiotherapy and surgery) is now debated. If a wait-and-see policy is used at initial presentation, it is observed that >50% of patients will have relatively indolent disease. Aggressive treatments that take their indications from retrospective studies should be re-evaluated in the light of new data. The objective of this article is to propose an algorithm that commences with more conservative approaches before treatments that have associated long-term morbidity, the more aggressive therapies being reserved only for those who really need it.

Clear cell sarcoma (malignant melanoma) of soft parts: a clinicopathologic study of 52 cases.

Clear cell sarcomas are aggressive, rare soft tissue tumors and their classification among melanoma or sarcoma is still undetermined due to their clinical, pathologic, and molecular properties found in both types of tumors. This is a retrospective study of 52 patients with CCS seen between April 1979 and April 2005 in two institutions. The EWS-ATF-1 fusion transcript was studied in 31 patients and an activating mutation of the BRAF or NRAS gene was researched in 22 patients. 30 men and 22 women, with a mean age of 33 were studied. Forty-three tumors (82.69%) were located in the extremities, specially the foot (19 tumors). Median initial tumor size was 4.8 cm (1 to 15 cm). Necrosis involving more than 50% of the tumor cells was found in 14 cases (26.92%). High mitotic rate (>10) was found in 25 cases (48.07%). The EWS/ATF-1 translocation was found in 28 (53.84%) of 31 patients studied, and mutation of BRAF or NRAS was found in only 2 of 22 patients analyzed cases (3.84%). Among the tumor-associated parameters, only tumor size (>4 cm) emerged as a significant prognostic factor. Forty-nine patients had a localized disease at diagnosis (94.23%) and underwent surgical resection immediately (90%) or after neoadjuvant chemotherapy (CT) (10%). Various CT regimens were used in 37 patients (71.15%) with no significant efficacy. The 5- and 10-year OS rates were 59% and 41%, respectively. Tumor size was the only emerging prognosis factor in our series. Complete surgical resection remains the optimal treatment for this aggressive chemoresistant tumor.

Characterization of a medium by estimating the constituent components of its coherency matrix in polarization optics.

In this work, an alternative route to analyze a set of coherency matrices associated to a medium is addressed by means of the Independent Component Analysis (ICA) technique. We highlight the possibility of extracting an underlying structure of the medium in relation to a model of constituent components. The medium is considered as a mixture of unknown constituent components weighted by unknown but statistically independent random coefficients of thickness. The ICA technique can determine the number of components necessary to characterize a set of sample of the medium. An estimate of the value of these components and their respective weights is also determined. Analysis of random matrices generated by multiplying random diattenuators and depolarizers is presented to illustrate the proposed approach and demonstrate its capabilities.

[Intensity modulated radiotherapy as adjuvant post-operative treatment for retroperitoneal sarcoma: acute toxicity]. / Radiothérapie avec modulation d'intensité dans le traitement postopératoire des sarcomes rétropéritonéaux: profil de toxicité aiguë.

PURPOSE: To assess the acute toxicity of intensity modulated radiotherapy as post-operative adjuvant treatment for retroperitoneal sarcoma. PATIENTS AND METHODS: Patients who received adjuvant intensity modulated radiotherapy from January 2009 to September 2010 were retrospectively reviewed. RESULTS: Fourteen patients entered the study (seven primary tumours and seven relapses). All tumours were liposarcoma and had macroscopically complete resection, epiploplasty was systematically realized. Median tumour size was 21 cm (range: 15-45), median planning target volume was 580 cm(3) (range: 329-1172) and median prescribed dose was 50.4 Gy (range: 45-54). Median follow-up was 11.5 months (range: 2-21.4). Acute toxicity was mild: acute digestive toxicity grade 1-2 occurred in 12/14 patients (86%). However, there was no weight loss of more than 5% during radiotherapy and no treatment interruption was required. Two months after completion of radiotherapy, digestive toxicity grade 1 remained present in 1/14 patients (7%). One case of grade 3 toxicity occurred during follow-up (transient abdominal pain). Three relapses occurred: two were outside treaded volume and one was both in and outside treated volume. CONCLUSIONS: Intensity modulated radiotherapy in the postoperative setting of retroperitoneal sarcoma provides low acute toxicity. Longer follow-up is needed to assess late toxicity, especially for bowel, kidney and radio-induced malignancies.

APCI/APPI for synthetic polymer analysis.

Modern mass spectrometry of synthetic polymers involves soft ionization techniques. Whereas matrix-assisted laser desorption/ionization (MALDI) and electrospray (ESI) are employed routinely, atmospheric pressure chemical ionization (APCI) and more recently atmospheric pressure photoionization (APPI) are used to a lesser extent. However, these latter ionization methods coupled to liquid-phase separation techniques create new opportunities for the characterization of polymers, especially for low molecular weight compounds or for the polymers that are poorly ionizable by the usual methods. After a part devoted to the description of classical MS methods employed for polymer analysis (MALDI, ESI, and their use with chromatography), APCI and APPI techniques will be described, discussed, and selected examples will present the interest of these ionization sources (or interfaces for LC/MS) in the field of polymer analysis.