Utilization of the internal mammary perforators as the recipient vessels for microsurgical breast reconstruction: A systematic review and meta-analysis of the literature.

BACKGROUND: The selection of reliable recipient vessels is essential for successful free tissue transfer. The use of internal mammary intercostal perforators (IMAPs), instead of the internal mammary vessels as the recipient vessels, has been described in breast reconstruction. Debates exist regarding the reliability of these perforators as recipient vessels because of their variability in location and caliber. The aim of this paper was to conduct a systematic literature review and meta-analysis to determine the reliability of the IMAPs as recipient vessels. METHODS: A systematic literature review was performed on the "PubMed," "Medline," "Ovid," and "Cochrane library" databases for articles published from January 1990 to March 2021. Exclusion criteria were non-English studies, reports with case number less than 5, cadaveric or animal studies, and studies with incomplete postoperative outcomes. The reliability of using IMAPs for breast reconstruction was determined by assessing the reported rates of partial or complete flap failure and other complications (fat necrosis, skin necrosis, and requirement for revision surgery). RESULTS: Three hundred and sixteen cases in 13 studies were included for further analysis with more than 85% of the IMAPs suitable for anastomosis being located in the second and third intercostal spaces. Partial or total flap failure was reported in three of 316 patients (0.95%). The rate of other complications such as fat necrosis, skin necrosis, and requirement for revision surgery were all less than 5%. CONCLUSION: With deliberate preoperative planning, delicate perioperative manipulation, and meticulous microvascular anastomosis, the internal mammary perforators can be used as reliable recipient vessels in microvascular breast reconstruction.

The impact of post-mastectomy radiation timing on overall outcomes of autologous free-flap breast reconstruction.

BACKGROUND: The optimal timing of post-mastectomy radiation therapy (PMRT) in autologous breast reconstruction is controversial. Our study compares overall reconstructive outcomes in patients who received post-mastectomy radiation therapy either before or after the autologous flap. METHODS: A single-center retrospective review was performed for patients who underwent free flap breast reconstruction and post-mastectomy radiation from January 2004 through January 2021. Demographic, intraoperative, and post-operative variables were recorded. RESULTS: A total of 452 free flaps were identified, and 82 underwent PMRT. 59.8% were radiated with an expander prior to free flap surgery (PreFlap), and 40.2% flaps underwent PMRT (PostFlap). PostFlap patients were significantly younger (43.0 vs. 47.9 years, p = .016). There were no significant differences in free flap outcomes between the two cohorts including thrombosis, venous congestion, flap loss, takebacks, fat necrosis, seroma, or infection. Mastectomy skin flap necrosis was significantly higher in the PostFlap cohort (9.1% vs. 0%, p = .032), but nipple necrosis rates did not differ. There were no significant differences in number or need for revision surgeries, fat necrosis, or fat grafting between groups. However, there were significantly more total reconstructive complications, including infection and wound breakdown, experienced by the PreFlap cohort (46.9% vs. 24.2%, p = .038). CONCLUSIONS: Timing of PMRT did not impact free flap outcomes, but those who had the expander radiated experienced significantly more complications overall. For the 34.7% of patients in the preFlap group who planned for autologous reconstruction form initial consultation, radiation after the flap may have improved their overall outcomes. As added complications cause delays in cancer therapy and final reconstruction, our results suggest that PMRT of the flap when possible may improve the overall experience for breast cancer patients.

Surgical management of breast fat necrosis: Multi-institutional data analysis of early outcomes and risk factors for complications.

BACKGROUND: Breast fat necrosis (BFN) is a non-cancerous condition affecting the adipose tissue. Despite incidence rates of up to 25% after breast surgery, little is known about risk factors and postoperative outcomes following the surgical treatment of BFN. METHODS: The National Surgical Quality Improvement Program of the American College of Surgeons (2008-2021) was queried to identify female patients diagnosed with and surgically treated for BFN. Outcomes of interest included 30-day surgical and medical complications, reoperation, and readmission. We performed confounder-adjusted multivariable analyses to determine risk factors. RESULTS: The study population included 1179 female patients (mean age: 55.8 ± 13.8 years), of whom 96% (n = 1130) underwent direct excision and 4.2% (n = 49) received debridement of necrotic tissue. The majority of cases were operated on by general surgeons (n = 867; 74%) in the outpatient setting (n = 1107; 94%). Overall, 74 patients (6.3%) experienced postoperative adverse events, most of which were surgical complications (n = 43; 3.7%). Twenty-one (1.8%) women had to return to operating room, while readmission was reported in 18 (1.5%) cases. Adverse events were significantly more likely to occur in patients with chronic heart failure (p = 0.002) and higher wound classes (p = 0.033). CONCLUSION: Complication rates following the surgical management of BFN were found to be relatively high and seen to correlate with the setting. We identified chronic heart failure and wound contamination as risk factors for complication occurrence. These evidence-based insights may sensitize surgeons to critically balance patients' eligibility for BFN surgery and refine perioperative algorithms.

Abandoning the SIEA Flap for the Dual-Plane DIEP Reduces Fat Necrosis and Flap Failure.

BACKGROUND: Despite its limitations in abdominally based breast reconstruction, using the superficial inferior epigastric artery (SIEA) flap or system can be advantageous in specific clinical scenarios. To optimize outcomes in these cases, the authors performed a retrospective review of their flap series to advocate a new algorithm to use the superficial system. METHODS: A retrospective analysis was performed on 1700 consecutive free abdominal flaps for the presence of a dominant superficial system or poor deep inferior epigastric artery perforators (DIEP) on clinical examination or angiography. In this setting, the authors analyzed the primary outcome measures of fat necrosis and flap failure with use of the superficial system alone versus a "dual-plane DIEP," where there was an intraflap anastomosis performed between the DIEP pedicle and SIEA pedicle. A multivariable analysis was performed with 21 other potentially confounding variables and compared with outcomes with traditionally perfused DIEP flaps. RESULTS: Fat necrosis was present in 13% of 506 DIEP flaps, 34.1% of 41 SIEA system flaps, and 2.7% of 37 dual-plane DIEP flaps. Superficial system-only flaps were independent predictors of fat necrosis (OR, 6.55; P < 0.001) and flap failure (OR, 9.82; P = 0.002) compared with dual-plane DIEP flaps when used for the same indications. CONCLUSION: In settings of superficial dominance or need to augment perfusion to lateral zones in abdominal free flaps, performing a dual-plane DIEP flap instead of using the superficial system vasculature alone with an SIEA flap can decrease the odds of fat necrosis and flap failure to equal that of a standard DIEP flap. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

Oncologic Safety in Autologous Fat Grafting After Breast Conservation Therapy: A Systematic Review and Meta-analysis of the Literature.

BACKGROUND: Autologous fat grafting (AFG) is often used to reconstruct defects after breast conservation therapy (BCT). However, concerns exist about the possibility of AFG-related recurrence or metastasis. This study aims to evaluate the literature to evaluate oncologic outcomes in patients undergoing AFG at the time of BCT. METHODS: A systematic review of articles related to AFG based reconstruction at the time of BCT from 1970 to 2021 was performed via PubMed. Patients were grouped based on the presence or lack of AFG usage at the time of BCT, and oncologic outcomes and complications were compared. RESULTS: Of the 146 articles identified, 15 were included. Nine hundred patients underwent BCT alone and 1063 patients underwent BCT with AFG patients. Similar average follow-up time was observed between the groups, 58.7 months (BCT only) and 55.2 months (BCT with AFG). On pooled analysis, no difference was identified in local recurrence 4.8% (43 patients) of the BCT group and 3% (32 patients) in the AFG group (P = 0.8), metastasis 4.8% (43 patients) of the BCT group and 6.9% (73 patients) in the AFG group (P = 0.3), or fat necrosis (P = 0.44). Meta-analysis additionally did not identify any statistically significant odds ratios between the BCT only group and BCT with AFG group when evaluated for total recurrence, local recurrence, metastasis or fat necrosis. CONCLUSIONS: The results show no significant difference in cancer recurrence or metastasis in the BCT only group versus BCT and AFG, showing that fat grafting has safe outcomes.

The treatment of symptomatic fat necrosis: A review and introduction of a new treatment algorithm.

OBJECTIVE: Fat necrosis (FN) is a well-known complication in plastic surgery. Excision of symptomatic FN has been the gold standard, but it often results in contour irregularities that require subsequent treatment. Different alternative surgical and nonsurgical management strategies have been described; however, there are currently no guidelines. This literature review aims to provide an overview of available treatment options and current management standards to support clinical decision making. METHOD: A literature search in the databases PubMed, Embase (via Ovid), and Web Of Science was carried out to identify eligible articles. The search strategy included combinations of the following terms: "Fat necrosis "AND (treatment OR management OR therapy). Six articles discussing or reporting management strategies of FN in a plastic surgery context were included. RESULTS: A variety of techniques were used to manage symptomatic FN. Asymptomatic or small lesions can be treated conservatively. Oil cyst and moderately sized areas of symptomatic FN can effectively be treated by aspiration, ultrasound-assisted liposuction, or needle aeration. Calcified and large areas of FN require excision and debridement of necrotic fat tissue CONCLUSION: At present, there is no consensus on the management of symptomatic FN. The authors propose a new classification system to aid the guidance of management of symptomatic FN.

A Prospective, Randomized Comparison of Clinical Outcomes with Different Processing Techniques in Autologous Fat Grafting.

BACKGROUND: Autologous fat grafting is a useful tool in breast reconstruction. The authors have previously demonstrated a difference in the rate of processing adipose grafts in a randomized time and motion clinical trial. The purpose of this study was to compare clinical outcomes in commonly used grafting systems. METHODS: Three methods to prepare adipose grafts were compared: a passive washing filtration system (Puregraft system), an active washing filtration system (Revolve system), and centrifugation (Coleman technique). Postoperative complications, rates of fat necrosis, revision procedures, and additional imaging were recorded. RESULTS: Forty-six patients were included in the prospective, randomized study (15 active filtration, 15 passive filtration, and 16 centrifugation). Their mean age was 54 years and mean body mass index was 28.6 kg/m 2 . The mean length of follow-up was 16.9 ± 4 months. The overall complication rate was 12.1 percent. The probability of fat necrosis was no different between the groups (active filtration, 15 percent versus passive filtration, 14.3 percent] versus centrifugation, 8 percent; p = 0.72). Fat necrosis was highest in patients with breast conservation before grafting (60 percent; p = 0.011). There was no significant difference in contour irregularity (active filtration, 40 percent versus passive filtration, 38 percent versus centrifugation, 36 percent; p = 0.96) or additional grafting (active filtration, 40 percent versus passive filtration, 24 percent versus centrifugation, 32 percent; p = 0.34). CONCLUSIONS: This is the first prospective, randomized study to compare clinical outcomes of adipose graft preparation. There was no significant difference in early complications, fat necrosis, or rates of additional grafting among the study groups. There was significantly higher risk of fat necrosis in patients with previous breast conservation treatment regardless of processing technique. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, II.

Large-Volume Fat Grafting: Identifying Risk Factors for Fat Necrosis.

BACKGROUND: Fat necrosis is a well-recognized complication following autologous fat grafting. The purpose of this study was to evaluate the incidence of fat necrosis after large-volume fat grafting and identify risk factors for fat necrosis. METHODS: A retrospective review was performed on 83 consecutive patients who underwent large-volume fat grafting (>100 cc) to the breast performed by the senior author (L.P.B.) between September of 2011 and May of 2016. Fat necrosis was defined as palpable nodules, or nodules seen on imaging. RESULTS: A total of 148 breasts underwent 170 autologous fat transplantations. Indications included the following: 72 reconstructions after surgical therapy and 98 cosmetic augmentations. Mean age was 48 years, median graft volume was 300 cc, and median length of follow-up 423 days. Overall incidence of necrosis was 32.9 percent, with 47.8 percent in previously irradiated patients. Increased incidence of necrosis was associated with increasing fat graft volumes (OR, 1.002; p = 0.032), increasing body mass index (OR, 1.13; p = 0.04), and simultaneous implant exchange with fat ( p = 0.003). Fat grafting volumes greater than 450 cc in a single breast were also associated with an increase in fat necrosis ( p = 0.04). Within a group of six patients who had bilateral fat grafting with unilateral radiation therapy, there was a significant increase in necrosis on the irradiated side ( p = 0.015). In a cohort of non-BRAVA patients, reconstruction (compared to augmentation) was associated with fat necrosis ( p = 0.039). CONCLUSIONS: Increased rates of fat necrosis were associated with volumes greater than 450 cc, patients undergoing concurrent implant exchange with fat grafting, and fat grafting after a history of lumpectomy or mastectomy without preexpansion. In addition, radiation therapy may be associated with a higher rate of complications. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, III.

"Immediate versus delayed autologous breast reconstruction in patients undergoing post-mastectomy radiation therapy: A paradigm shift".

BACKGROUND: While negative impacts of radiation on breast reconstruction have been well accepted, timing of autologous breast reconstruction in the setting of postmastectomy radiation therapy (PMRT) is still evolving. This study aims to address the dilemma of breast reconstruction timing in patients receiving PMRT. METHODS: A retrospective chart review was performed evaluating patients who underwent PMRT and autologous breast reconstruction. Postoperative complication and revision rates were compared. RESULTS: Thirty-six immediate (immediate breast reconstruction [IBR]) and 89 delayed reconstructions (delayed breast reconstruction [DBR]) were included with comparable patient characteristics between groups. Overall complication rates were not significantly different, or when separately assessing for surgical site infections, wound dehiscence, fat necrosis, or substantial volume loss. No free flaps were lost in either group. Revision rates were significantly lower in the IBR group (p = 0.02). DBR resulted in appreciably larger volumes of fat grafting to the therapeutically reconstructed breast (p = 0.01) and more contralateral mastopexies (p = 0.02). No significant difference was observed in fat necrosis excision, breast reduction, or need for secondary flap reconstruction or prosthetic use for volume loss. CONCLUSIONS: IBR in the setting of PMRT does not result in higher rates of complications and requires fewer overall revisions, making it a compelling option for patients undergoing PMRT.

Treating Pain and Fat Necrosis after Breast Cancer Surgery with Fat Grafting: Is one Session Enough?

BACKGROUND: Chronic pain after breast cancer surgery is affecting up to 60% of patients, causing significant morbidity to patients. Lately, fat grafting has been applied as a therapy for chronic neuropathic pain. METHODS: We report a series of eighteen patients, who were treated for pain after breast cancer surgery. Twelve patients had a breast conserving therapy, two a mastectomy and four an autologous flap-based reconstruction. While most presented with neuropathic pain, six patients had fat necrosis in their history. Most patients presented with severe pain (77%) and were treated with fat grafting sessions, performed by water-assisted liposuction. RESULTS: All patients responded to the interventions; the median number of fat grafting sessions was 2, the median duration of the interventions was 4 months, and the median follow-up period was 56.5 months. The median pain prior to the fat grafting procedure had an intensity of 8 (range 7-9) numeric rating scale points; after the first intervention, this was reduced to 4 (range 2.3-5.8); and after the second intervention, it was down to 2 (range 0.8-3.3). Patients with pain intensities of 4-5 had a good chance of achieving analgesia after one session. CONCLUSIONS: Fat grafting could be a new treatment modality for symptomatic fat necrosis: complete or partial suction of the necrosis and/or fat grafting around the necrosis to reduce inflammation and pain. Fat grafting proved a valuable tool, reducing pain or even achieving analgesia after breast cancer surgery presenting with a highly favorable risk-benefit ratio. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these evidence-based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

The correlation of flap blood glucose with fat necrosis of free abdominal flap for unilateral breast reconstruction.

BACKGROUND: Flap blood glucose (FBG) measurement is proposed as a monitoring technique. A cause of long-lasting fever could be derived from fat necrosis. If the findings of low FBG correlated with fat necrosis, it could predict the poor cosmetic result and a source of fever. However, this correlation remained unsolved. The purpose of this study was to clarify this correlation in breast reconstruction. METHODS: In the 180 unilateral breast cancer patients (mean age = 49.8 years) performed free abdominal flap, we retrospectively compared the group where fat necrosis occurred with the group where it did not occur (45 patients with fat necrosis vs. 135 patients without). We compared the average of FBG in each postoperative day. RESULTS: The average FBG was significantly lower in patients with fat necrosis in the second postoperative day (115.3 ± 27.3 vs. 126.3 ± 13.7 mg/dl, p = .026) and the third postoperative day (111.1 ± 22.1 vs. 118.8 ± 13.8 mg/dl, p = .036). Mean BMI and inserted total flap weight were significantly higher in patients with the fat necrosis group (24.8 vs. 22.9 kg/m2 , p = .005) (617 vs. 478 g, p = .006). The multivariate analysis revealed early FBG (OR = 0.96, p = .0002) and laterality (right side) (OR = 0.46, p = .043) were independently significant predictors. There were no significant between-group differences regarding other factors (age, systemic blood glucose, comorbidities and operative details). CONCLUSIONS: The possibility of fat necrosis was high for patients with low FBG in the early postoperative day.

Effects of Comorbidities on the Inferior Pedicle Reduction Mammaplasty: A Statistical Analysis.

BACKGROUND: Multiple studies have analyzed the impact of comorbidities on breast reduction surgery with mixed results. The purpose of this investigation was to perform a statistical analysis of all complications by a single surgeon, using a single technique for breast reduction. METHODS: Records of patients undergoing breast reduction from 1984 to 2019 with an inferior pedicle were reviewed. Comorbidities analyzed included hypertension, diabetes, nicotine use, weight of breast tissue resected, pedicle length, and basal metabolic index. The literature on the effects of comorbidities on outcomes for breast reconstruction was also reviewed. RESULTS: Although increasing body mass index significantly increased the rate of fat necrosis, it did not impact those patients requiring reoperation for this complication. Body mass index greater than 35 kg/m 2 , weight of tissue resection greater than 1000 g, and nipple-to-inframammary fold distance greater than 20 cm all increased the odds ratio of having a breast with some fat necrosis. Increasing body mass index increased the risk of wound healing problems (both major and minor), but not for patients requiring reoperation. Body mass index greater than 35 kg/m 2 , breast tissue resection greater than 1000 g, and nipple-to-inframammary fold distance greater than 20 cm only minimally increased the odds ratio for a major wound complication. CONCLUSIONS: Patients with increased body mass index are at greater risk for fat necrosis and wound healing complications. However, these usually can be managed conservatively in patients undergoing inferior pedicle breast reduction. Patients do not require free nipple grafting. The use of nicotine or the presence of diabetes or hypertension does not impact outcome. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, III.

A new indication and surgical procedure to reduce fat necrosis after breast-conserving surgery using an inframammary adipofascial flap.

BACKGROUND: There is little information on the risk factors for fat necrosis after breast-conserving surgery using an inframammary adipofascial flap (IAF). METHODS: We conducted a retrospective cohort study from a single institution evaluating the risk factors for fat necrosis after breast-conserving surgery using an IAF (n = 41) performed from 2005 to 2020 for newly diagnosed stage 0-2 breast cancer or phyllodes tumor. RESULTS: Age (≥50 years of age vs. <50 years of age), mammographic density (fatty vs. other) and operation period (before vs. after revision of surgical procedure and patient indication) were significantly associated with fat necrosis (p = 0.006, p = 0.04 and p = 0.02, respectively). CONCLUSION: Our study suggested that the use of an IAF with crescent dermis and selection of appropriate cases for IAF after breast-conserving surgery may be useful for the purpose of reducing fat necrosis. Further study is needed.

The Impact of Indocyanine Green Angiography on Fat Necrosis in Deep Inferior Epigastric Perforator Flap Breast Reconstruction.

BACKGROUND: The deep inferior epigastric perforator flap (DIEP) is a widely known reliable option for autologous breast reconstruction. One common complication of DIEP procedures is fat necrosis. Consequences of fat necrosis include wound healing complications, pain, infection, and the psychological distress of possible cancerous recurrence. Clinical judgment alone is an imperfect method to detect at-risk segments of adipose tissue. Objective methods to assess perfusion may improve fat necrosis complication rates, reducing additional surgeries to exclude cancer and improve cosmesis for patients. METHODS: The authors performed a retrospective review of patients who underwent analysis of DIEP flap vascularity with or without intraoperative indocyanine green angiography (ICGA). Flap perfusion was assessed using intravenous ICGA and was quantified with both relative and absolute value units of fluorescence. Tissue with observed values less than 25% to 30% relative value units was resected. Postoperative outcomes and fat necrosis incidence were collected. RESULTS: Three hundred fifty-five DIEP flaps were included in the study, 187 (52.7%) of which were assessed intraoperatively with ICGA. Thirty-nine patients (10.9%) experienced operable fat necrosis. No statistically significant difference in incidence of postoperative fat necrosis was found between the 2 groups (P = 0.732). However, a statistically significant relationship was found between fat necrosis incidence and body mass index as both a continuum (P = 0.001) and when categorized as greater than 35 (P = 0.038). CONCLUSIONS: Although ICGA is useful for a variety of plastic surgery procedures, our retrospective review did not show a reduction in operable fat necrosis when using this technology.

Right Epipericardial Fat Necrosis After Thymectomy.

A 62-year-old male patient underwent median sternotomy and thymectomy for thymoma (World Health Organization classification type B1+B3, Masaoka classification stage II). A 10-month follow-up postoperative computed tomography showed a 22-mm nodule in the anterior mediastinal lipid tissue just above the right diaphragm. The patient was followed for 8 years, and the nodule's capsule eventually became calcified. Considering the possibility of postoperative recurrence of thymoma, we excised the nodule. The pathologic diagnosis was epipericardial fat necrosis. In some cases, fat necrosis is difficult to distinguish from malignancy by imaging only; surgical resection has diagnostic significance and should be considered.

The Influence of Closing the Abdominal Donor-Site Superficial Fascial System in Deep Inferior Epigastric Perforator Flap Breast Reconstruction.

BACKGROUND: The superficial fascial system is routinely closed to alleviate tension at the abdominal donor site after harvest of the deep inferior epigastric artery perforator flap (DIEP) for breast reconstruction. This is thought to decrease rates of wound dehiscence and improve contour postoperatively. There has been no comparative analysis on closure of the superficial fascial system and its effect on donor-site outcomes. METHODS: The authors retrospectively evaluated outcomes of DIEP flap breast reconstructions performed between 2017 and 2019. After May of 2018, the surgeons collectively agreed to stop closure of the superficial fascial system. All subsequent patients underwent closure of rectus abdominis fascia followed by skin closure. Patient demographic data and abdominal donor-site comorbidities were recorded between the superficial fascial system closure and no-superficial fascial system closure groups. Representative photographs of patients from the two groups were blindly assessed for scar appearance and contour using previously published grading scales. The results were compared. RESULTS: DIEP flap breast reconstruction was performed in 103 consecutive women. Among patients with abdominal donor-site reconstruction, 66 had superficial fascial system closure and 37 did not. There was not a significant difference in fat necrosis or wound dehiscence between the two groups (p = 0.29 and p = 0.39, respectively). Postoperative abdominal scar and contour were evaluated by 10 independent raters and showed no significant difference between the two groups. CONCLUSION: Omission of superficial fascial system closure resulted in no difference in wound dehiscence or fat necrosis rates and aesthetic appearance of the abdominal scar and contour. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

[Diagnosis and management of fat necrosis after autologous fat transplantation of breast].

OBJECTIVE: To review the diagnosis and management of fat necrosis after autologous fat transplantation of breast. METHODS: Based on the latest related literature, the pathology, clinical and radiographic examinations, influence factors, as well as the management of fat necrosis after autologous fat transplantation for breast augmentation and reconstruction were summarized. RESULTS: Fat necrosis after breast autologous fat transplantation is histologically manifested as hyaline degeneration, fibrosis, and calcification. The diagnosis of fat necrosis includes clinical examination, imaging examination (ultrasound, mammography, and MRI), and biopsy. The occurrence of fat necrosis is closely related to patient's own reason and fat transplantation technology. Optimizing the process of fat acquisition, purification, and transplantation can reduce the occurrence of fat necrosis. Intervention or not after fat necrosis depends on the nature of the nodules. According to the nature of the the nodules, various methods such as simple aspiration, vibration amplification of sound energy at resonance liposuction, or direct excision can be selected. CONCLUSION: Fat necrosis after autologous fat transplantation of breast are difficult to control. How to process fat to minimize the injury and maximize the activity of grafted fat needs further researches.

Fat Necrosis Mimicking Renal Cell Carcinoma Recurrence Following Cryotherapy, Partial Nephrectomy, and Nephrectomy.

OBJECTIVE: To present our experience with three patients surgically treated for suspected recurrent renal cell carcinoma whose final pathology was consistent with tumefactive fat necrosis. METHODS: Three patients underwent definitive therapy for biopsy proven renal cell carcinoma (cryoablation, partial nephrectomy, and nephrectomy) and later demonstrated evidence of recurrent renal cell carcinoma on follow up imaging. All three patients underwent surgical resection of the suspected recurrences with final pathology consistent with tumefactive fat necrosis. RESULTS: The three patients were 60, 74, and 39-years old, respectively. The previous definitive therapies for renal cell carcinoma were percutaneous ablation, RAPN, and nephrectomy. Each patient had previous surgical pathology that confirmed prior renal cell carcinoma. Signs of recurrence on diagnostic imaging occurred 2 years, 23 months, and 8 months post-definitive therapy. CONCLUSION: In patients with a history of renal cell carcinoma, consideration of fat necrosis should be taken into account upon seeing imaging concerning for tumor recurrence. Continued analysis of cases with such a diagnosis will be beneficial in recognizing this possibility to avoid unnecessary surgery or therapy when possible.