Radiation necrosis or tumor progression? A review of the radiographic modalities used in the diagnosis of cerebral radiation necrosis.

PURPOSE: Cerebral radiation necrosis is a complication of radiation therapy that can be seen months to years following radiation treatment. Differentiating radiation necrosis from tumor progression on standard magnetic resonance imaging (MRI) is often difficult and advanced imaging techniques may be needed to make an accurate diagnosis. The purpose of this article is to review the imaging modalities used in differentiating radiation necrosis from tumor progression following radiation therapy for brain metastases. METHODS: We performed a review of the literature addressing the radiographic modalities used in the diagnosis of radiation necrosis. RESULTS: Differentiating radiation necrosis from tumor progression remains a diagnostic challenge and advanced imaging modalities are often required to make a definitive diagnosis. If diagnostic uncertainty remains following conventional imaging, a multi-modality diagnostic approach with perfusion MRI, magnetic resonance spectroscopy (MRS), positron emission tomography (PET), single photon emission spectroscopy (SPECT), and radiomics may be used to improve diagnosis. CONCLUSION: Several imaging modalities exist to aid in the diagnosis of radiation necrosis. Future studies developing advanced imaging techniques are needed.

18F-fluciclovine PET/CT to distinguish radiation necrosis from tumor progression for brain metastases treated with radiosurgery: results of a prospective pilot study.

PURPOSE: Distinguishing radiation necrosis from tumor progression among patients with brain metastases previously treated with stereotactic radiosurgery represents a common diagnostic challenge. We performed a prospective pilot study to determine whether PET/CT with 18F-fluciclovine, a widely available amino acid PET radiotracer, repurposed intracranially, can accurately diagnose equivocal lesions. METHODS: Adults with brain metastases previously treated with radiosurgery presenting with a follow-up tumor-protocol MRI brain equivocal for radiation necrosis versus tumor progression underwent an 18F-fluciclovine PET/CT of the brain within 30 days. The reference standard for final diagnosis consisted of clinical follow-up until multidisciplinary consensus or tissue confirmation. RESULTS: Of 16 patients imaged from 7/2019 to 11/2020, 15 subjects were evaluable with 20 lesions (radiation necrosis, n = 16; tumor progression, n = 4). Higher SUVmax statistically significantly predicted tumor progression (AUC = 0.875; p = 0.011). Lesion SUVmean (AUC = 0.875; p = 0.018), SUVpeak (AUC = 0.813; p = 0.007), and SUVpeak-to-normal-brain (AUC = 0.859; p = 0.002) also predicted tumor progression, whereas SUVmax-to-normal-brain (p = 0.1) and SUVmean-to-normal-brain (p = 0.5) did not. Qualitative visual scores were significant predictors for readers 1 (AUC = 0.750; p < 0.001) and 3 (AUC = 0.781; p = 0.045), but not for reader 2 (p = 0.3). Visual interpretations were significant predictors for reader 1 (AUC = 0.898; p = 0.012) but not for reader 2 (p = 0.3) or 3 (p = 0.2). CONCLUSIONS: In this prospective pilot study of patients with brain metastases previously treated with radiosurgery presenting with a contemporary MRI brain with a lesion equivocal for radiation necrosis versus tumor progression, 18F-fluciclovine PET/CT repurposed intracranially demonstrated encouraging diagnostic accuracy, supporting the pursuit of larger clinical trials which will be necessary to establish diagnostic criteria and performance.

Identifying Brigham and Women's Hospital stage T2a cutaneous squamous cell carcinomas at risk of poor outcomes.

BACKGROUND: Although most of the poor outcomes with cutaneous squamous cell carcinoma (CSCC) occur in high-stage tumors, 26% of nodal metastases and 8% of disease-specific deaths develop in Brigham and Women's Hospital (BWH) T2a tumors. OBJECTIVE: To determine risk factors associated with poor outcomes (nodal metastasis, distant metastases, and disease-specific deaths) in BWH T2a CSCC. METHODS: A 17-year retrospective multi-institutional cohort study of primary CSCC BWH T2a tumors. A predictive model based on tumor characteristics was developed to identify those at higher risk of poor outcomes. RESULTS: Presence of 1 major criterion (primary tumor diameter ≥40 mm, invasion depth beyond subcutaneous fat, poor differentiation, or large-caliber perineural invasion) and ≥ 1 minor criterion (invasion depth in subcutaneous fat, moderate differentiation, small-caliber perineural invasion, or lymphovascular invasion) was most predictive of developing poor outcomes (area under the curve, 0.53; C-statistic, 0.60). This model has a sensitivity of 7.7%, specificity of 97.4%, and a positive and negative predictive value of 33.3% and 86.1%, respectively. The 5-year cumulative incidence of poor outcomes in these tumors is 8.0% (95% CI, 5.1-13.7) compared to 2.8% (95% CI, 1.9-4.1) in other T2a tumors (sub-hazard ratio, 3.0; 95% CI, 1.5-5.8). LIMITATIONS: Multi-institutional cohort study was not externally validated. CONCLUSIONS: BWH T2a-high CSCCs have an 8% chance of developing poor outcomes.

Higher metastasis and death rates in cutaneous squamous cell carcinomas with lymphovascular invasion.

BACKGROUND: Lymphovascular invasion (LVI) is an aggressive histologic finding but is excluded from current staging systems due to its lack of demonstrated independent prognostic significance. OBJECTIVE: To evaluate the impact of LVI on cutaneous squamous cell carcinoma tumor outcomes. METHODS: In total, 10,707 cutaneous squamous cell carcinoma tumors from a 20-year, retrospective, multicenter cohort were stratified by the presence (LVI+) or absence (LVI-) of LVI. Outcomes (local recurrence, in-transit metastasis, nodal metastasis, disease-specific death) were compared based on low (Brigham and Women's Hospital [BWH] stage T1/T2a) and high (BWH T2b/T3) tumor stages. RESULTS: Of the 10,707 tumors, 78 had LVI. The analysis of low-stage BWH tumors showed the LVI+ group had a significantly higher 5-year cumulative incidence of local recurrence (LVI+: 12.3%; LVI-: 1.1%; P < .01), metastasis (LVI+: 4.2%; LVI-: 0.4%; P < .01), and disease-specific death (LVI+: 16.2%; LVI-: 0.4%; P < .01). The analysis of BWH high-stage tumors showed the LVI+ group maintained a higher 5-year cumulative incidence of metastasis (LVI+: 28.5%; LVI-: 16.8%; P = .06) and disease-specific death (LVI+: 25.3%; LVI-: 13.9%; P = .03), however, there was no difference in local recurrence (LVI+: 16.3%; LVI-: 15.8%; P = .11). LIMITATIONS: Retrospective study design. CONCLUSION: LVI+ cutaneous squamous cell carcinomas have higher rates of metastasis and death at 5 years. Future staging systems should consider incorporating LVI.

Immune status does not independently influence cutaneous squamous cell carcinoma metastasis and death when stratified by tumor stage: A dual-center retrospective cohort analysis of primary N0 disease.

BACKGROUND: Although immunocompromised patients have a higher risk of developing cutaneous squamous cell carcinomas, it is unknown whether immune status is an independent risk factor for poor outcomes. OBJECTIVE: To compare cutaneous squamous cell carcinoma outcomes in immunocompromised and immunocompetent patients when controlling for T-stage. METHODS: We performed a retrospective cohort study at 2 tertiary care centers, examining 989 primary tumors from 814 immunocompromised patients (solid organ transplant: 259 [31.7%], chronic lymphocytic leukemia: 113 [13.9%]) and 6608 tumors from 4198 immunocompetent patients. Our primary outcome was the composite of disease-specific death or tumor metastasis ("poor outcomes"). RESULTS: Immunocompromised patients had 50% more high T-stage tumors (ie, Brigham and Women's Hospital stage T2b and T3), than immunocompetent patients (3.3% vs 4.9%, respectively; P < .001). Significant predictors of poor outcomes included tumor stage (sub hazards ratio [SHR], 14.8 for high T-stage tumors; 95% confidence interval [CI], 8.0-27.6; P < .001) and male sex (SHR, 2.3; 95% CI, 1.4-3.8; P = .002). Immune status was not a significant predictor (SHR, 1.04; 95% CI, 0.69-1.6; P = .85). LIMITATIONS: This study is retrospective. CONCLUSION: Although immunocompromised patients had 50% more high T-stage tumors than immunocompetent patients, immunocompromised patients had a similar chance of metastasis and disease-specific death when adjusting for T-stage in our cohort of primary tumors.

Adjuvant radiation following clear margin resection of high T-stage cutaneous squamous cell carcinoma halves the risk of local and locoregional recurrence: A dual-center retrospective study.

BACKGROUND: Although adjuvant radiation (ART) following clear margin surgery is recommended for select high-risk cutaneous squamous cell carcinomas, efficacy data are limited. OBJECTIVE: To evaluate the impact of ART on outcomes following clear margin surgery for high T-stage cutaneous squamous cell carcinomas. METHODS: A 20-year retrospective cohort study at 2 academic centers of high T-stage cutaneous squamous cell carcinomas (Brigham and Women's Hospital T2b or T3) with negative histologic margins post resection. Local recurrence (LR) and locoregional recurrence (LRR) were compared by whether tumors received ART or observation. RESULTS: A total of 508 tumors were included, of which 96 underwent ART (ART+). ART+ had a lower 5-year cumulative incidence of LR (ART+, 3.6% [95% CI, 1.6%-7.7%] vs ART-, 8.7% [95% CI, 6.3%-12.0%]) and LRR (ART+, 7.5% [95% CI, 4.4%-11.9%] vs ART-, 15.3% [95% CI, 11.9%-22.1%]). Recurrent tumors ≥6 cm or Brigham and Women's Hospital T3 tumors were classified as high-risk due to a higher 5-year cumulative incidence of LRR (High-risk, 26.3% [95% CI, 19.0%-35.7%]). High-risk tumors treated with ART had a lower 5-year cumulative incidence of LRR (ART+, 17.2% [95% CI, 11.9%-26.4%] vs ART-, 31.0% [95% CI, 26.1%-40.8%]). LIMITATIONS: Retrospective design, heterogeneous population, variations in radiation protocols. CONCLUSION: ART following clear margin surgery for high T-stage cutaneous squamous cell carcinomas resulted in half the risk of LR and LRR.

Approach to Oligometastatic Cancer in the Elderly Patient.

PURPOSE OF REVIEW: Patients with advanced cancer who have "oligometastatic" disease (OMD) have a limited burden of metastatic sites such that they may benefit from definitive therapies with limited toxicities. The incidence of cancers diagnosed in the elderly is increasing and treatment choices for them are often made because of their vulnerability to side effects. The present review discusses treatment of the elderly with OMD considering cancer outcomes and treatment toxicity. RECENT FINDINGS: Stereotactic body radiation therapy (SBRT) is emerging as a standard in the management of OMD because of its excellent local control and minimal toxicity. Phase II trials suggest that SBRT added to palliative therapy may improve overall survival and may delay the initiation of systemic therapy in OMD patients. Elderly patients are well represented in OMD studies SBRT will contribute significantly to the management of OMD in the elderly patient population by optimizing cancer control and limiting side effects.

Recent and Emerging Therapies for Cutaneous Squamous Cell Carcinomas of the Head and Neck.

OPINION STATEMENT: Cutaneous squamous cell carcinoma (cSCC) of the head and neck is typically managed with Mohs Micrographic Surgery (MMS) for cosmetic reasons. MMS also improves oncologic outcomes for high-risk tumors. Patients with certain high-risk subsets of the disease also benefit from adjuvant radiation therapy. The PD-1 inhibitor, cemiplimab, was recently approved for treatment of locally advanced and metastatic cSCC unamenable to curative surgery or radiation therapy after the drug demonstrated encouraging, durable response rates. Cemiplimab and other systemic immunotherapies are now being evaluated in clinical trials in the neoadjuvant and adjuvant settings as well. Localized immunotherapies are also being studied, including oncolytic viruses such as talimogene laherparepvec, a modified herpes simplex virus previously approved for the treatment of advanced cutaneous melanoma. Most importantly, multidisciplinary care is crucial in optimizing outcomes for patients with high-risk cSCC of the head and neck.

Impact of Cribriform Pattern and Intraductal Carcinoma on Gleason 7 Prostate Cancer Treated with External Beam Radiotherapy.

PURPOSE: We assessed the impact of cribriform pattern and/or intraductal carcinoma on Gleason 7 prostate cancer treated with external beam radiotherapy. METHODS: We evaluated men with Gleason 7 (Grade Groups 2 and 3) prostate cancer treated with dose escalated external beam radiotherapy with or without androgen deprivation. We reviewed biopsies for the presence of cribriform pattern and/or intraductal carcinoma. Study end points included biochemical recurrence-free, distant metastasis-free and disease specific survival. RESULTS: In the 237 patients median followup was 117 months (range 3 to 236). According to National Comprehensive Cancer Network® risk groups 24% of patients were at favorable intermediate risk, 53% were at unfavorable intermediate risk and 23% were at high risk. The rate of cribriform pattern without intraductal carcinoma, cribriform pattern with intraductal carcinoma, intraductal carcinoma without cribriform pattern and none of these morphologies was 36%, 13%, 0% and 51%, respectively. On multivariable analysis cribriform pattern with intraductal carcinoma (HR 4.22, 95% CI 2.08-8.53, p <0.0001), prostate specific antigen 10 to 20 ng/ml (HR 1.97, 95% CI 1.03-3.79, p=0.04) and prostate specific antigen greater than 20 ng/ml (HR 2.26, 95% CI 1.21-4.23, p=0.01) were associated with worse biochemical recurrence-free survival. On multivariable analysis only cribriform pattern with intraductal carcinoma was associated with inferior distant metastasis-free survival (HR 4.18, 95% CI 1.43-12.28, p=0.01) and disease specific survival (HR 14.26, 95% CI 2.75-74.04, p=0.0016). Factors associated with cribriform pattern with or without intraductal carcinoma included Grade Group 3, high risk group and 50% or more positive biopsy cores. When stratified by neither morphology present, cribriform pattern without intraductal carcinoma and cribriform pattern with intraductal carcinoma the differences in biochemical recurrence-free, distant metastasis-free and disease specific survival were statistically significant (p=0.00042, p=0.017 and p <0.0001, respectively). CONCLUSIONS: Cribriform pattern with intraductal carcinoma was associated with adverse outcomes in men with Gleason 7 prostate cancer treated with external beam radiotherapy while cribriform pattern without intraductal carcinoma was not so associated. Future studies may benefit from dichotomizing these 2 histological entities.

Validation of the 2022 National Comprehensive Cancer Network Risk Stratification for Cutaneous Squamous Cell Carcinoma.

Importance: The 2022 National Comprehensive Cancer Network (NCCN) reclassified cutaneous squamous cell carcinoma (CSCC) into low-, high-, and very high-risk groups to better risk stratify tumors. Mohs micrographic surgery (Mohs) or peripheral and deep en face margin assessment (PDEMA) became preferred surgical modalities for high- and very high-risk tumors. This new risk stratification and the recommendation for Mohs or PDEMA in high- and very high-risk groups have not been validated. Objective: To compare outcomes in very high-, high-, and low-risk NCCN groups of CSCCs and in CSCCs treated with Mohs or PDEMA compared with wide local excision (WLE). Design, Setting, and Participants: This retrospective cohort study of CSCCs was performed in 2 tertiary care academic medical centers. Patients 18 years or older and diagnosed between January 1, 1996, and December 31, 2019, at Brigham and Women's Hospital and Cleveland Clinic Foundation were included. Data were analyzed from October 20, 2021, to March 29, 2023. Exposures: NCCN risk group, Mohs or PDEMA, and WLE. Main Outcomes and Measures: Local recurrence (LR), nodal metastasis (NM), distant metastasis (DM), and disease-specific death (DSD). Results: A total of 10 196 tumors from 8727 patients were stratified by NCCN guidelines into low-, high-, and very high-risk groups (6003 [59.0%] men; mean [SD] age, 72.4 [11.8] years). Compared with the low-risk group, the high- and very high-risk groups demonstrated a greater risk of LR (high-risk subhazard ratio [SHR], 1.99 [95% CI, 1.21-3.27; P = .007]; very high-risk SHR, 12.66 [95% CI, 7.86-20.39; P < .001]), NM (high-risk SHR, 4.26 [95% CI, 1.28-14.23; P = .02]; very high-risk SHR, 62.98 [95% CI, 19.24-206.17; P < .001]), DM (high-risk SHR, 2.2 × 107 [95% CI, 4.7 × 103-1.1 × 1011; P < .001]; very high-risk SHR, 6.3 × 108 [95% CI, 1.4 × 105-2.9 × 1012; P < .001]), and DSD (high-risk SHR, 4.02 [95% CI, 1.18-13.71; P = .03]; very high-risk SHR, 93.87 [95% CI, 29.19-301.85; P < .001]). Adjusted 5-year cumulative incidence was significantly higher in very high- vs high- and low-risk groups for LR (9.4% [95% CI, 9.2%-14.0%] vs 1.5% [95% CI, 1.4%-2.1%] and 0.8% [95% CI, 0.5%-1.2%], respectively), NM (7.3% [95% CI, 6.8%-10.9%] vs 0.5% [95% CI, 0.4%-0.8%] and 0.1% [95% CI, 0.03%-0.3%], respectively), DM (3.9% [95% CI, 2.6%-5.6%] vs 0.1% [95% CI, 0.04%-0.2%] and 0.01% [95% CI, not applicable], respectively), and DSD (10.5% [95% CI, 10.3%-15.4%] vs 0.5% [95% CI, 0.4%-0.8%] and 0.1% [95% CI, 0.04%-0.3%], respectively). Compared with CSCCs treated with WLE, those treated with Mohs or PDEMA had lower risk of LR (SHR, 0.65 [95% CI, 0.46-0.90]; P = .009), DM (SHR, 0.38 [95% CI, 0.18-0.83]; P = .02), and DSD (SHR, 0.55 [95% CI, 0.36-0.84]; P = .006). Conclusions and Relevance: The findings of this cohort study suggest that the NCCN high- and very high-risk groups identify CSCCs at greatest risk for developing poor outcomes. Further, Mohs or PDEMA resulted in lower LR, DM, and DSD compared with WLE.

Neutrophil to Lymphocyte Ratio (NTLR) Predicts Local Control Failure and Overall Survival after Stereotactic Body Radiotherapy (SBRT) In Metastatic Sarcoma.

The neutrophil to lymphocyte ratio (NTLR) and absolute lymphocyte count (ALC) recovery are prognostic across many cancers. We investigated whether NLTR predicts SBRT success or survival in a metastatic sarcoma cohort treated with SBRT from 2014 and 2020 (N = 42). Wilcox Signed Rank Test and Friedman Test compare NTLR changes with local failure vs. local control (N = 138 lesions). Cox analyses identified factors associated with overall survival. If local control was successful, NLTR change was not significant (p = 0.30). However, NLTR significantly changed in patients local failure (p = 0.027). The multivariable Cox model demonstrated higher NLTR before SBRT was associated with worse overall survival (p = 0.002). The optimal NTLR cut point was 5 (Youden index: 0.418). One-year overall survival in SBRT metastatic sarcoma cohort was 47.6% (CI 34.3%-66.1%). Patients with an NTLR above 5 had a one-year overall survival of 37.7% (21.4%-66.3%); patients with an NTLR below 5 had a significantly improved overall survival of 63% (43.3%-91.6%, p = 0.014). Since NTLR at the time of SBRT was significantly associated with local control success and overall survival in metastatic sarcoma treated with SBRT, future efforts to reduce tumor inhibitory microenvironment factors and improved lymphocyte recovery should be investigated.

Intratumoral androgen biosynthesis associated with 3ß-hydroxysteroid dehydrogenase 1 promotes resistance to radiotherapy in prostate cancer.

Half of all men with advanced prostate cancer (PCa) inherit at least 1 copy of an adrenal-permissive HSD3B1 (1245C) allele, which increases levels of 3ß-hydroxysteroid dehydrogenase 1 (3ßHSD1) and promotes intracellular androgen biosynthesis. Germline inheritance of the adrenally permissive allele confers worse outcomes in men with advanced PCa. We investigated whether HSD3B1 (1245C) drives resistance to combined androgen deprivation and radiotherapy. Adrenally permissive 3ßHSD1 enhanced resistance to radiotherapy in PCa cell lines and xenograft models engineered to mimic the human adrenal/gonadal axis during androgen deprivation. The allele-specific effects on radiosensitivity were dependent on availability of DHEA, the substrate for 3ßHSD1. In lines expressing the HSD3B1 (1245C) allele, enhanced expression of DNA damage response (DDR) genes and more rapid DNA double-strand break (DSB) resolution were observed. A correlation between androgen receptor (AR) expression and increased DDR gene expression was confirmed in 680 radical prostatectomy specimens. Treatment with the nonsteroidal antiandrogen enzalutamide reversed the resistant phenotype of HSD3B1 (1245C) PCa in vitro and in vivo. In conclusion, 3ßHSD1 promotes prostate cancer resistance to combined androgen deprivation and radiotherapy by upregulating DNA DSB repair. This work supports prospective validation of early combined androgen blockade for high-risk men harboring the HSD3B1 (1245C) allele.

Neutrophil to lymphocyte ratio (NTLR) predicts local control and overall survival after stereotactic body radiotherapy (SBRT) in metastatic sarcoma.

The neutrophil to lymphocyte ratio (NTLR) and absolute lymphocyte count (ALC) recovery are prognostic across many cancers. We investigated whether NLTR predicts SBRT success or survival in a metastatic sarcoma cohort treated with SBRT from 2014 and 2020 (N = 42). Wilcox Signed Rank Test and Friedman Test compare NTLR changes with local failure vs. local control (N = 138 lesions). Cox analyses identified factors associated with overall survival. If local control was successful, NLTR change was not significant (p = 0.30). However, NLTR significantly changed in patients with local failure (p = 0.027). The multivariable Cox model demonstrated higher NLTR before SBRT was associated with worse overall survival (p = 0.002). The optimal NTLR cut point was 5 (Youden index: 0.418). One-year overall survival in SBRT metastatic sarcoma cohort was 47.6% (CI 34.3%-66.1%). Patients with an NTLR above 5 had a one-year overall survival of 37.7% (21.4%-66.3%); patients with an NTLR below 5 had a significantly improved overall survival of 63% (43.3%-91.6%, p = 0.014). Since NTLR at the time of SBRT was significantly associated with local control success and overall survival in metastatic sarcoma treated with SBRT, future efforts to reduce tumor inhibitory microenvironment factors and improve lymphocyte recovery should be investigated.

Coronary intravascular brachytherapy for in-stent restenosis: A review of the contemporary literature.

Intracoronary stent restenosis (ISR) is a clinically relevant challenge in the modern era. Heterogeneity in patient- and lesion-specific factors can further compound this clinical challenge. Coronary intravascular brachytherapy (IVBT) was the standard therapeutic approach for ISR prior to the advent of drug-eluting stents (DES). Despite prospective data describing the superiority of DES over IVBT for treating de novo ISR, IVBT remains a treatment option for patients with complex disease. The purpose of this review is to evaluate the historical and contemporary literature surrounding IVBT in order to elucidate its role in modern cardiac care and to describe opportunities for future investigations to improve patient selection. Herein, we provide a review of the contemporary literature describing IVBT as a safe and effective treatment option for patients with recurrent, refractory ISR after multilayer DES and no good surgical or mechanical option. Combination therapy with emerging technologies such as DCBs may further increase efficacy.

A Reappraisal of Definitive Chemoradiotherapy for Older Adults With Advanced Head and Neck Cancer.

BACKGROUND/AIM: Definitive treatment for locally advanced head and neck squamous cell carcinoma (LAHNSCC) is often compromised in older adults due to concerns about potential treatment toxicity intolerance. We reviewed our institutional experience with definitive management of older adults with LAHNSCC. PATIENTS AND METHODS: From our Institutional Review Board-approved registry, we identified patients aged >60 years with stage III-IV, M0 LAHNSCC (seventh/earlier editions of the American Joint Committee on Cancer classification) treated with definitive radiotherapy from 1993-2019. Indications for concurrent chemotherapy included T3-4 or N2-3 disease. Multivariable analysis using Fine and Gray regression was performed to identify risk factors associated with recurrence. The cumulative incidence method was used to calculate recurrence rates. RESULTS: Overall, 350 patients were identified: 223 aged 60-69, 82 aged 70-74, and 45 aged ≥75 years. Median follow-up was 36.3 months. Two-year recurrence rates were 13.7%, 20.2% and 34.8%, respectively; human papillomavirus-positive disease was present in 190 (85%), 44 (54%), and 25 (56%), respectively; and systemic therapy was given to 194 (87%), 64 (88%), and 23 (56%) patients, respectively. Factors significantly associated with increased risk of recurrence included age ≥75 years, Karnofsky performance status 70-80, clinical N2c-N3, and Charlson score 2-3. CONCLUSION: Patients aged ≥75 years received less aggressive therapy and experienced increased recurrence compared to younger patients. Outcomes for those aged 70-74 years were similar to younger patients treated with aggressive therapy, despite their inferior performance status/comorbidity, and such patients should not routinely be excluded from standard-of-care therapy. Further study is needed to optimize therapy for a redefined older adult (age ≥75 years) population.

Implications of Satellitosis or In-transit Metastasis in Cutaneous Squamous Cell Carcinoma: A Prognostic Omission in Cancer Staging Systems.

IMPORTANCE: Unlike Merkel cell carcinoma and melanoma, satellitosis or in-transit metastasis (S-ITM) is not incorporated into the current cutaneous squamous cell carcinoma (CSCC) staging systems. It is important to determine if the clinical outcomes of S-ITM are relevant to prognosis for patients with CSCC. OBJECTIVES: To evaluate the association of S-ITM with clinical outcomes in patients with CSCC and to determine its prognostic implications. DESIGN, SETTINGS, AND PARTICIPANTS: A dual-institution (Cleveland Clinic and Brigham and Women's Hospital) database was queried for patients who were treated for CSCC in 2010 to 2020. Patients who were node-negative and had S-ITM-the presence of dermal lesions between the primary tumor and first-echelon lymphatic nodal basins at any point in the disease course-were identified. Subcohorts of patients with T3N0 tumors, T4N0 tumors (bone invasive), N1 to 3, and M1 disease were identified for comparison. The American Joint Committee on Cancer staging system was used to define cancer stages. Data were analyzed from January 15 to March 31, 2021. MAIN OUTCOMES AND MEASURES: Pairwise comparison of CSCC recurrence and disease-specific survival in patients with and without S-ITM was performed using Cox proportional hazard modeling. Kaplan-Meier and Fine-Gray competing risk methods were used to estimate disease-specific survival and CSCC recurrence, respectively. RESULTS: In a total of 518 patients with CSCC, S-ITM was present in 72 (13.9 %) patients (median age [range], 73.9 [31.6-95.8] years; 59 [82%] men; 69 [96%] White non-Hispanic individuals; 25 [35%] patients with immunosuppression) who were node-negative. The subcohorts were composed of 341 patients with T3N0 cancer, 36 with T4N0, 70 with N1 to 3, and 19 with M1 disease. Pairwise comparisons between disease levels using Cox proportional hazard model demonstrated lower cumulative incidence of CSCC recurrence rates in the T3N0 (HR, 0.21; 95% CI, 0.14-0.30; P < .001) and T4N0 (HR, 0.36; 95% CI, 0.19-0.68; P = .001) cohorts compared with the S-ITM cohort. No significant difference was observed between patients who were node-positive and those with S-ITM (HR, 0.74; 95% CI, 0.48-1.14; P = .16). The 5-year disease-specific survival rates were 76% for T3N0, 64% for T4N0, 41% for S-ITM, and 39% for N1 to 3. Compared with the S-ITM cohort, DSS was significantly higher in the T3N0 (HR, 0.23; 95% CI, 0.15-0.35; P < .0001) and T4N0 (HR, 0.37; 95% CI, 0.19-0.76; P = .01) cohorts, and not significantly different in the node-positive (HR, 0.77; 95% CI, 0.84-3.93; P = .30) and metastatic cohorts (HR, 1.81; 95% CI, 0.84-3.93; P = .13). CONCLUSIONS AND RELEVANCE: This multi-institutional cohort study found that patients with CSCC and S-ITM appear to have clinical outcomes comparable to those of patients who are node-positive, and an increased risk of recurrence and worse survival compared with patients who have T3 and T4 disease. These outcomes are similar to those observed for Merkel cell carcinoma and melanoma. Given that S-ITM may be a powerful prognostic factor, it should be incorporated into clinical staging systems.

125I Interstitial brachytherapy with or without androgen deprivation therapy among unfavorable-intermediate and high-risk prostate cancer.

PURPOSE/OBJECTIVE(S): To determine if patients with unfavorable intermediate-risk (UIR), high-risk (HR), or very high-risk (VHR) prostate cancer (PCa) treated with 125I interstitial brachytherapy benefit from androgen deprivation therapy (ADT). MATERIALS/METHODS: We reviewed our institutional database of patients with UIR, HR, or VHR PCa, per 2018 NCCN risk classification, treated with definitive 125I interstitial brachytherapy with or without ADT from 1998-2017. Outcomes including biochemical failure (bF), distant metastases (DM), and overall survival (OS) were analyzed with the Kaplan-Meier method and Cox proportional hazards regression. PCa-specific mortality (PCSM) was analyzed with Fine-Gray competing-risk regression. RESULTS: Of 1033 patients, 262 (25%) received ADT and 771 (75%) did not. Median ADT duration was 6 months. By risk group, 764 (74%) patients were UIR, 219 (21%) HR, and 50 (5%) VHR. ADT was more frequently given to HR (50%) and VHR (56%) patients compared to UIR (16%; p<0.001), to older patients (p<0.001), corresponding with increasing PSA (p<0.001) and Grade Group (p<0.001). Median follow-up was 4.9 years (0.3-17.6 years). On multivariable analysis accounting for risk group, age, and year of treatment, ADT was not associated with bF, DM, PCSM, or OS (p≥0.05 each). CONCLUSION: Among patients with UIR, HR, and VHR PCa, the addition of ADT to 125I interstitial brachytherapy was not associated with improved outcomes, and no subgroup demonstrated benefit. Our findings do not support the use of ADT in combination with 125I interstitial brachytherapy. Prospective studies are required to elucidate the role of ADT for patients with UIR, HR, and VHR PCa treated with prostate brachytherapy.

Limited Toxicity of Hypofractionated Intensity Modulated Radiation Therapy for Head and Neck Cancer.

BACKGROUND/AIM: Hypofractionated radiation therapy is not commonly used in head and neck cancers (HNC) due to increased toxicity observed in historical cohorts. This study reviews our institutional experience using hypofractionated intensity modulated radiation therapy (H-IMRT) for HNC. PATIENTS AND METHODS: A retrospective cohort study of 56 patients with HNC treated with H-IMRT with ≥50 Gy in 20 fractions was conducted. The primary outcomes were acute and late toxicity. RESULTS: Two-year locoregional control was 87% and median overall survival was 46 months. There were no acute or late grade 4 or 5 toxicities. Acute grade 2 and 3 toxicity was seen in 79% (N=44) and 25% (N=14), respectively. Late grade 2 toxicity was seen in 9% (N=5). No patients required the placement of a feeding tube or tracheostomy. CONCLUSION: H-IMRT for the definitive or post-operative treatment of HNC using ≥50 Gy in 20 fractions appears safe and well tolerated with modest toxicity.

Treatment paradigms for oligometastatic pediatric cancers: a narrative review with a focus on radiotherapy approaches.

There is a growing body of prospective evidence describing an oligometastatic phenotype in adults for whom local metastasis-directed therapy can improve outcomes in select patients. However, a relative paucity of data for pediatric patients with oligometastatic disease creates challenges in choosing optimal treatment. The purpose of this review is to evaluate the literature surrounding pediatric oligometastatic disease and treatment, specifically focusing on the role of radiotherapy. A review of studies ranging from 2008 to 2020 was performed. The radiotherapy techniques evaluated included conventionally fractionated radiotherapy, stereotactic body radiotherapy (SBRT), and stereotactic radiosurgery (SRS). Our search yielded 6 studies evaluating conventionally fractionated radiotherapy, 9 studies of SBRT, and 3 studies of spine SRS. Metastasis-directed therapy for treatment of pediatric oligometastasis is generally well-tolerated, is associated with favorable local control, and is shown to improve event-free survival and progression-free survival (PFS) outcomes in select pediatric patients. Pediatric patients with oligometastatic disease may benefit from aggressive local therapy to metastatic sites in conjunction with a comprehensive treatment paradigm. Retrospective data have led to promising prospective trials that will further clarify patient selection and management. Additional data are needed to elucidate long term oncologic and toxicity outcomes.