Evaluating the impact of the degree of extranodal extension on outcomes in locally advanced oral cavity cancer

BACKGROUND

Evaluate whether extranodal extension (ENE) extent impacts outcomes in patients with oral cavity squamous cell carcinoma (OCSCC).

METHODS

From an institutional database, patients with OCSCC and pathologic ENE who received adjuvant treatment were included. Surgical slides were reviewed to confirm ENE extent. Multivariable Cox regression was used to relate patient/treatment characteristics with disease-free survival (DFS) and overall survival (OS). ENE was analyzed as both a dichotomous and continuous variable.

RESULTS

A total of 113 patients were identified. Between major (>2 mm) versus minor ENE (≤2 mm), there was no significant difference in DFS (HR 1.18, 95%CI 0.72-1.92, p = 0.51) or OS (HR 1.17, 95%CI 0.70-1.96, p = 0.55). There was no significant association between ENE as a continuous variable and DFS (HR 0.97 per mm, 95%CI 0.87-1.4, p = 0.96) or OS (HR 0.96 per mm, 95%CI 0.83-1.11, p = 0.58).

CONCLUSION

No significant relationship was seen between ENE extent and DFS or OS in individuals with OCSCC.

Oral Cavity Squamous Cell Carcinomas in Patients with a History of Oral Lichen Planus: Frequency and Outcomes

PURPOSE/OBJECTIVE(S)

Oral lichen planus (OLP) is an inflammatory condition which affects the mucous membranes of the oral cavity. While previous studies have described the association between OLP and development of oral cavity cancer, there is currently a paucity of literature examining the impact of this disease on treatment response and prognosis. As such, we present a retrospective cohort study of Oral cavity squamous cell carcinoma (OCSCC) patients with a history of OLP to explore the course of their disease.

MATERIALS/METHODS

Using an IRB approved tertiary care registry of head and neck cancer patients, we identified patients with OCSCC who had a prior diagnosis of OLP. The number of new primary tumors, rates of local (LF), regional (RF) and distant failure (DF), as well as overall survival (OS) were assessed using Cox proportional hazards and Kaplan Meier analysis for actuarial survival estimates.

RESULTS

Fifty-four patients with OCSCC and OLP were identified with 109 individual OCSCC diagnoses. Patients had a median age of 67 years, were predominantly female (n = 42, 77.8%) and never smokers (n = 29, 53.7%) with a median follow up after diagnosis of OCSCC of 46.5 months. Nine patients (16.7%) had a history of immunosuppression of whom 6 (11.1%) had chronic steroid use for treatment of OLP. Within the cohort, 33 (61.1%) of OLP patients had a single OCSCC, 11 (20.4%) had 2, and 10 (18.5%) had >3 separate tumors develop. The most common oral cavity subsites were oral tongue (n = 42, 38.5%), followed by alveolar ridge (n = 14, 12.8%) and gingiva (n = 13, 11.9%). Papillary SCC subtype was identified in 10.1%. 92.7% of tumors (n = 101) were treated with primary surgery, with 23 (21.1%) receiving adjuvant RT and 10 of those patients receiving concurrent chemotherapy. Among resected patients, pathologic stages were predominantly T1-2 (84.1%) and N0 (50% vs N1 15.6% and N2a-3 34.4%). The mean RT dose was 62 Gy in 32 fractions. Locoregional failure occurred in 24.8% of cancers (n = 27), with local and regional failure occurring in 13.8% (n = 15) and 11% (n = 12) of lesions, respectively. Recurrence free survival at 3 and 5 years was 75% and 70.3%, respectively, with overall survival at 3 and 5 years of 71.1% and 67%, respectively.

CONCLUSION

Patients with OCSCC and a history of OLP are predominantly female and never smokers. The tumors that develop in such patients are often early stage but a proportion of patients appear to be at higher risk of developing multiple malignancies and surveillance of this patient population to identify new tumors is crucial.

Stereotactic Body Radiation Therapy (SBRT) for Head and Neck Cancer Re-Irradiation: Should >180˚ Carotid Encasement or Dermal Involvement Remain an Exclusion Criteria?

PURPOSE/OBJECTIVE(S)

Patients with recurrent head and neck cancer (HNC) who present with carotid encasement (CE) >180˚ and skin involvement/abutment (SI/A) are often not considered for SBRT re-irradiation and are excluded from RTOG 3507. We reviewed our institutional experience of SBRT re-irradiation in such cases.

MATERIALS/METHODS

From an IRB approved registry, we identified previously irradiated HNC patients treated by SBRT with CE >180˚, SI/A, or use of bolus from 2013-2022. Toxicity as per CTCAEv4.0 and recurrence patterns were analyzed. The cumulative incidence of local progression was estimated with death as a competing risk. Survival analysis was performed with the Kaplan-Meier method.

RESULTS

Thirty-five patients were treated with SBRT to 37 sites with median follow up of 5.7 months (mo) (IQR 2.7-10.6). A total of 20 cases exhibited CE >180˚, 20 cases had SI/A, and 3 cases had both. The median time from prior radiation was 12.7 mo (range 1.9-144.1). Histology was squamous cell carcinoma in 89%. The site of SBRT was most commonly the neck (65%), 24% mucosa, 8% skull base, and 3% scalp. SBRT was delivered in 5 fractions every other day (62%) or 2 fractions per week (38%). 78% (N = 29) received ≥40 Gy while 22% (N = 8) received a lower dose. The cumulative incidence of local failure at 3 and 6 mo was 12.4% (95% CI 0.8-24.0) and 31.3% (95% CI 14.9-47.8), respectively. The median time of local and regional recurrence free survival was 7.0 and 4.9 mo. Median OS was 8.3 mo. Of the 20 cases with true SI, 40% (N = 8) completely resolved, 35% (N = 7) improved or had residual ulceration attributed to disease, and 25% (N = 5) had ulceration related to toxicity. There were no carotid bleeding events (CBE) related to SBRT, however 10% (N = 2) experienced fatal CBE related to progressive disease at 2.3 mo and 6.7 mo from SBRT. The rate of grade ≥2 treatment related skin toxicity was 19% (N = 7) and only occurred in those with pre-SBRT SI/A. These included a grade 2 neck wound and tracheostomy infection, a grade 3 infection, and two grade 3 soft tissue necrosis. One patient had cellulitis/meningitis related to scalp radiation, and one had an untreated SBRT wound as they transitioned to hospice. Dysphagia requiring PEG occurred in 5% (N = 2), one of which was related to CNX palsy. Six patients (17%) had post-SBRT nerve impairment including one each of grade 2 facial nerve paralysis, grade 2 brachial plexopathy, grade 3 CNVIII dysfunction, grade 3 CNX impairment, and two patients with grade 2 CNXII impairment.

CONCLUSION

SBRT for locally recurrent previously radiated HNC can provide effective local control in a patient population at high risk of morbidity and mortality from local disease progression. In patients who have >180˚ CE or SI/A, we observed non-trivial toxicity, but disease progression may have been more morbid. For appropriately counseled patients with limited treatment options, CE or SI/A may not be an absolute contraindication to SBRT re-irradiation.

Liver Stereotactic Body Radiation Therapy (SBRT) to Downstage Patients with Hepatocellular Carcinoma prior to Liver Transplant

PURPOSE/OBJECTIVE(S)

Orthotopic liver transplantation (OLT) marks the most successful treatment for hepatocellular carcinoma (HCC) patients meeting Milan criteria. The process of reducing the disease burden of HCC patients not currently meeting criteria for OLT with local therapy is referred to as "downstaging" and has proven to be a feasible approach. RTOG 1112 recently demonstrated the efficacy and acceptable toxicity of liver SBRT for treating HCC. However, limited data currently exists describing the efficacy of SBRT for downstaging HCC patients and facilitating OLT.

MATERIALS/METHODS

A single institution IRB approved prospective liver SBRT registry was surveyed for all patients outside of Milan criteria (1 lesion >5 cm; 2-3 lesions >3 cm) without vascular invasion or extrahepatic disease. Patients felt least likely to become OLT candidates with downstaging (age >80, >4 lesions, lesion >12 cm) were excluded. The primary endpoints were downstaging and OLT. Secondary endpoints were time to transplant, local control (LC), recurrence free survival (RFS) and overall survival (OS).

RESULTS

A total of 38 HCC patients with a median age of 65 years (range 28 - 80) met inclusion criteria. Median follow up was 14 months (IQR 3 - 35). At baseline, median KPS was 80 (range 60 - 100) with 16 Child-Pugh (CP) A (42%), 13 CP B (34%), and 9 CP C patients (24%). All patients were outside of Milan criteria and 25 patients (66%) were outside of UCSF criteria at time of SBRT. No patients had extrahepatic disease or vascular invasion. Median number of lesions, largest tumor size, and total sum of lesions were 2 (range 1 - 4), 5.0 cm (IQR, 4.0 - 6.5), and 6.6 cm (IQR 5.9 - 9.2), respectively. Prior to SBRT, 22 patients (58%) had received non-SBRT local therapy. At time of SBRT a variety of dose fractionation schedules were selected with a median BED10 of 78 (IQR 62 - 100). Concurrent sorafenib was used in 2 patients (8%). Following completion of SBRT, 21 patients (55%) were successfully downstaged at a median 3.0 months (IQR 1.9 - 6.1) after treatment, most frequently secondary to decrease in size of the largest lesion (86%). Twelve patients (32%) proceeded to undergo OLT at a median 7 months (IQR 3 - 14) after SBRT and 105 days (IQR 18 - 344) following successful downstaging. Of the 25 patients initially exceeding UCSF criteria, 7 (28%) underwent OLT. Among those receiving OLT, 5 patients (42%) remain alive without evidence of disease, 3 patients (25%) have recurred, 3 patients (33%) died within 2 years from transplant complications, and 1 patient (8%) died from an unrelated cause. LC at 2 years was 83%. Median RFS and OS for the overall cohort were 7 months (95% CI 0 - 21) and 24 months (95% CI 11 - 36), respectively. Among the transplant recipients, the median OS was 37 months (95% CI 30 - 44) compared to 15 months (95% CI 6 - 23) among those not receiving transplant.

CONCLUSION

With careful patient selection, liver SBRT serves as a feasible downstaging method to facilitate OLT in HCC patients.

Definitive Radiotherapy for the Treatment of Gross Disease in Unresected Differentiated Thyroid Cancer

PURPOSE/OBJECTIVE(S)

While surgery (with or without radioactive iodine (RAI)) is the mainstay of locoregional control in differentiated thyroid cancer (DTC), patients with unresectable disease present a clinical challenge. Uncontrolled disease in the neck can lead to substantial morbidity and mortality in DTC and obtaining locoregional control is vital to preserving quality of life and longevity. High dose definitive radiotherapy (RT) for gross disease in DTC is understudied. This study examines the efficacy of definitive RT in this setting.

MATERIALS/METHODS

From an IRB-approved registry of head and neck cancer cases treated at a tertiary care center over a period of 8 years (2014-2022), patients with incompletely resected or unresectable DTC including papillary, follicular, mixed, medullary, and poorly differentiated types were identified. All patients were treated to the neck and/or thyroid regions with visible gross disease to a definitive dose of radiation. The primary endpoint was local control within the radiated portal with a secondary endpoint of locoregional control within the neck.

RESULTS

A total of 31 patients were identified, of whom 74.2% were Caucasian. Fourteen were female (45.2%), and 17 (54.8%) were male. The median age was 68 years (range 26-90) and the median follow-up was 31 months. Histologically, 19 (61.3%) cases were papillary, 4 (12.9%) were follicular, 2 (6.5%) were mixed, 3 (9.7%) were medullary, and 3 (9.7%) were poorly differentiated. Among patients with non-medullary DTC 18 (69.2%) received prior RAI. Twelve patients were treated with radiation at initial diagnosis, while 19 patients were treated at the time of recurrence; two patients received concurrent chemotherapy. Twenty-eight patients (90.3%) were treated with IMRT and 3 (9.7%) were treated with SBRT. The median dose to the gross disease was 66 Gy (range 30-70.4) in 32 fractions (range 5-35). Overall, 5 patients (16.1%) experienced a locoregional failure after RT and all experienced failure in the RT portal. The actuarial infield control/locoregional control of radiation therapy at 3 and 5 years was 84.8% and 74.2%, respectively. Overall survival at 3 and 5 years was 68.5% and 47.4%, respectively. Among patients who had a locoregional failure after RT, 2 patients were salvaged with systemic therapy, 2 patients with surgery, and 1 patient with SBRT re-irradiation (40 Gy/5 fractions). The patient salvaged with SBRT remains without disease 8 months post-RT.

CONCLUSION

Definitive radiotherapy is a highly effective strategy to obtain durable control of unresected DTC. It should be standard for unresected disease and considered as a viable alternative for patients with borderline resectable disease for whom resection would be highly morbid.

Frameless Fractionated Stereotactic Radiosurgery for Brain Metastases: An Institutional Series of 145 Cases

PURPOSE/OBJECTIVE(S)

Cobalt-60 stereotactic radiosurgery (SRS) typically involves single fraction treatment with frame immobilization. However, large tumor size, proximity to critical structures, and prior radiation treatment sometimes necessitate fractionated SRS with mask immobilization. We present a large institutional experience with fractionated mask-based SRS for brain metastases.

MATERIALS/METHODS

In this single-institution, IRB-approved study, all patients treated with mask-based fractionated SRS for brain metastases from March 2017 to January 2023 were identified. The primary outcomes were 1- and 2-year local control (LC) by Kaplan-Meier method.

RESULTS

A total of 118 patients with a total of 145 metastases were treated. The median follow-up time was seven months. The median age at treatment was 64.1 years (range: 26-95 years). 55.9% of patients were female. The most common primary tumors were breast (25.5%), non-small cell lung (23.4%), small-cell lung (8.3%), and melanoma (8.3%). For most cases (59.3%), the indication for fractionation was retreatment. Large size (28.3%), critical location (9.7%), and medical comorbidity (2.1%) were other indications. For all cases, the mean maximal linear size was 34.9 mm and mean target volume was 15.6 cc. For cases fractionated due to size, the mean size was 43.9 mm and mean target volume was 23.8 cc. Median total dose was 2,700 cGy (range: 1,620-3,000), and median dose per fraction (fx) was 600 cGy (range: 405-900). The most common prescriptions were 3,000 cGy/5 fx (40.0% of patients) and 2500 cGy in 500 cGy per fraction (37.2% of patients). Mean maximum dose was 4,833 cGy (range: 2,920-7,500). For 75.2% of treatments, the prescription isodose line was 50 to 59% (mean, 56.9%). Target coverage was 100% in all but one case (99%). For lesions near the brainstem, mean brainstem maximum point dose (MPD) was 9.3 Gy ± 9.8 Gy and brainstem mean dose was 3.3 Gy ± 3.3 Gy. For lesions near the optic pathway, mean optic nerve MPD was 14.4 Gy ± 9.2, optic nerve mean dose was 6.4 Gy ± 5.4 Gy, mean optic chiasm MPD was 11.7 Gy ± 7.9 Gy, and optic chiasm mean dose was 5.4 Gy ± 4.7 Gy. 1-year LC was 88.2% and 2-year LC was 80.4%. When retreatments were excluded, 1-year LC was 98.0% and 2-year LC was 98.0%. 18% of patients had acute grade 1-2 toxicities (fatigue, headache, nausea, and/or alopecia), and one patient had acute grade 3 fatigue. There was no other grade 3+ acute toxicities. 14% of patients had grade 1-2 radiation necrosis (RN); there were no cases of grade 3+ RN.

CONCLUSION

Cobalt-60 frameless fractionated SRS for brain metastases offers excellent local control, rigorous sparing of critical structures, and minimal toxicity. Frameless fractionated SRS should be considered for large, retreated, or critically located metastases.

Using kV Triggered Imaging and Liver Dome Position to Reduce the Dosimetric Error Caused by Breath Hold Variability for Liver Stereotactic Body Radiation Therapy

PURPOSE/OBJECTIVE(S)

In a previous study, we demonstrated that manual gating using kV triggered imaging and liver dome position can reduce targeting errors caused by breath hold variability for liver stereotactic body radiation therapy (SBRT). In this study, we quantified the dosimetric error caused by breath hold variability and investigated the effect of liver dome gating on reducing dosimetric error.

MATERIALS/METHODS

Twenty-five liver SBRT patients treated with deep inspiration breath-hold were included in this IRB approved study. Volumetric modulated arc therapy was used to deliver 30-60 Gy in 1-5 fractions. To verify the breath-hold reproducibility during treatment, a KV triggered image was acquired at the beginning of each breath-hold. The liver dome position was visually compared with the expected upper/lower liver boundaries created by expanding/contracting the liver contour 5mm in the superior-inferior direction. If the liver dome position was within the boundaries, delivery continued; otherwise, beam was held manually and the patient was instructed to take another breath hold until the liver dome position was within boundaries. To calculate delivered dose, for each fraction, the treatment plan was divided into sub-beams, each corresponding to one breath hold using delivery log files. The triggered images were registered to the planning CT to determine the liver position during each breath hold. Dose delivered during each breath hold was calculated by shifting the isocenter of the sub-beam according to the liver position. Breath holds discarded by gating were excluded since no dose was delivered during these breath holds. Delivered fractional doses were compared with planned fractional doses using GTV D99 and liver Dmean. To estimate delivered dose without gating, the first "corrective" breath hold taken after the discarded breath holds was replaced with the prior discarded breath hold and dose calculation was repeated.

RESULTS

Seven hundred eleven triggered images from 91 treatment fractions were analyzed. Without gating, in 11 of the 91 fractions from 7 of the 25 patients, delivered GTV D99 reduced > 0.50 Gy from planned value (range 0.51-1.68 Gy, 3-10% of planned fractional GTV D99). Liver dome gating was able to detect/exclude irreproducible breath holds in 8 of the 11 fractions, increasing the delivered GTV D99 by 0.70 Gy per fraction on average (range 0.21-1.63 Gy). With liver dome gating, delivered fractional GTV D99 was comparable to planned value for all fractions (12.96 +/- 5.19 Gy vs 13.04 +/- 5.18 Gy, p > 0.05). Liver mean dose was not affected by breath hold variability or gating. Fractional liver Dmean was 2.26 +/- 1.19 Gy from plan, 2.27 +/- 1.21 Gy for delivery with gating and 2.27 +/- 1.20 Gy for delivery without gating.

CONCLUSION

Breath hold variability may cause tumor underdose. Liver dome gating using kV triggered imaging reduces dosimetric error and ensures tumor coverage for liver SBRT.

Partial Tongue Sparing without Marginal Failures: The Dosimetric Advantages for Oral Tongue Squamous Cell Carcinoma

PURPOSE/OBJECTIVE(S)

Due to a lack of internal barriers, many radiation oncologists believe whole tongue (WT) irradiation is warranted in the adjuvant setting for oral tongue cancer. Our institutional practice is to include the resection bed and flap with a 5-10 mm margin, attempting to spare unaffected oral tongue. We hypothesize that partial tongue (PT) irradiation, when feasible, results in decreased dose to surrounding normal structures without an increased risk of local recurrence (LR).

MATERIALS/METHODS

Patients with a new diagnosis of squamous cell carcinoma of the oral tongue treated with adjuvant IMRT between 2010 and 2021 were collected from an IRB approved database. PT was defined as <80% of residual tongue in the clinical target volume (CTV). Recurrence was deemed local if in the tongue or floor of mouth, and in field if within the CTV or marginal if outside of CTV. Mean dose to mandible, pharyngeal constrictors, and oral cavity were evaluated. Comparisons between groups were made using parametric one-way ANOVA. Multivariable linear regression was used to predict mean radiation dose. Local control and overall survival were estimated using Kaplan-Meier.

RESULTS

A total of 130 patients are included with median follow up 34.1 months (IQR 13.5-64.6). Radiation dose was 48-72 Gy in 24-36 fractions, most commonly 60-66 Gy in 30-33 fractions (84.6%). All were treated to oral cavity, and neck irradiation included bilateral 96 (72%), unilateral 31 (24%), and none 3 (4%). PT sparing was feasible in 91 (70%) and 39 (30%) required WT. Primary tumor stage in PT included 20 pT1, 50 pT2, 17 pT3, and 4 pT4, and WT included 3 pT1, 8 pT2, 15 pT3, and 13 pT4. 3-year local control for PT and WT was 96% and 87%, respectively. LR occurred in 14 patients overall (10.8%), 6.6% (6) of patients treated with PT and 20.5% (8) treated with WT (p = 0.072). Of the LR for PT, stage was 2 pT1, 3 pT2, and 1 pT3, and all occurred within the radiation field. Of the LR for WT, stage was 1 each of pT1 and pT2, 2 pT3, and 4 pT4. Overall survival was 57%, regional and distant recurrence was each 17.7%. Dosimetric analysis for PT vs WT is described in Table 1, demonstrating lower mean dose when the primary tumor CTV is limited to PT. Unilateral neck irradiation also resulted in a lower mandible [-8.5 Gy (-11.2 - -5.8)], pharyngeal constrictor [-14.3 Gy (-18.1 - -10.5)], and oral cavity [-9.0 Gy (-13.0 - -5.0)] dose (all p<0.001).

CONCLUSION

Limiting the primary tumor CTV to PT for adjuvant radiotherapy resulted in significant sparing of the mandible and pharyngeal constrictors, and a routinely lower oral cavity mean dose of ≥3.5 Gy. There was a low risk of LR when implementing PT, and all LR occurred in field. Given the increased sparing of normal structures, and low risk of LR outside of PT radiation field, sparing a portion of unaffected oral tongue should be considered.

Comparison of real-world outcomes following immunotherapy in recurrent or metastatic head and neck squamous cell carcinoma with outcomes of randomized controlled trials

OBJECTIVES

Evaluate outcomes of patients with recurrent or metastatic (R/M) head and neck squamous cell carcinoma (HNSCC) treated with immunotherapy (IO).

METHODS

Among patients with R/M HNSCC treated with IO in this retrospective single-institution cohort, Cox regression was used to compare overall survival (OS) for those with platinum-refractory disease and those treated in the first-line setting with OS from KEYNOTE-040/048, respectively. Multivariable Cox regression was used to identify predictors of OS.

RESULTS

There was no significant OS difference for those treated in the platinum-refractory setting when compared to patients on KEYNOTE-040 (HR = 1.22, p = 0.27), nor for the first-line setting compared to KEYNOTE-048 (HR = 1.23, p = 0.19). ECOG-PS 1 (HR = 2.00, p = 0.02) and ECOG-PS 2 (HR = 3.13, p < 0.01) were associated with worse OS. Higher absolute lymphocyte count (ALC) was associated with improved OS (HR = 0.93 per 100 cells/μL, p = 0.03).

CONCLUSIONS

Real-world outcomes of IO in R/M HNSCC are similar to outcomes in randomized control trials, with performance status and ALC correlating with OS.

Local Control With Single-Fraction Lung Stereotactic Body Radiotherapy is not influenced by Non-Small Cell Lung Cancer Histologic Subtype

INTRODUCTION/BACKGROUND

For early stage medically inoperable lung cancer treated with fractionated stereotactic body radiotherapy (SBRT), higher local failure is associated with squamous carcinoma (SqC) compared to adenocarcinoma (AC). This study explored whether histology influences single-fraction SBRT local control.

MATERIALS AND METHODS

We surveyed our prospective data registry from 12/2009 to 12/2019 for SF-SBRT cases with biopsy-proven AC or SqC only. Outcomes of interest included local (LF), nodal (NF), distant (DF) failure rates and overall survival (OS), as well as treatment-related toxicity.

RESULTS

For the 10-year interval surveyed, 113 patients met study criteria. There was no association between histology and dose received (34 Gy or 30 Gy). Median follow up was 22.9 months. Patient characteristics were balanced between histologic cohorts. Median tumor size was 1.9 cm. Comparing total AC vs. SqC cohorts, 2-year LF rates (%) were 7.3 vs. 9.6, respectively (P = .9805). In %, 2-year LF, NF, DF and OS rates for AC for 30 Gy and 34 Gy, respectively, were 10.8 vs. 6.4; 10.5 vs. 16.2; 15.8 vs. 13.0; 77.9 vs.71.2 (all P = non-significant). In %, 2-year LF, NF, DF, and OS rates for SqC for 30 Gy and 34 Gy, respectively, were 11.8 vs. 8.1; 5.9 vs. 18.0; 23.5 vs. 9.7; 70.6 vs. 77.1 (all P = non-significant). When considering toxicities, there were no grade 4/5 toxicities and no significant differences in any other toxicity rate by histology or dose.

CONCLUSION

SF-SBRT local control was not associated with histology, unlike fractionated schedules. This novel finding adds to the evolving understanding of this treatment schedule.

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.

Prognostic value of computed tomography scan detection of cartilage invasion in advanced laryngeal cancer treated with primary total laryngectomy

Background

We sought to determine whether detection of cartilage invasion (CI) by computed tomography predicts oncologic outcomes after primary total laryngectomy.

Methods

Retrospective cohort study comparing oncologic outcomes between radiologic versus pathologic diagnosis.

Results

Assessment of clear CI versus gestalt CI resulted in 84% versus 48% specificity, 90.9% versus 80.3% positive predictive value (PPV), 60.6% versus 80.3% sensitivity, 44.7% versus 48% negative predictive value (NPV), respectively. Disease‐free survival (DFS) was similar between cT4a and cT3/cT2 patients (p = 0.87). DFS trended towards superiority among pT3/pT2 versus pT4a patients (p = 0.18). DFS was similar among patients with CI on radiologist gestalt versus no CI (p = 0.94). Histologically confirmed CI was associated with a hazard ratio (HR) of 1.46 (p = 0.27), gestalt CI 1.13 (p = 0.70), and clear CI 1.61 (p = 0.10) for DFS.

Conclusion

Gestalt determination of CI results in high sensitivity but low specificity, while clear determination of CI results in moderate sensitivity and high specificity.

Primary Total Laryngectomy versus Organ Preservation for Locally Advanced T3/T4a Laryngeal Cancer

OBJECTIVE

Organ preservation (OP) treatment for advanced laryngeal cancer has increased compared to primary total laryngectomy. Our study compares oncologic and functional outcomes between these approaches.

STUDY DESIGN

Retrospective cohort study.

SETTING

Single tertiary care institution.

METHODS

Retrospective review of patients receiving primary total laryngectomy or OP for laryngeal cancer between 1/1/2000 and 12/31/2018.

RESULTS

A total of 118 patients received primary total laryngectomy and 119 received OP. Overall survival was similar between total laryngectomy and OP. When stratified by T stage, disease-free survival was worse among T3 patients receiving OP versus total laryngectomy. In T3 patients, 28 OP patients experienced local recurrence (28.9%) compared to 3 total laryngectomy patients (7.1%; p < 0.01). In total, 20 OP patients with local recurrence received salvage surgery. These patients had similar overall survival to patients who underwent initial total laryngectomy (TL). About 14 OP patients with local recurrence did not receive salvage surgery. About 89 (75.4%) TL patients achieved normal diet as compared to 64 (53.8%) OP patients (p < 0.001). In TL patients, 106 (89.8%) received primary or secondary tracheoesophageal-prosthesis, 82 (77.4%) of whom achieved completely understandable speech.

CONCLUSIONS

There was no difference in survival by treatment in T4 patients, possibly because of strict patient selection. However, disease-free survival was worse in T3 patients receiving OP, likely due to a high local recurrence rate. Approximately 40% of patients with local recurrence were not eligible for salvage laryngectomy. TL patients had comparable swallowing and speech outcomes with OP patients.

LEVEL OF EVIDENCE

3 Laryngoscope, 2022.

Defining high-risk elective contralateral neck radiation volumes for oropharynx cancer

BACKGROUND

To define the location of the initial contralateral lymph node (LN) metastasis in patients with oropharynx cancer.

METHODS

The location of the LN centroids from patients with oropharynx cancer and a single radiographically positive contralateral LN was defined. A clinical target volume (CTV) inclusive of all LN centroids was created, and its impact on dose to organs at risk was assessed.

RESULTS

We identified 55 patients of which 49/55 had a single contralateral LN in level IIA, 4/55 in level III, 1/55 in level IIB, and 1/55 in the retropharynx. Mean radiation dose to the contralateral parotid gland was 15.1 and 21.0 Gy, (p <0.001) using the modeled high-risk elective CTV and a consensus CTV, respectively.

CONCLUSIONS

We present a systematic approach for identifying the contralateral nodal regions at highest risk of harboring subclinical disease in patients with oropharynx cancer that warrants prospective clinical study.

Nasopharyngeal cancer: Incidence and prognosis of human papillomavirus and Epstein-Barr virus association at a single North American institution

BACKGROUND

The prognostication of Epstein-Barr virus (EBV) and human papillomavirus (HPV) status in nasopharyngeal cancer (NPC) is unclear.

METHODS

This retrospective study analyzed NPC from 2000 to 2019.

RESULTS

Seventy-eight patients were included: 43 EBV⁺ , 12 HPV⁺ , 23 EBV^- /HPV^- , and 0 EBV⁺ /HPV⁺ . All p16⁺ tumors were also positive for HPV-CISH. Baseline characteristics were not different between groups except age, N-classification, and Karnofsky Performance Scale (KPS) (p < 0.05). For EBV⁺ , HPV⁺ , and EBV^- /HPV^- respectively, 3-year overall survival (OS) was 89.9%, 69.8%, and 52.5% (p = 0.006). EBV^- /HPV^- status was significantly associated with worse OS but not freedom from progression (FFP) on univariate analysis, and did not remain a significant predictor of OS after adjusting for KPS, age, and group stage.

CONCLUSIONS

EBV⁺ NPC tumors were seen in younger, healthier patients than HPV⁺ and EBV^- tumors, and there were no cases of coinfection. The association of viral status with OS was insignificant after adjusting for KPS and age.

Updated Outcomes of Split Course Radiotherapy in Elderly or Infirm Patients With Advanced Cancers of the Head and Neck

BACKGROUND/AIM

Head and neck cancers are often treated with extended courses of radiotherapy (RT), which may prove excessively toxic for frail patients. Split course RT (SCRT) delivers two courses of RT separated by 4-6 weeks, personalizing treatment intensity based on response. In this study, we present our updated experience using this technique.

PATIENTS AND METHODS

From a single institution database, we identified patients considered for SCRT. For patients undergoing a second course of RT, cumulative incidence of locoregional recurrence (LRR) and overall survival (OS) are reported.

RESULTS

A total of 98 patients were included, of whom seventy-five percent underwent a second course of RT. The most common fractionation was 30 Gy in 10 fractions for each course, with a median cumulative dose of 60 Gy. In those undergoing a second course of RT, median OS was 9.7 months and cumulative incidence of LRR at 6, 12, and 24 months was 17.0%, 23.1%, and 29.4%, respectively.

CONCLUSION

SCRT offers an attractive treatment paradigm to personalize radiation intensity based on patient tolerance, while maintaining reasonable safety and efficacy in those unfit for standard full course RT.

Ten-Year Experience in Implementing Single-Fraction Lung SBRT for Medically Inoperable Early-Stage Lung Cancer

PURPOSE

To review 10 years of using single-fraction lung stereotactic body radiation therapy (SF-SBRT) for medically inoperable peripheral early-stage lung cancer.

METHODS AND MATERIALS

An institutional review board-approved prospective lung SBRT data registry was surveyed until the end of December 2019 for all patients receiving SF-SBRT with minimum 6-month follow-up. Doses used were either 34 Gy or 30 Gy. Outcomes of interest included rates of local failure and overall survival (OS), as well as treatment-related toxicity graded per Common Terminology Criteria for Adverse Events version 3.0.

RESULTS

A total of 229 patients met the study criteria. Patient characteristics included female sex (55%); median age, 74.6 years (range, 47-94); and median Karnofsky Performance Status 80 (range, 50-100). Tumor characteristics included median diameter, 1.6 cm (range, 0.7-4.1); median positron emission tomography standardized uptake value maximum 6.1 (range, 0.8-24.3); and 63.6% of patients biopsied. SF-SBRT dose was 34 Gy in 72.1% cases and 30 Gy in 27.9%, with patient and tumor characteristics balanced between cohorts. Overall median follow-up times for 30 Gy and 34 Gy were 36.7 and 17.2 months, respectively (P < .0001). At analysis, 55.9% patients were alive. Two (0.9%) patients developed grade 3 toxicities, and none had grade 4/5 toxicities. Grades 1 to 2 pneumonitis and chest wall toxicity were seen in 7% and 12.7% patients, respectively. Median overall survival was 44.1 months. Rates of 2-year local, nodal, and distant failure were 7.3%, 9.4%, and 12.2%, respectively. There were no significant differences in outcomes by dose.

CONCLUSIONS

This is the largest institutional series to date reporting on SF-SBRT outcomes for medically inoperable peripheral early-stage lung cancer and the first to report on a decade's experience in implementing this schedule. Outcomes from this analysis are comparable to published results from 2 randomized trials and validate the use of this schedule in routine practice. In the absence of phase 3 trials, this study should encourage increased use of SF-SBRT for inoperable tumors.

Outcomes of Post-Operative Treatment with Concurrent Chemoradiotherapy (CRT) in High-Risk Resected Oral Cavity Squamous Cell Carcinoma (OCSCC): A Multi-Institutional Collaboration

Adjuvant chemoradiation (CRT), with high-dose cisplatin remains standard treatment for oral cavity squamous cell carcinoma (OCSCC) with high-risk pathologic features. We evaluated outcomes associated with different cisplatin dosing and schedules, concurrent with radiation (RT), and the effect of cumulative dosing of cisplatin. An IRB-approved collaborative database of patients (pts) with primary OCSCC (Stage I–IVB AJCC 7th edition) treated with primary surgical resection between January 2005 and January 2015, with or without adjuvant therapy, was established from six academic institutions. Patients were categorized by cisplatin dose and schedule, and resultant groups compared for demographic data, pathologic features, and outcomes by statistical analysis to determine disease free survival (DFS) and freedom from metastatic disease (DM). From a total sample size of 1282 pts, 196 pts were identified with high-risk features who were treated with adjuvant CRT. Administration schedule of cisplatin was not significantly associated with DFS. On multivariate (MVA), DFS was significantly better in patients without perineural invasion (PNI) and in those receiving ≥200 mg/m² cisplatin dose (p < 0.001 and 0.007). Median DFS, by cisplatin dose, was 10.5 (<200 mg/m²) vs. 20.8 months (≥200 mg/m²). Our analysis demonstrated cumulative cisplatin dose ≥200 mg/m² was associated with improved DFS in high-risk resected OCSCC pts.

Failure rate in the untreated contralateral node negative neck of small lateralized oral cavity cancers: A multi-institutional collaborative study

OBJECTIVES

The importance of treating the bilateral neck in lateralized small oral cavity squamous cell carcinoma (OCC) is unclear. We sought to define the incidence and predictors of contralateral neck failure (CLF) in patients who underwent unilateral treatment.

MATERIALS AND METHODS

We performed a multi-institutional retrospective study of patients with pathologic T1-T2 (AJCC 7th edition) OCC with clinically node negative contralateral neck who underwent unilateral treatment with primary surgical resection ± adjuvant radiotherapy between 2005 and 2015. Incidence of CLF was estimated using the cumulative incidence method. Clinicopathological factors were analyzed by univariate (UVA) and multivariate analysis (MVA) for possible association with CLF. Kaplan-Meier analysis was used to estimate overall survival (OS).

RESULTS

176 patients were evaluated with a median of 65.9 months of follow-up. Predominant pathologic T-stage was T1 (68%), 8.5% of patients were N1, 2.8% were N2b. Adjuvant radiotherapy was delivered to 17% of patients. 5-year incidence of CLF was 4.3% (95% CI 1.2-7.4%). Depth of invasion (DOI) > 10 mm and positive ipsilateral neck node were significant predictors for CLF on UVA. DOI > 10 mm remained significant on MVA (HR = 6.7, 95% CI 1.4-32.3, p = 0.02). The 2- and 5-year OS was 90.6% (95% CI 86.2-95.0%) and 80.6% (95% CI 74.5-86.8%), respectively.

CONCLUSION

Observation of the clinically node negative contralateral neck in small lateralized OCC can be a suitable management approach in well selected patients, however caution should be applied when DOI upstages small but deeply invasive tumors to T3 on 8th edition AJCC staging.

Stereotactic body radiotherapy for the treatment of oligometastatic gynecological malignancy in the abdomen and pelvis: A single-institution experience

PURPOSE/OBJECTIVES

Metastasis-directed therapy with stereotactic body radiotherapy (SBRT) in the setting of oligometastatic disease is a rapidly evolving paradigm given ongoing improvements in systemic therapies and diagnostic modalities. However, SBRT to targets in the abdomen and pelvis is historically associated with concerns about toxicity. The purpose of this study was to evaluate the safety and efficacy of SBRT to the abdomen and pelvis for women with oligometastases from primary gynecological tumors.

MATERIALS/METHODS

From our IRB-approved registry, all patients who were treated with SBRT between 2014 and 2020 were identified. Oligometastatic disease was defined as 1 to 5 discrete foci of clinical metastasis radiographically diagnosed by positron emission tomography (PET) and/or computerized tomography (CT) imaging. The primary endpoint was local control at 12 months. Local and distant control rates were estimated using the Kaplan-Meier method. Time intervals for development of local progression and distant progression were calculated based on follow up visits with re-staging imaging. Acute and late toxicity outcomes were determined based on Common Terminology Criteria for Adverse Events (CTCAE) version 5.0.

RESULTS

We identified 34 women with 43 treated lesions. Median age was 68 years (range 32-82), and median follow up time was 12 months (range 0.2-54.0). Most common primary tumor sites were ovarian (n=12), uterine (n=11), and cervical (n=7). Median number of previous lines of systemic therapy agents at time of SBRT was 2 (range 0-10). Overall, SBRT was delivered to 1 focus of oligometastasis in 29 cases, 2 foci in 2 cases, 3 foci in 2 cases, and 4 foci in 1 case. All patients were treated comprehensively with SBRT to all sites of oligometastasis. Median prescription dose was 24 Gy (range 18-54 Gy) in 3 fractions (range 3-6) to a median prescription isodose line of 83.5% (range 52-95). Local control by lesion at 12 and 24 months was 92.5% for both time points. Local failure was observed in three treated sites among two patients, two of which were at 11 months in one patient, and the other at 30 months. Systemic control rate was 60.2% at 12 months. Overall survival at 12 and 24 months was 85% and 70.2%, respectively. Acute grade 2 toxicities included nausea (n=3), and there were no grade > 3 acute toxicities. Late grade 1 toxicities included diarrhea (n=1) and fatigue (n=1), and there were no grade > 2 toxicities.

CONCLUSION

SBRT to oligometastatic gynecologic malignancies in the abdomen and pelvis is feasible with encouraging preliminary safety and local control outcomes. This approach is associated with excellent local control and low rates of toxicity during our follow-up interval. Further investigations into technique, dose-escalation and utilization are warranted.

Does Motion Management Technique for Lung SBRT Influence Local Control? A Single Institutional Experience Comparing Abdominal Compression to Breath-Hold Technique

PURPOSE

Abdominal compression (COMP) and breath-hold with an active breathing coordinator (ABC) device are 2 different respiratory motion management techniques used in lung stereotactic body radiation therapy (SBRT) practice. We compared local failure (LF) results for COMP versus ABC.

METHODS AND MATERIALS

We surveyed our institutional review board-approved prospective registry for patients who were treated with SBRT for either a primary lung cancer (PRIME) or an oligometastatic (OLIGO) diagnosis with a minimum of 6 months' follow-up to determine their rates of local failure by motion management modality.

RESULTS

From October 2003 to July 2014, 873 patients with 931 lesions were treated. Patient characteristics included: 455 (52.1%) female; median age of 73 years (range, 37-97); median Karnofsky performance status (KPS) of 80 (range, 40-100); and median BMI of 26.2 (range, 12.1-56.3). Tumor characteristics included: median tumor size of 2.2 cm (range, 0.7-10.0); median maximum standardized uptake value from positron emission tomography PET SUVmax of 7.5 (range, 0.8-59); 234 (25.4%) were central lesions; 830 (89.2%) lesions were PRIME; and 101 (10.8%) were OLIGO. Median follow-up and SBRT dose were 16.4 months and 50 G in 5 fractions, respectively. Overall crude rate of LF was 9.9%. Use of ABC was not associated with increased LF compared with COMP: hazard ratio (HR) = 1.043 (95% CI 0.48-2.29; P = .92). Three-year actuarial rates of LF for ABC versus COMP were 13.8% and 16.5%, respectively. After stratifying by OLIGO/PRIME, neither ABC nor COMP was significantly associated with LF. Central location may be associated with LF with ABC (HR = 2.087, P = .066). On univariate analysis, BMI, tumor size, PET SUV max and central location were associated with failure, with size the most significant.

CONCLUSIONS

LF rates after lung SBRT were not influenced by form of motion control overall or when stratified by tumor type. Further study on LF rates for central tumors where ABC is used is warranted.

Identifying an oligometastatic phenotype in HPV-associated oropharyngeal squamous cell cancer: Implications for clinical trial design

OBJECTIVES

Patients with human papillomavirus (HPV) associated squamous cell carcinoma of the oropharynx (SCC-OP) have improved overall survival (OS) after distant metastasis (DM) compared to HPV negative patients. These patients may be appropriate candidates for enrollment on clinical trials evaluating the efficacy of metastasis-directed therapy (MDT). This study seeks to identify prognostic factors associated with OS after DM, which could serve as enrollment criteria for such trials.

MATERIALS AND METHODS

From an IRB approved multi-institutional database, we retrospectively identified patients with HPV/p16 positive SCC-OP diagnosed between 2001 and 2018. Patterns of distant failure were assessed, including number of lesions at diagnosis and sites of involvement. The primary outcome was OS after DM. Prognostic factors for OS after DM were identified with Cox proportional hazards. Stepwise approach was used for multivariable analysis.

RESULTS

We identified 621 patients with HPV-associated SCC-OP, of whom 82 (13.2%) were diagnosed with DM. Median OS after DM was 14.6 months. On multivariable analysis, smoking history and number of lesions were significantly associated with prolonged OS. Median OS after DM by smoking (never vs ever) was 37.6 vs 11.2 months (p = 0.006), and by lesion number (1 vs 2-4 vs 5 or more) was 41.2 vs 17.2 vs 10.8 months (p = 0.007).

CONCLUSION

Among patients with newly diagnosed metastatic HPV-associated SCC-OP, lesion number and smoking status were associated with significantly prolonged overall survival. These factors should be incorporated into the design of clinical trials investigating the utility of MDT, with or without systemic therapy, in this population.

Evaluating compliance with process-related quality metrics and survival in oral cavity squamous cell carcinoma: Multi-institutional oral cavity collaboration study

BACKGROUND

Process-related measures have been proposed as quality metrics in head and neck cancer care. A recent single-institution study identified four key metrics associated with increased survival. This study sought to validate the association of these quality metrics with survival in a multi-institutional cohort.

METHODS

Multicenter retrospective study of patients with oral cavity squamous cell (1/2005-1/2015). Baseline patient and disease characteristics and compliance with quality metrics was evaluated. Association between compliance with quality metrics with overall survival (OS), disease-free survival (DFS), and disease-specific survival (DSS) was evaluated using Cox proportional hazards models.

RESULTS

Failure to comply with two or more of the quality metrics was associated with worse OS, DFS, and DSS. Adherence to all or all but one of the quality metrics was found to be associated with improved survival.

CONCLUSIONS

Process-related quality metrics are associated with increased survival in patients with oral cavity squamous cell carcinoma in a multi-institutional cohort.

Clinical management of emerging sinonasal malignancies

Several emerging sinonasal malignancies have recently been described in the pathology literature. Although not all distinctly classified by the World Health Organization, these rare tumors present a management challenge to surgeons and oncologists. While prior studies have summarized histologic details, a clinically focused review is currently lacking in the literature. This review describes the presentation, histopathology, imaging, treatment, and prognosis of newly described or recently evolving sinonasal malignancies while highlighting the distinguishing features of these entities. It includes teratocarcinosarcoma, human papillomavirus-related multiphenotypic carcinoma, biphenotypic sinonasal sarcoma, sinonasal renal cell-like adenocarcinoma, NUT-midline carcinoma, squamous cell carcinoma associated with inverted papilloma, sinonasal undifferentiated carcinoma, and INI-1-deficient sinonasal carcinoma. By describing the diagnosis, treatment, and prognosis of these recently defined entities, this clinical review aims to help guide oncologists in the clinical management of these patients.

Impact of routine surveillance imaging on detecting recurrence in human papillomavirus associated oropharyngeal cancer

OBJECTIVES

This study examines the utility of surveillance imaging in detecting locoregional failures (LRF), distant failures (DF) and second primary tumors (SPT) in patients with human papillomavirus (HPV) associated oropharyngeal cancer (OPC) after definitive chemoradiotherapy (CRT).

METHODS AND MATERIALS

An institutional database identified 225 patients with biopsy proven, non- metastatic HPV+ OPC treated with definitive CRT between 2004 and 2015, whose initial post-treatment imaging was negative for disease recurrence (DR). Two groups were defined: patients with <2 scans/year Group 1 and patients with ≥2 scans/year Group 2. The Mann-Whitney test or Chi-square was used to determine differences in baseline characteristics between groups. Fine & Gray regression was used to detect an association between imaging frequency, DR and diagnosis of SPT.

RESULTS

Median follow up was 40.8 months. 30% of patients had ≥T3 disease and 90% had ≥ N2 disease (AJCC 7th edition). Twenty one failures (9.3%) were observed, 7 LRF and 15 DF. Six LRF occurred within 24 months and 14 DF occurred within 36 months of treatment completion. Regression analysis showed Group 2 had increased risk of DR compared to Group1 (HR 10.3; p = 0.002) albeit with more advanced disease at baseline. Five SPT were found (2 lung, 2 esophagus, and 1 oropharynx) between 4.5 and 159 months post-CRT.

CONCLUSION

Surveillance imaging seems most useful in the first 2-3 years post treatment, and is particularly important in detecting DF. Surveillance scans for SPT has a low yield, but should be considered for those meeting lung cancer screening guidelines.

Validation of RTOG 0813 Proximal Bronchial Tree Constraints for Pulmonary Toxicity With Stereotactic Body Radiation Therapy for Central Non-small Cell Lung Cancer

PURPOSE

Clinical validation of protocol-specified dosimetric constraints for the proximal bronchial tree (PBT) is limited for central non-small cell lung cancer treated with stereotactic body radiation therapy. We sought to validate Radiation Therapy Oncology Group (RTOG) PBT constraints with a large institutional data set.

METHODS AND MATERIALS

Lesions ≤2 cm from the PBT treated with definitive stereotactic body radiation therapy from 2009 to 2016 were identified from a prospective registry of 1462 patients. Every PBT dose and volume combination, ranging from 0 cGy to 8000 cGy in increments of 10 cGy and volumes ranging from 0.03 cm³ to 50 cm³ in increments of 0.03 cm³, was analyzed. The sensitivity and specificity of these endpoints for identifying pulmonary toxicity were calculated. Pulmonary toxicity was classified as pneumonitis or nonpneumonitis toxicity (NPT) (fistula, stenosis, necrosis, hemoptysis, clinically significant pleural effusion). The optimal dosimetric predictor was chosen by calculation of F-score (highest sensitivity and specificity).

RESULTS

The study included 132 patients, with 26.0-month median follow-up. Eight grade ≥2 NPT (2 grade 5) and 8 grade 2 pneumonitis toxicities were observed. The PBT dosimetric endpoint with the highest F-score for identification of grade 2 to 5 NPT was D0.03cc ≤5000 cGy and that for grade 3 to 5 NPT was D0.33cc ≤4710 cGy, with sensitivity and specificity of 87.5% and 76.6% and 100.0% and 85.7%, respectively. Applying the RTOG 0813 PBT constraints to our data set achieved a sensitivity and specificity of 33.3% and 92.1% for D4cc ≤1800 cGy and 37.5% and 92.7% for D0.03cc ≤5250 cGy for identification of grade 2 to 5 NPT. A PBT dosimetric correlation for pneumonitis toxicity could not be identified.

CONCLUSIONS

This novel dosimetric analysis validates current RTOG constraints and emphasizes high-dose, small-volume constraints as better predictors for NPT. We demonstrated that a slightly lower maximum point dose PBT constraint may be optimal for identification of NPT. Validation of these findings in a larger cohort of patients with longer follow-up is necessary.

Outcomes in intermediate-risk squamous cell carcinomas treated with Mohs micrographic surgery compared with wide local excision

BACKGROUND

Brigham and Women's Hospital stage T2a squamous cell carcinomas, demonstrating a single high-risk feature, have a low risk of metastasis and death but an increased risk of local recurrence. Little evidence exists for the best treatment modality and associated outcomes in T2a squamous cell carcinoma.

OBJECTIVE

We aimed to compare outcomes for T2a squamous cell carcinoma treated by Mohs micrographic surgery compared with wide local excision with permanent sections.

METHODS

Retrospective review of an institutional review board-approved single-institution registry of T2a squamous cell carcinoma.

RESULTS

Three hundred sixty-six primary T2a tumors were identified, including 240 squamous cell carcinomas (65.6%) treated with Mohs micrographic surgery and 126 (34.4%) treated with wide local excision. A total of 32.5% of patients were immunosuppressed and mean oncologic follow-up was 2.8 years. Local recurrence was significantly more likely after wide local excision (4.0%) than after Mohs micrographic surgery (1.2%) (P = .03). Multiple logistic regression demonstrated immunocompromised state (odds ratio [OR] 5.1; 95% confidence interval [CI] 1.1-23.3; P = .03) and wide local excision (OR 4.8; 95% CI 1.1-21.6; P = .04) associated with local recurrence; and wide local excision (OR 7.8; 95% CI 2.4-25.4; P < .001), high-risk head and neck location (OR 8.3; 95% CI 1.8-38.7; P = .004), and poor histologic differentiation (OR 4.7; 95% CI 1.4-15.4; P = .03) associated with poor outcomes (overall recurrence or disease-specific death).

CONCLUSION

Mohs micrographic surgery provides improved outcomes in Brigham and Women's Hospital T2a squamous cell carcinoma.

Tumor Volume Useful Beyond Classic Criteria in Selecting Larynx Cancers For Preservation Therapy

OBJECTIVE

To investigate the association between tumor volume and locoregional failure (LRF) after concurrent chemoradiation (CCRT) for locally advanced larynx cancer (LC).

METHODS

This is a retrospective cohort study from 2009 to 2014 identified from an institutional review board-approved registry. Fifty-nine of 68 patients with locally advanced larynx cancer treated with definitive CCRT who had available imaging for review were identified. The main endpoint to be assessed was the association between gross tumor volumes (GTV; T = total, P = primary, N = nodal) and LRF. Receiver operative characteristic (ROC) curves were used to investigate diagnostic accuracy.

RESULTS

Twenty LRFs were observed, resulting in a 2-year LRF rate of 39% (95% CI, 23-52%). On UVA, the GTV-T (P = .01), GTV-P (P = .05), and GTV-N (P = .04) were statistically significant predictors of LRF. Furthermore, age, smoking status, N-stage, larynx subsite, and tracheostomy/feeding tube dependence were potentially associated with LRF (P < .3), whereas T-stage (T3-4 vs. T2) was not (HR 1.05, 95% CI, 0.38-2.91, P = .92). In the multivariable model, GTV-P (HR 1.022, 95% CI, 0.999-1.046, P = .07) and GTV-N (HR 1.053, 95% CI, 1.0004-1.108, P = .05) were the two most impactful covariates on the model's R² . ROC analysis suggested an optimal cut point of 12 cc in the GTV-T. The 2-year LRF for GTV-T > 12 cc was 64.2% and ≤ 12 cc was 16.4%, P = .006.

CONCLUSION

GTV is associated with LRF after definitive CCRT for LC. Patients with bulky primary and/or nodal tumors may be better served with upfront surgical resection regardless of T-stage. Further investigation into the safety of larynx preservation for low-volume T4 tumors can be considered.

LEVEL OF EVIDENCE

4 Laryngoscope, 130:2372-2377, 2020.

Long-term complications and reconstruction failures in previously radiated breast cancer patients receiving salvage mastectomy with autologous reconstruction or tissue expander/implant-based reconstruction

Salvage mastectomy (SM) is the standard of care for patients with local recurrence (LR) after breast conservation therapy (BCT), often with immediate reconstruction. Complications of reconstruction are a concern for these patients, and long-term data are limited. We sought to compare rates of complications requiring re-operation (CRR) and reconstruction failure (RF) between autologous reconstruction (AR) and tissue expander/implant reconstruction (TE/I). Patients with locally recurrent breast cancer after BCT, treated with SM and immediate AR or TE/I between 2000 and 2008, were identified. CRR was defined as unplanned return to operating room for wound infection, dehiscence, necrosis (including flap, skin, or fat), hematoma, or hernia (for AR) and extrusion, leak, or capsular contracture (for TE/I). RF was defined as conversion to another reconstruction technique or to flat chest wall. This study included 103 patients with 107 reconstructions. Median follow-up was 6.6 years. CRR and RF were significantly higher with TE/I (n = 34) compared to AR (n = 73) at 5 years (50.9% vs 25.5%; P = 0.02) and (42.1% vs 5.8%; P < 0.001). On univariate analysis (UVA), TE/I (HR = 2.14; P = 0.02) and diabetes (HR = 5.10; P = 0.007) were significant predictors for CRR. On UVA, TE/I (HR = 7.30; P < 0.001) and older age at reconstruction (HR = 1.03; P = 0.003) were significant predictors for RF. In this population of previously irradiated patients, TE/I was associated with significantly higher CRR and RF. Complications continue to occur up to 10 years after TE/I. AR should be considered in appropriately selected patients, though TE/I may remain a reasonable option in patients without high-risk factors for surgical complications.

Five-year outcomes of sparing level IB in node-positive, human papillomavirus-associated oropharyngeal carcinoma: A safety and efficacy analysis

INTRODUCTION

The conformality of modern intensity modulated radiation therapy (IMRT) allows avoidance of the submandibular glands (SMG) in select patients, potentially improving late xerostomia. This study explores the safety and efficacy of this approach in select oropharyngeal carcinoma (OPC) patients.

METHODS

Patients with T1-2N+ human papillomavirus (HPV)-associated OPC treated with definitive IMRT at one institution from 2009 to 2014 were identified. Patients were divided into 3 groups: bilateral level IB targeted (A, n = 16), a single level IB targeted (B, n = 61), and bilateral IB spared (C, n = 9). Outcomes were reviewed to identify the rate of level IB regional recurrence. Odds ratios were calculated for xerostomia between groups.

RESULTS

Level Ib was targeted in 93 instances (54.1%) and avoided in 79 instances (45.9%). Mean SMG doses were significantly lower when level IB was spared compared to when targeted (37.5 Gy vs 67.5 Gy; P < 0.0001). Median doses to oral cavity decreased with increasing level Ib sparing (40.7 Gy [A] vs 35.4 Gy [B] vs 30.7 [C]; P = 0.002). The rate of late grade ≥2 xerostomia was significantly lower in patients with bilateral 1b sparing (53% in A vs 0% in C; P = 0.007). Sparing 1b unilaterally resulted in a non-significant decrease in late grade ≥2 xerostomia (P = 0.181). No regional failures were identified in levels IB (median follow up = 59.3 months).

CONCLUSION

Sparing level IB is safe in T1-2N+ HPV+ OPC. Avoiding level Ib translates into significantly lower SMG and oral cavity doses. Larger studies are needed to validate these findings and the impact of this technique.

Correlation between plan quality improvements and reduced acute dysphagia and xerostomia in the definitive treatment of oropharyngeal squamous cell carcinoma

BACKGROUND

To evaluate plan quality using volumetric-modulated arc therapy (VMAT) and step-and-shoot intensity-modulated radiation therapy (SS-IMRT) techniques and for patients treated for oropharyngeal squamous cell carcinoma (OPSCC).

METHODS

Treatment plans for patients treated definitively for stages I-IVb, OPSCC between December 2009 and August 2015 were retrospectively reviewed. Dosimetric endpoints of involved organs-at-risk (OARs) were retrieved from clinical plans. Common Terminology Criteria for Adverse Events scores of acute toxicities were compared.

RESULTS

Two-hundred twenty-two patients were identified with 134 and 88 receiving SS-IMRT and VMAT with median follow-up time of 23.0 and 7.9 months, respectively. The dosimetric endpoints of the OARs were significantly improved in VMAT cohort, which translated into significantly lower rates of grade 2 or higher acute dysphagia and xerostomia.

CONCLUSION

Improvements in stages I-IVb, oropharyngeal cancer plan quality are associated with reduced grade ≥ 2 acute dysphagia and xerostomia.

Selectively sparing the submandibular gland when level Ib lymph nodes are included in the radiation target volume: An initial safety analysis of a novel planning objective

BACKGROUND

Submandibular gland (SMG) metastases are extremely rare in head and neck cancer, even in the presence of level Ib lymph node (LN) involvement. In recent years, we have contoured the SMG and specifically attempted to limit its dose exposure even in patients in whom the level Ib LN station is targeted. This study reports our preliminary feasibility and safety experience with selective submandibular gland sparing.

METHODS

Patients with squamous cell cancer (SCC) of the oral cavity or oropharynx with T1-2, N0-3, M0 disease in whom at least a single level Ib lymph node region was included in the target volume were identified. All patients were treated from 2009 to 2014 with definitive or postoperative IMRT with or without chemotherapy. Patients with recurrent disease, previous radiation or treated palliatively were excluded.

RESULTS

A total of 174 patients met criteria for inclusion. Among the 185 level Ib LN stations that were deliberately targeted in the clinical treatment volume, 32 submandibular glands were contoured, excluded from the target volume and avoided during treatment planning. Mean dose to the spared SMG were reduced by 12% (66.6 Gy vs. 58.9 Gy, p < .001). None of these patients experienced any level 1b LN failures.

CONCLUSION

Selective sparing of the submandibular gland when targeting the level 1b nodes in oral cavity and oropharynx cancer is feasible, reduces the mean dose to submandibular glands and does not result in increased level 1b nodal failure rates. Additional studies with larger cohorts are needed to validate this preliminary observation.

Effect of Tumor Location and Dosimetric Predictors for Chest Wall Toxicity in Single-Fraction Stereotactic Body Radiation Therapy for Stage I Non-Small Cell Lung Cancer

PURPOSE

Dosimetric parameters to limit chest wall toxicity (CWT) are not well defined in single-fraction (SF) stereotactic body radiation therapy (SBRT) phase 2 trials. We sought to determine the relationship of tumor location and dosimetric parameters with CWT for SF-SBRT.

METHODS AND MATERIALS

From a prospective registry of 1462 patients, we identified patients treated with 30 Gy or 34 Gy. Gross tumor volume was measured as abutting, ≤1 cm, 1 to 2 cm, or >2 cm from the chest wall. CWT was prospectively graded according to Common Terminology Criteria for Adverse Events version 3.0, with grade 2 requiring medical therapy, grade 3 requiring procedural intervention, and grade 4 being disabling pain. Grade 1 CWT or radiographic rib fracture was not included. Logistic regression analysis was used to identify the parameters associated with CWT and calculate the probability of CWT with dose.

RESULTS

This study included 146 lesions. The median follow-up time was 23.8 months. The 5-year local control, distant metastasis, and overall survival rates were 91.8%, 19.2%, and 28.7%, respectively. Grade 2 to 4 CWT was 30.6% for lesions abutting the chest wall, 8.2% for ≤1 cm from the chest wall, 3.8% for 1 to 2 cm from the chest wall, and 5.7% for >2 cm from the chest wall. Grade ≥3 CWT was 1.4%. Tumor abutment (odds ratio [OR]: 6.5; P = .0005), body mass index (OR: 1.1; P = .02), rib D1cc (OR: 1.01/Gy; P = .03), chest wall D1cc (OR: 1.08/Gy; P = .03), and chest wall D5cc (OR: 1.10/Gy; P = .01) were significant predictors for CWT on univariate analysis. Tumor abutment was significant for CWT (OR: 7.5; P = .007) on multivariate analysis. The probability of CWT was 15% with chest wall D5cc at 27.2 Gy and rib D1cc at 30.2 Gy.

CONCLUSIONS

The rate of CWT with SF-SBRT is similar to the rates published for fractionated SBRT, with most CWT being low grade. Tumor location relative to the chest wall is not a contraindication to SF-SBRT, but the rates increase significantly with abutment. Rib D1cc and chest wall D1cc and D5cc may be used as predictors of CWT.

Suboptimal Outcomes in Cutaneous Squamous Cell Cancer of the Head and Neck with Nodal Metastases

BACKGROUND/AIM

There are limited data regarding survival, failure patterns, and factors associated with disease recurrence in patients with cutaneous squamous cell cancer of the head and neck (cSCC-HN) with nodal metastases.

PATIENTS AND METHODS

A retrospective analysis of patients with cSCC-HN metastatic to cervical and/or parotid lymph nodes treated with surgery and post-operative radiation therapy was performed.

RESULTS

This study included 76 patients (57 immunocompetent and 18 immunosuppressed) with a median follow-up of 18 months. Overall survival, disease-free survival (DFS), and disease recurrence (DR) at 2 years was 60%, 49%, and 40%, respectively. Immunosuppressed patients had significantly lower 2-year DFS (28% vs. 55%; p=0.003) and higher DR (61% vs. 34%; p=0.04) compared to immunocompetent patients. Analysis of immunocompetent patients demonstrated extracapsular extension (ECE) as the only factor associated with DR (p<0.0001).

CONCLUSION

Patients with nodal metastases from cSCC-HN have suboptimal outcomes. ECE and immunosuppression were significantly associated with DR.

Definitive Chemoradiation in Locally Advanced Squamous Cell Carcinoma of the Hypopharynx: Long-term Outcomes and Toxicity

BACKGROUND/AIM

Definitive chemoradiation (CRT) is a common approach for locally advanced hypopharyngeal squamous cell carcinoma (SCC) with the goal of organ preservation. Reports on long-term oncologic and functional outcomes have been limited. This study reports on outcomes utilizing this approach at a single institution over 30 years.

MATERIALS AND METHODS

Medical records for patients with stage III-IVB SCC of the hypopharynx were retrospectively reviewed. Patient and disease-related factors were identified and analyzed for impact on overall survival (OS), cancer-specific survival (CSS), disease-free survival, distant failure, and locoregional failure.

RESULTS

A total of 54 patients were identified who were treated with definitive CRT to a mean dose of 72 Gy. With a median follow-up period of 49.8 months, 5- and 10-year OS was 62% and 43% respectively. Five and 10-year CSS were 74% and 72% respectively. Ten-year local control was 78%. Of the 37 patients with no treatment failure, 29% experienced a grade 3 or higher late toxicity, with the majority resolving during continued long-term follow-up.

CONCLUSION

This study demonstrates good outcomes with long-term follow-up with acceptable rates of late toxicities. The findings here represent the longest published median follow-up in this population and validate the strategy of organ preservation.

Dosimetric differences between local failure and local controlled non-small cell lung cancer patients treated with stereotactic body radiotherapy: A matched-pair study

INTRODUCTION

Concerns were raised about the accuracy of pencil beam (PB) calculation and potential underdosing of medically inoperable non-small cell lung cancer (NSCLC) treated with stereotactic body radiation therapy (SBRT). From our institutional series, we designed a matched-pair study where each local failure and controlled patient was matched based upon several clinical factors, to investigate the dose difference between the matched-pair.

METHODS

Eighteen pairs of NSCLC patients, treated with 50 Gy in five fractions, were selected. These patients were matched based on treatment intent, tumour size, histology and clinical follow-up. All PB calculated clinical plans were retrospectively recalculated with a MC algorithm. The D₉₉ and D_Mean of the gross tumour volume (GTV) and D₉₅ and D_Mean of the planning tumour volume (PTV) from PB and Monte Carlo (MC) calculation were compared between local failures and controls using the Mann-Whitney test.

RESULTS

The mean PB calculated D95 of PTV was 50.4 Gy for both failures and controls (P = 0.85), indicating no planning differences between the groups. From MC calculations, the mean (±SD) of GTV D₉₉ , GTV D_Mean , PTV D₉₅ , PTV D_Mean were 47.6 ± 2.6/46.3 ± 2.4, 50.4 ± 2.1/49.8 ± 1.6, 44.4 ± 2.7/43.6 ± 3.1, 48.7 ± 2.4/48.2 ± 2.4 Gy for failure/controlled groups, respectively, and there was no significant difference between two groups (all P > 0.1). The dose differences between MC and PB calculations were in agreement with other literatures and there was no significant difference between two groups.

CONCLUSIONS

While PB algorithms may overestimate tumour doses relative to MC algorithms, our matched-pair study did not find dose differences between local failure and local controlled cases.

A matched comparison of human papillomavirus-induced squamous cancer of unknown primary with early oropharynx cancer

OBJECTIVES/HYPOTHESIS

Patients with human papillomavirus (HPV)-induced cancer of unknown primary (CUP) are generally excluded from clinical trials, despite surgical series reporting detection rates of occult oropharynx primaries of >80%. We performed a matched-pair analysis to compare outcomes between T0N1-3M0 HPV+ CUP and T1-2N1-3M0 HPV+ oropharynx known primary (OPX).

STUDY DESIGN

Retrospective cohort study at a single institution.

METHODS

Patients with early T stage, node positive HPV+ OPX or CUP treated with curative intent between 1998 and 2016 were identified. For a subgroup of CUP patients with an unknown HPV status, we imputed HPV status and included patients with a >80% probability of being HPV+. Cohorts were matched based on patient demographics using a nearest neighbor propensity technique. After matching, patients were grouped according to either a favorable or unfavorable risk stratification designations per current NRG Oncology clinical trial enrollment criteria. Disease-free survival (DFS) and overall survival (OS) were calculated using Kaplan-Meier analysis.

RESULTS

Of 298 patients with T1-2N1-3 OPX, 48 were matched to 48 HPV+ CUP patients (32 with confirmed and 16 imputed HPV status). Median follow-up for CUP (34.1 months) and OPX (27.8 months) patients were similar (P = .23).There were no significant differences between the CUP and OPX groups for 3-year DFS (89% vs. 85%, P = .44), and 3-year OS (91% vs. 91%, P = .11), respectively.

CONCLUSIONS

Patients with T0N+M0 HPV-induced CUP have similar survival outcomes to matched patients with T1-2N+M0 HPV+ OPX. These patients can reasonably be included in clinical trials investigating the role of treatment deintensification and risk stratified similar to patients with early-stage known primary OPX cancer.

LEVEL OF EVIDENCE

4. Laryngoscope, 128:1379-1385, 2018.

Tumor Control and Toxicity for Common Stereotactic Body Radiation Therapy Dose-Fractionation Regimens in Stage I Non-Small Cell Lung Cancer

PURPOSE

To examine the impact of stereotactic body radiation therapy (SBRT) dose on outcomes in early-stage non-small cell lung cancer in a large single-institution series.

METHODS AND MATERIALS

We reviewed 600 patients treated from 2003 to 2012 for early-stage non-small cell lung cancer. The SBRT dose was at physician discretion on the basis of tumor size and location. Peripheral tumors were treated to 60 Gy in 3 fractions (homogeneous planning), 48-50 Gy in 4-5 fractions, or 30-34 Gy in 1 fraction. Central tumors were treated to 50 Gy in 5 fractions, 60 Gy in 8 fractions, or 50 Gy in 10 fractions. Patient, tumor, and treatment factors were assessed for their impact on patterns of failure, toxicity, and survival.

RESULTS

An SBRT dose of 54-60 Gy in 3 fractions was associated with a statistically significant lower rate of local failure (LF) (4.3% at 2 years) compared with 30-34 Gy in 1 fraction (21%), 48-50 Gy in 4-5 fractions (15.5%), and 50-60 Gy in 8-10 fractions (13.3%). Lower pre-SBRT hemoglobin and higher positron emission tomography standardized uptake value were also associated with LF. Nodal failure, distant failure, and overall survival were similar between fractionation groups. Pulmonary toxicity (crude rate, any grade) was slightly higher for 3 fractions (5.0%) compared with 1 (3.2%) or 4-5 fractions (3.8%). Chest wall toxicity was also higher for 3 (23.7%) compared with 1 (8.6%) or 4-5 (7.7%) fraction regimens.

CONCLUSIONS

Although higher biologically equivalent dose SBRT (150-180 Gy₁₀) may be associated with slightly lower LF, it was also associated with mildly increased toxicity and no difference in other patterns of failure or overall survival.

Determinants of short and long term outcomes in patients undergoing immediate breast reconstruction following neoadjuvant chemotherapy

BACKGROUND

We evaluated oncologic outcomes and complications of skin-sparing mastectomy (SSM) and nipple-sparing mastectomy (NSM) with immediate reconstruction (IR) after neoadjuvant chemotherapy (NAC) in patients with early-stage and locally advanced breast cancer (BC).

METHODS

BC patients from 2000 to 2014 treated with NAC followed by SSM/NSM and IR were reviewed. Patient demographics, tumor characteristics, NAC response, complications, and recurrence were analyzed.

RESULTS

Two hundred sixty-nine patients with 280 BCs were treated with NAC followed by SSM (94%) or NSM (6%) with IR. Median age was 47 (26-72) years with a median follow-up of 45 months. Pathologic complete response (pCR) was noted in 49 (17.5%) cases. Overall 30-day complication rate was 13.2%. Variables associated with complications included BMI (P < 0.0001), tobacco use (P = 0.015), and adjuvant radiation (P = 0.025). Local-regional recurrence was 3.2% and metastatic recurrence was 13.2%. Variables predicting recurrence risk were pre-NAC tumor size (P < 0.001), residual tumor size (P = 0.002), Grade III (P = 0.002), HER-2 negative (P = 0.025), pre-NAC nodal disease (P = 0.05), and lack of pCR (P = 0.045).

CONCLUSION

Following NAC, risk factors for complications in patients undergoing SSM/NSM with IR are high BMI, smoking, and adjuvant XRT. SSM/NSM following NAC is associated with excellent local control. These data support expanding the indications for NSM/SSM to include patients receiving NAC.

A Histologic Basis for the Efficacy of SBRT to the lung

PURPOSE

Stereotactic body radiation therapy (SBRT) is the standard of care for medically inoperable patients with early-stage NSCLC. However, NSCLC is composed of several histological subtypes and the impact of this heterogeneity on SBRT treatments has yet to be established.

METHODS

We analyzed 740 patients with early-stage NSCLC treated definitively with SBRT from 2003 through 2015. We calculated cumulative incidence curves using the competing risk method and identified predictors of local failure using Fine and Gray regression.

RESULTS

Overall, 72 patients had a local failure, with a cumulative incidence of local failure at 3 years of 11.8%. On univariate analysis, squamous histological subtype, younger age, fewer medical comorbidities, higher body mass index, higher positron emission tomography standardized uptake value, central tumors, and lower radiation dose were associated with an increased risk for local failure. On multivariable analysis, squamous histological subtype (hazard ratio = 2.4 p = 0.008) was the strongest predictor of local failure. Patients with squamous cancers fail SBRT at a significantly higher rate than do those with adenocarcinomas or NSCLC not otherwise specified, with 3-year cumulative rates of local failure of 18.9% (95% confidence interval [CI]: 12.7-25.1), 8.7% (95% CI: 4.6-12.8), and 4.1% (95% CI: 0-9.6), respectively.

CONCLUSION

Our results demonstrate an increased rate of local failure in patients with squamous cell carcinoma. Standard approaches for radiotherapy that demonstrate efficacy for a population may not achieve optimal results for individual patients. Establishing the differential dose effect of SBRT across histological groups is likely to improve efficacy and inform ongoing and future studies that aim to expand indications for SBRT.

Carotid blowout in a patient with nasopharyngeal carcinoma treated with SBRT re-irradiation for local recurrence using twice weekly treatment

We present the case of a patient undergoing reirradiation for a T4 nasopharyngeal tumor 1 year after his initial radiation, treated with SBRT to a moderate dose with twice weekly fractionation. Despite the measures of caution employed, the patient had a fatal carotid blowout at 7 months following SBRT. This suggests that spacing apart fractions of SBRT alone may not be sufficient to obviate the risk of carotid blowout syndrome and other risk factors and interventions should be considered.

Synchronous non small cell lung cancer nodules treated with stereotactic body radiation therapy (SBRT)

BACKGROUND AND PURPOSE

We compare our institutional outcomes of synchronous primary (SP) lung lesion patients with non-SP patients.Materials and Methods: From an IRB approved prospective registry of 445 NSCLC patients treated with SBRT (8/2005 8/2012), 26 (5.8%) had SPs by biopsy or PET/CT. SBRT was delivered on a Novalis/BrainLAB platform with daily Exactrac set-up.

RESULTS

There were no significant differences comparing SP vs non-SP groups for age, Charlson score, smoking pack years, and PET SUV (p=ns). 18 (69%) SP patients had at least one lesion biopsied. Ipsilateral and bilateral SPs were seen in 10 (38.4%) and 16 (61.6%) respectively. 77% received 50 Gy / 5 fx. SP vs non-SP median follow up was 12 (range 1.5-49.8) vs 15.2 months. Median survival for SP vs non-SP groups was 20.7 vs 28.4 months (p=0.3). In SP vs non-SP groups, local failure was 4% vs 7.6% (p=ns) and nodal/distant failure was 23% vs 24.6% (p=ns). Patients with ipsilateral and bilateral SPs had a 50% vs 14% distant failure respectively (p=0.037).

CONCLUSIONS

After SBRT, there were no differences in survival and patterns of failure for SP vs non-SP patients. Ipsilateral SPs had significantly worse distant failure compared to bilateral SPs.

Organoplatinum(IV) complexes with functional alkyl groups and their use in supramolecular chemistry

The oxidative addition of alkyl bromides RCH2Br (R = C5H4N, C6H4CN, CH2C6H4CO2H, or CH2C6H4CH2CO2H) to dimethylplatinum(II) complexes [PtMe2(LL)] (LL = diimine ligand) gives the corresponding organoplatinum(IV) complexes [PtBrMe2(CH2R)(LL)] containing functionality in the alkyl group RCH2. The pyridyl derivatives can be protonated, while abstraction of the bromide ligand from [PtBrMe2(CH2R)(LL)] can form cationic complexes, which can react with water or form oligomers by self-assembly.