Breast Reconstruction Complications After Postmastectomy Proton Radiation Therapy for Breast Cancer.

Purpose: Our purpose was to report complications requiring surgical intervention among patients treated with postmastectomy proton radiation therapy (PMPRT) for breast cancer in the setting of breast reconstruction (BR). Methods and Materials: Patients enrolled on a prospective proton registry who underwent BR with immediate autologous flap, tissue expander (TE), or implant in place during PMPRT (50/50.4 Gy +/- chest wall boost) were eligible. Major reconstruction complication (MRC) was defined as a complication requiring surgical intervention. Absolute reconstruction failure was an MRC requiring surgical removal of BR. A routine revision (RR) was a plastic surgery refining cosmesis of the BR. Kaplan-Meier method was used to assess disease outcomes and MRC. Cox regression was used to assess predictors of MRC. Results: Seventy-three courses of PMPRT were delivered to 68 women with BR between 2013 and 2021. Median follow-up was 42.1 months. Median age was 47 years. Fifty-six (76.7%) courses used pencil beam scanning PMPRT. Of 73 BR, 29 were flaps (39.7%), 30 implants (41.1%), and 14 TE (19.2%) at time of irradiation. There were 20 (27.4%) RR. There were 9 (12.3%) MRC among 5 implants, 2 flaps, and 2 TE, occurring a median of 29 months from PMPRT start. Three-year freedom from MRC was 86.9%. Three (4.1%) of the MRC were absolute reconstruction failure. Complications leading to MRC included capsular contracture in 5, fat necrosis in 2, and infection in 2. On univariable analysis, BR type, boost, proton technique, age, and smoking status were not associated with MRC, whereas higher body mass index trended toward significance (hazard ratio, 1.07; 95% CI, 0.99-1.16; P = .10). Conclusions: Patients undergoing PMPRT to BR had a 12.3% incidence of major complications leading to surgical intervention, and total loss of BR was rare. MRC rates were similar among reconstruction types. Minor surgery for RR is common in our practice.

Hippocampus sparing volumetric modulated arc therapy in patients with loco-regionally advanced oropharyngeal cancer.

This study aimed to assess the incidental radiation exposure of the hippocampus (HC) in locoregionally-advanced oropharyngeal cancer patients undergoing volumetric modulated arc therapy and the feasibility of HC-sparing plan optimization. The initial plans were generated without dose-volume constraints to the HC and were compared with the HC-sparing plans. The incidental Dmean_median doses to the bilateral, ipsilateral and contralateral HC were 2.9, 3.1, and 2.5 Gy in the initial plans and 1.4, 1.6, and 1.3 Gy with HC-sparing. It was feasible to reduce the HC dose with HC-sparing plan optimization without compromising target coverage and/or dose constraints to other OARs.

Feasibility of optimizing intensity-modulated radiation therapy plans based on measured mucosal dose adjacent to dental fillings and toxicity outcomes.

We prospectively investigated the feasibility of IMRT treatment plan optimization based on dosimeter measurements of lateral tongue mucosal dose adjacent to the dental fillings and evaluated dose-toxicity relationship and factors affecting oral mucositis (OM) in head and neck cancer patients. Twenty-nine head and neck cancer patients with metallic dental fillings who were scheduled to undergo fractionated external beam radiation therapy (RT) ± chemotherapy were enrolled. The lateral tongue dose was measured and if the calculated dose for the entire treatment was ≥35 Gy, a re-plan was generated to reduce the lateral tongue mucosal dose. OM was graded weekly according to Common Terminology Criteria for Adverse Events version 4.0 and the patients completed the Oral Mucositis Weekly Questionnaire-Head and Neck Cancer. The result showed that it was not feasible to optimize the IMRT plan based on measured tongue dose in most of the patients who needed re-plan as re-planning compromised the target coverage in 60% of these patients. The duration of grade (Gr) 2 OM was correlated with measured lateral tongue dose (P = 0.050). Concurrent cetuximab was significantly associated with faster onset of Gr2 OM than concurrent cisplatin (P = 0.006) and with longer duration of OM (P = 0.041) compared to concurrent cisplatin or IMRT-alone. The pattern of reported pain over time was significantly different for each treatment type (RT and cetuximab, RT and cisplatin and RT-alone) and depending on the dose level (P = 0.006). In conclusion, optimizing the IMRT plan based on measured lateral tongue dose was not feasible. Measured lateral tongue dose was significantly correlated with longer duration of OM ≥Gr2, and concurrent cetuximab was associated with earlier onset and longer duration of OM ≥Gr2.

Potential Role of Adjuvant Radiation Therapy in Cervical Thymic Neoplasm Involving Thyroid Gland or Neck.

PURPOSE: The purpose of this study is to assess the clinicopathologic features, treatment outcomes, and role of adjuvant radiation therapy (RT) in cervical thymic neoplasm involving the thyroid gland or neck. MATERIALS AND METHODS: The medical and pathologic records of eight patients with cervical thymic neoplasm were reviewed retrospectively. All patients underwent surgical resection, including thyroidectomy or mass excision. Adjuvant RT was added in five patients with adverse clinicopathologic features. The radiation doses ranged from 54 Gy/27 fractions to 66 Gy/30 fractions delivered to the primary tumor bed and pathologically involved regional lymphatics using a 3-dimensional conformal technique. RESULTS: Eight cases of cervical thymic neoplasm included three patients with carcinoma showing thymus-like differentiation (CASTLE) and five with ectopic cervical thymoma. The histologic subtypes of ectopic cervical thymoma patients were World Health Organization (WHO) type B3 thymoma in one, WHO type B1 thymoma in two, WHO type AB thymoma in one, and metaplastic thymoma in one, respectively. The median age was 57 years (range, 40 to 76 years). Five patients received adjuvant RT: three with CASTLE; one with WHO type B3; and one with WHO type AB with local invasiveness. After a median follow-up period of 49 months (range, 11 to 203 months), no recurrence had been observed, regardless of adjuvant RT. CONCLUSION: Adjuvant RT after surgical resection might be worthwhile in patients with CASTLE and ectopic cervical thymoma with WHO type B2-C and/or extraparenchymal extension, as similarly indicated for primary thymic epithelial tumors. A longer follow-up period may be needed in order to validate this strategy.

Treatment outcome of hepatic re-irradiation in patients with hepatocellular carcinoma.

PURPOSE: We evaluated the efficacy and toxicity of repeated high dose 3-dimensional conformal radiation therapy (3D-CRT) for patients with unresectable hepatocellular carcinoma. MATERIALS AND METHODS: Between 1998 and 2011, 45 patients received hepatic re-irradiation with high dose 3D-CRT in Samsung Medical Center. After excluding two ineligible patients, 43 patients were retrospectively reviewed. RT was delivered with palliative or salvage intent, and equivalent dose of 2 Gy fractions for α/ß = 10 Gy ranged from 31.25 Gy10 to 93.75 Gy10 (median, 44 Gy10). Tumor response and toxicity were evaluated based on the modified Response Evaluation Criteria in Solid Tumors criteria and the Common Terminology Criteria for Adverse Events (CTCAE) ver. 4.0. RESULTS: The median follow-up duration was 11.2 months (range, 4.1 to 58.3 months). An objective tumor response rate was 62.8%. The tumor response rates were 81.0% and 45.5% in patients receiving ≥45 Gy10 and <45 Gy10, respectively (p = 0.016). The median overall survival (OS) of all patients was 11.2 months. The OS was significantly affected by the Child-Pugh class as 14.2 months vs. 6.1 months (Child-Pugh A vs. B, p < 0.001), and modified Union for International Cancer Control (UICC) T stage as 15.6 months vs. 8.3 months (T1-3 vs. T4, p = 0.004), respectively. Grade III toxicities were developed in two patients, both of whom received ≥50 Gy10. CONCLUSION: Hepatic re-irradiation may be an effective and tolerable treatment for patients who are not eligible for further local treatment modalities, especially in patients with Child-Pugh A and T1-3.

Comparison of acute skin reaction following morning versus late afternoon radiotherapy in patients with breast cancer who have undergone curative surgical resection.

We investigated the relationship between the time of radiotherapy (RT) and treatment outcomes in breast cancer. Patients with pathologic T1-2N0-1 breast cancer who received adjuvant RT in the morning (before 10:00 AM) or late afternoon (after 3:00 PM) were eligible for inclusion in this study. We retrospectively compared the clinicopathologic characteristics, acute skin reaction, and survival outcomes according to the time of RT. The median follow-up duration was 83 months (range, 10-131 months). From the 395 eligible patients, 190 (48.1%) and 205 (51.9%) patients were classified into the morning RT group and the afternoon RT group, respectively. The clinicopathologic characteristics were relatively well balanced between the treatment groups, except for pathologic N-stage (P = 0.0409). Grade 2 or higher acute skin reaction according to the Radiation Therapy Oncology Group criteria was observed in 39 (9.9%) patients, with a higher frequency in the afternoon RT group than the morning RT group (13.7% vs 5.8%, respectively; P = 0.0088). There was no difference in the failure patterns or survival outcomes between the treatment groups. RT in late afternoon was associated with increased Grade 2 or more skin reaction after RT for breast cancer patients, but treatment outcomes did not differ according to the time of RT. Individualized considerations for treatment should be taken into account to reduce the risk of skin reactions.