Consent document translation expense hinders inclusive clinical trial enrolment

Patients from historically under-represented racial and ethnic groups are enrolled in cancer clinical trials at disproportionately low rates in the USA1-3. As these patients often have limited English proficiency4-7, we hypothesized that one barrier to their inclusion is the cost to investigators of translating consent documents. To test this hypothesis, we evaluated more than 12,000 consent events at a large cancer centre and assessed whether patients requiring translated consent documents would sign consent documents less frequently in studies lacking industry sponsorship (for which the principal investigator pays the translation costs) than for industry-sponsored studies (for which the translation costs are covered by the sponsor). Here we show that the proportion of consent events for patients with limited English proficiency in studies not sponsored by industry was approximately half of that seen in industry-sponsored studies. We also show that among those signing consent documents, the proportion of consent documents translated into the patient's primary language in studies without industry sponsorship was approximately half of that seen in industry-sponsored studies. The results suggest that the cost of consent document translation in trials not sponsored by industry could be a potentially modifiable barrier to the inclusion of patients with limited English proficiency.

Is There a Place for Temozolomide plus Nivolumab among Neuroendocrine Neoplasms?

Immune checkpoint inhibitors have revolutionized the treatment of multiple solid malignancies, but their role in the treatment of neuroendocrine neoplasms (NEN) is unclear. The accompanying article reports on a study combining the programmed cell death (PD-1) inhibitor nivolumab with the alkylating agent temozolomide in patients with advanced NENs. See related article by Owen et al., p. 731.

Primary analysis from the phase 2 study of continuous talazoparib (TALA) plus intermittent low-dose temozolomide (TMZ) in patients with relapsed or refractory extensive-stage small cell lung cancer (ES-SCLC)

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Background: TALA exhibits cytotoxic effects by inhibiting poly (ADP-ribose) polymerase (PARP) proteins 1 and 2 in addition to “trapping” PARP on DNA. TMZ has been shown to increase antitumor response when combined with TALA in SCLC models (Wainberg AACR 2016). TALA plus TMZ as second-line therapy for ES-SCLC may improve disease-related outcomes. Methods: This is a phase 2, open-label, single-arm study of the safety and efficacy of TALA plus TMZ in patients with ES-SCLC, relapsed or refractory to a first-line platinum-based regimen. Participants receive TALA 0.75 mg (or 0.5 mg if creatinine clearance < 60 mL/min) po daily on 28-day cycles with TMZ 37.5 mg/m2 po on days 1-5. The primary endpoint is objective response rate (ORR) based on RECIST 1.1 criteria, versus a historical control of 15% ORR in second-line topotecan, with the null hypothesis rejected for 8 or more confirmed responses among 28 evaluable subjects (29% ORR). Secondary endpoints include progression-free survival, overall survival, duration of response, and time to response. Exploratory endpoints include biomarker studies such as status of DNA damage response genes (DDR) and patient reported outcomes. A Simon two-stage design was utilized to reach a total accrual of 28 evaluable patients. Results: Thirty-one subjects were enrolled, of which 3 were non-evaluable due to ineligibility (1) or early withdrawal of consent prior to first disease assessment (2). Eleven of 28 evaluable subjects (39.3%) achieved a confirmed partial response. The ORR was similar among platinum-refractory (3/6), -resistant (4/9), and -sensitive subgroups (4/13). The median time to response was 1.8 months (m), duration of response 5.8 m, progression free survival 4.5 m, and overall survival 11.9 m. Adverse events (AEs) were manageable, with grade ≥ 3 AEs being thrombocytopenia (61.3%), anemia (54.8%), neutropenia (41.9%), and atypical pneumonia (3.2%), which responded well to dose-hold or dose-reduction and transfusion or growth factor support as needed. Cell free DNA and tissue analysis demonstrated no germline DDR mutations among the trial subjects, but somatic DDR mutations at baseline and acquired during treatment were common. Three subjects remain on study treatment. Conclusions: The study exceeded its target response rate. This is the second trial to demonstrate a benefit of PARP inhibition with low-dose TMZ in SCLC (see Farago Cancer Discovery 2019). A phase 3 study is appropriate to confirm the benefit of this approach compared to currently approved options. Clinical trial information: NCT03672773.

Circulating tumor DNA (ctDNA) mutations associate with response in patients (pts) with extensive-stage small cell lung cancer (ES-SCLC) treated with talazoparib (TALA) and temozolomide (TMZ)

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Background: Poly (ADP-ribose) polymerase (PARP) inhibition in combination with TMZ is a promising treatment strategy for ES-SCLC. In SCLC models, TALA, a potent PARP inhibitor, exhibits cytotoxic effects by impairing PARP proteins 1/2 and trapping PARP on DNA while TMZ potentiates antitumor response by contributing to genomic instability (Wainberg 2016). A prior analysis of ctDNA in 15 pts treated on trial with TALA and TMZ suggested that mutations in DNA damage repair (DDR) genes occurred with this combination and may associate with response (Mulroy ASCO 2021). Methods: Pts with relapsed or refractory ES-SCLC were treated with TALA 0.75 mg po daily with TMZ 37.5 mg/m2 po on days 1-5 of 28-day cycles in a phase 2 clinical trial (UCLA/TRIO-US L-07, NCT03672773). ctDNA was collected and assessed based on allele frequency and plasma copy number at baseline and every 8 weeks during treatment with the Guardant360 assay (Redwood City, CA). DDR status was defined as a mutation known or likely to result in aberrant expression of ATM or BRCA1/2 (other DDR genes not detected by assay) (Pearl 2015). Germline DDR mutations were evaluated with matched-normal (PBMC) whole exome sequencing (WES) with archival specimens by Tempus (Chicago, IL). Response to treatment was defined by RECIST 1.1 criteria. Fisher’s exact tests were used to compare proportions of patients, with P-values <0.05 considered statistically significant ( www.r-project.org , Vienna, AU). Results: For 27 pts with evaluable response, 78 ctDNA samples were collected. The most common baseline somatic alterations were mutations in TP53 (23 pts), RB1 (8 pts), ATM (5 pts), and BRCA2 (5 pts). There were no patients with germline DDR mutations. Overall, 22/27 (81.5%) had disease control (DC), including 11 with confirmed partial responses (PR) and 11 with stable disease while 5 had progressive disease. All those with PRs and ctDNA burden >0.2% at baseline experienced a ctDNA decrease at 8 weeks of treatment. DDR mutations were found in 18/27 (66.7%) pts. Of those with ≥ 1 follow-up ctDNA time point collected, 13/17 (76.4%) pts had at least one new mutation detected while on treatment, most commonly in ATM (6 pts). The appearance of new mutations associated with DC (P=0.042) and with a trend towards improved progression free survival (PFS, 5.9 m vs 3.6 m, P=0.099). All 5 pts with DDR mutations present at baseline had DC with TALA and TMZ, and 9/11 (81.8%) of those with PR had DDR mutations detected at some point during the trial, although the trend toward DC enrichment with DDR mutations did not maintain statistical significance (P=0.24). Conclusions: Mutations in DDR genes occur on treatment with TALA and TMZ and may associate with disease control. Validation in a larger cohort will be pursued.

Cost of consent document (CD) translation is a potential barrier to consenting limited English-proficient participants (LEPPs) in non-industry–sponsored studies (NISS)

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Background: Racial/ethnic minority patients (pts) are underrepresented in cancer clinical trials. Challenges specific to LEPPs include the need for translated CDs, which can cause research delays and add cost. While most enrollment barriers are similar between industry sponsored studies (ISS) and NISS, costs of CD translation are typically covered by the sponsor in ISS. NISS often have limited, or no funds allocated for CD translation. Although it is required that LEPPs sign translated CDs, we hypothesized that investigators on NISS would find ways to avoid incurring the cost of CD translation. Methods: All pts who consented to studies at the UCLA Jonsson Comprehensive Cancer Center from 2013-2018 were included. Electronic health record data was reviewed. Adult LEPPs had a primary language other than English and their chart either flagged them as needing an interpreter or the pt used an interpreter in their care 6 months before or after the consent date. For pediatric patients, regardless of the pt’s primary language, LEPPs had a guardian who needed an interpreter within 6 months of the consent date. CD language was documented when available by chart review, but when not, we evaluated all IRB-approved CDs for the corresponding study and assumed that the pt signed appropriately translated CDs if available at the time of consent or within the following month. Chi square tests were used to compare the proportion of LEPPs who consented to NISS vs ISS and the proportion of LEPPs who consented with CDs not in their primary language. All analyses were performed using JMP, Version 16. SAS Institute Inc., Cary, NC, 1989–2021. Results: Although we do not have access to data on to whom consents were offered, of the 12202 consenting events during the study period, the proportion of consenting events for LEPPs was 2.7% in NISS vs 5.4% for ISS (p < 0.01). This difference did not appear to be driven by study type, as results were similar when only consenting events for interventional studies (n = 9886) were considered, with LEPPs representing 2.4% in NISS vs 5.5% in ISS (p < 0.01). Among LEPPs, 67.2% of participants who consented to NISS consented with CDs in a language other than their primary language vs 32.2% in ISS (p < 0.01). LEPPs who consented with language appropriate CDs represented 0.9% of those consenting to NISS vs 3.7% for ISS (p < 0.01). Conclusions: LEPPs consented less frequently to NISS compared to ISS, and when they did consent to NISS, the CDs were usually not translated into the pt’s primary language. We posit that the cost of translating CD discourages investigators from consenting LEPPs to NISS. Approaches that reduce or eliminate translation costs should increase the availability of translated CDs, potentially increasing enrollment of LEPPs to NISS while ensuring that they are fully informed about the purpose, procedures, and risks involved in these trials.

Immune checkpoint inhibitor induced thyroid dysfunction is a frequent event post-treatment in NSCLC

INTRODUCTION

Thyroid dysfunction is the most frequent endocrine immune related adverse event (irAE) in non-small cell lung cancer (NSCLC), typically arising 3-6 months into immune checkpoint inhibitor (ICI) therapy, but arising after ICI cessation, in some cases. Due to limited post-treatment adverse event reporting requirements on ICI trials, the incidence of ICI-induced thyroid dysfunction arising after therapy is unclear. We investigated ICI-induced thyroid dysfunction in a cohort of 294 NSCLC patients, with a specific focus on the post-treatment setting.

METHODS

Retrospective analysis of ICI-induced thyroid dysfunction (clinically acted upon or laboratory only) was performed in 294 UCLA NSCLC patients treated 2012-2018. Clinically acted upon thyroid dysfunction was defined as thyroid diagnosis documentation and/or thyroid medication administration. Laboratory only dysfunction was defined as abnormal thyroid labs in the absence of clinical action. Timing of thyroid dysfunction relative to ICI treatment and thyroid monitoring patterns were also assessed.

RESULTS

82% (241/294) of ICI treated NSCLC patients had thyroid labs during treatment. Of these 241 patients, 13% (31/241) had clinically acted upon thyroid dysfunction prior to, 8% (18/241) during, and 4% (9/241) after ICI. Most patients, 66% (159/241), did not have thyroid labs after ICI, but in the 53 patients with labs and no prior clinical dysfunction, 17% (9/53) developed clinical dysfunction after ICI. In these 9 patients, median time from ICI initiation to dysfunction was 253 days. Two patients with post-treatment laboratory only dysfunction were observed.

CONCLUSIONS

ICI-induced thyroid dysfunction arising post-treatment appears more common than previously appreciated, warranting additional evaluation.

Abstract 2218: MET alterations are enriched in lung adenocarcinoma brain metastases and define a distinct molecular and transcriptomic subtype

Lung cancer has the highest incidence of metastases to the brain, with up to 40% of non-small cell lung cancer (NSCLC) patients developing brain metastases (BM). There is a critical need to develop novel treatments to effectively prevent and treat NSCLC BM. MET is a receptor tyrosine kinase that upon binding hepatocyte growth factor (HGF), mediates proliferation, epithelial-mesenchymal transition (EMT), invasion, angiogenesis and metastasis. Recent studies have suggested that the MET pathway may be a significant determinant of metastatic potential to the brain. We evaluated 125 lung adenocarcinoma (LUAD) BM and 477 primary LUAD for MET amplification (amp) by FISH (MET/CEP &gt; 2) as well as other molecular alterations using targeted next-generation sequencing in a subset of LUAD BM (N=74) and primary LUAD (N=171) samples, including 13 paired primary and brain sets. We identified a significant enrichment of MET amp in LUAD BM (19%) compared to primary LUAD (3%; p&lt;0.00001) or liver metastases (4%, N=80; p=0.002). High MET amp (MET/CEP7 ratio &gt;5) was present in 6.5% of BM compared to 1.3% of primary LUAD cases (p=0.0006). In matched samples, BM-specific MET amp was observed. Non-exon 14 skipping MET activating mutations were also significantly more frequent in LUAD BM (22%) compared to primary LUAD (12%; p=0.05), as well as TP53, KRAS, SMAD4, APC, RB1, RET, ABL1, ALK, and VHL variants (adj. p values &lt;0.02). VHL and IDH1 mutations were significantly increased in MET altered compared to non-MET altered BM. In addition, KRAS Q61X variants were more common in LUAD BM compared to LUAD and specifically more common in MET amp BM. We also examined MET activation in paired tumors using an HGF-MET proximity binding, dual-antibody assay. MET expression was increased in the majority of BM compared to the paired LUAD, and there were brain-specific MET activation was observed. RNASeq analysis identified distinct gene signatures in MET amplified (N=11) versus non-MET amplified (N=24) LUAD BM, including upregulation of the EMT and glycolytic pathways. We validated the importance of the EMT transcription factor, TWIST1 in MET-driven NSCLC tumorigenesis preclinically and confirmed activation of the glycolytic pathway in MET amplified NSCLC. Finally, non-invasive strategies to detect brain-specific MET alterations will be needed to identify BM patients who can benefit from MET inhibitors. Therefore, we examined 277 metastatic NSCLC patients that underwent standard of care circulating tumor DNA testing with the Guardant360 platform, and found that both MET mutation and/or amp were more frequently detected in LUAD patients with BM (p=0.04). Together, we show that over a third of LUAD BM patients have MET alterations compared to primary LUAD and may be responsive to MET inhibitors. Further, our liquid biopsy approach may allow us to identify BM-specific alterations for patient selection in clinical trials.

Citation Format: Timothy F. Burns, Sanja Dacic, Maria A. Velez, Ashwin Somasundaram, Saveri Bhattacharya, Anish Chakka, Zachary A. Yochum, Jingxiao Jin, Ethan Miller, Brenda F. Kurland, Riyue Bao, Danielle P. Normolle, Sameer Agnihotri, Uma R. Chandran, Laura P. Stabile. MET alterations are enriched in lung adenocarcinoma brain metastases and define a distinct molecular and transcriptomic subtype [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2218.

Evaluation of radiomics as a predictor of tumor hypoxia and response to anti-PD-1 mab treatment (IO) in recurrent/metastatic HNSCC patients (R/M)

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Background: There is a great need for non-invasive predictors of the tumor microenvironment and the efficacy of anti-PD-1 mAb treatment (IO) in R/M HNSCC patients. We previously showed that lower tumor hypoxia was associated with increased efficacy with IO ( Journal of Clinical Oncol. 38, no. 15_suppl (May 20, 2020) 6546) and now we evaluate the predictive value of radiomics in this same patient cohort. Methods: We studied radiomic signatures in a cohort of 36 patients with R/M HNSCC treated with IO. Treatment response was evaluated using RECIST 1.1. Patients were categorized as: Responders (R) ie CR, PR, SD and non-Responders (NR) i.e PD. As per our previous analysis (ref above) hypoxia was evaluated on archival FFPE samples via immunofluorescent imaging and defined by the ratio of percent area (% CAIX) / the mean intensity (Int) of carbonic anhydrase IX in tumor (%CAIX/Int). ImageJ software was used to determine %CAIX and Int. Feature extraction was performed on the pre-immunotherapy baseline CT scans. The lesions were segmented using 3D slicer v4.10.2 to create a volume of interest (VOI) for radiomic texture analysis (TA). A total of 400 features (10 histogram-based and 390 second-order texture features) were calculated from each extracted volume of interest (VOI). Radiomic features were obtained using a feature selection approach based on Least Absolute Shrinkage and Selection Operator (LASSO). Selected features were used to build a classification model, using XGboost, for prediction of tumor response to immunotherapy. Cross-validation was performed using the Leave One Out Cross Validation (LOOCV) approach for the XGBoost method to evaluate the robustness of the estimates and calculated accuracy, sensitivity, specificity and p-value. Results: Our patient cohort had a median age of 59, 69% male, 58% smokers. 61% received IO for platinum failure, 39% frontline. Primary site included 39% OC, 22% OPC (38% HPV positive), 17% Larynx, 5% hypopharynx, and 17% other. Radiomics applied to the primary HNSCC tumor highly predicted tumor hypoxia status with a sensitivity, specificity, and accuracy of 78%, 83%, and 81%, respectively, p = 0.0001. To predict response, we applied radiomics to both the primary HNSCC tumor and pathological lymph nodes; radiomics was also able to predict whether a patient would be a responder (N = 8) versus a non-responder (N = 28) to IO based on the pre-immunotherapy baseline CT scan. The sensitivity, specificity, and accuracy were 93%, 88%, and 92%, respectively, p = 0.02. Conclusions: Even in a small cohort, radiomics could predict response to IO and tumor hypoxia in R/M HNSCC patients. To our knowledge this is the first evaluation of this kind in this patient population. Further evaluation of radiomics as a predictor of efficacy with IO and the tumor microenvironment is warranted.

The impact of tumor hypoxia on the clinical efficacy of anti-PD-1 mAb treatment in recurrent/metastatic HNSCC patients (R/M)

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Background: Anti-PD-1 mAbs have changed the landscape of R/M HNSCC treatment, but physical, immunologic, and metabolic barriers present in the tumor microenvironment are likely drivers of low response rates. Hypoxia is a well-established feature of the tumor microenvironment and may act as a barrier to T cell infiltration and function. We evaluated the effect of hypoxia on the efficacy of anti-PD-1 mAb treatment in R/M HNSCC patients. Methods: We conducted a retrospective analysis of R/M patients treated with anti-PD-1 mAb that had consented to the UPMC Hillman tissue banking protocol (HCC 99-069). Pre-treatment archival FFPE samples were analyzed via immunofluorescent imaging for number of CD8+ T cells (CD8), Tregs, and the percent area (% CAIX) and mean intensity (Int) of carbonic anhydrase IX, a well-described marker of hypoxia. Tissue sections stained with PanCK, CAIX, CD8, Foxp3, and DAPI were imaged with an Olympus IX 83 microscope. ImageJ software and custom software plugins were used to determine %CAIX, Int, CD8, and Treg. PD-L1 by IHC was reported as a combined positive score (CPS) defining positive as CPS > 1. We compared non-responders (NR) i.e. PD to responders (R) i.e. PR or SD, and analyzed OS, PFS. All data were analyzed using GraphPad Prism software. Two-tailed unpaired t test was used when comparing 2 groups, 1-way ANOVA was used for multiple comparisons, and log-rank test was used for survival analysis. Results: The 36 patients included were 69% male, median age 59, 58% smokers. 61% were platinum failure. Primary site included 39% OC, 22% OPC (38% HPV positive), 17% Larynx, 17% other, 5% hypopharynx. Low %CAIX/Int, high CD8, and high CD8/Treg were all significantly associated with R. Patients with low %CAIX/Int (12 month OS Low: 75% vs. Mid: 17% vs. High:8%, p = 0.02) and high CD8/Treg had a significant increase in OS. Only high CD8 was associated with significantly higher PFS. Low %CAIX alone showed a non-significant trend towards increased R and no difference in PFS/OS. There was no difference in CD8, CD8/Treg, PD-L1 and Treg between %CAIX/Int groups. Conclusions: To our knowledge this is the first evaluation of tumor hypoxia as a predictive biomarker in anti-PD-1 mAb treated R/M HNSCC patients. Lower hypoxia by %CAIX/Int was associated with significantly increased response and OS. While further analysis in a larger dataset is needed to confirm, the lack of significant difference in CD8, Treg, PD-L1, and CD8/Treg between %CAIX/Int groups (Low, Mid, High) suggests that hypoxia may be an independent predictive marker.

The estrogen pathway as a modulator of response to immunotherapy

Lung cancer is the leading cause of cancer deaths worldwide, with a 5-year survival rate of about 18%. Thus, there is a great need for novel therapeutic approaches to treat non-small-cell lung cancer (NSCLC). Immune checkpoint inhibitors (ICIs) have improved outcomes for a subset of patients, especially those with high programmed death-ligand 1 expression and/or high tumor mutational burden, but have failed in the majority of patients. Increasing evidence suggests that the estrogen signaling pathway may be a therapeutic target in metastatic NSCLC and that the estrogen pathway may play a role in sex-based responses to ICIs. This report will review the epidemiologic, preclinical and clinical data on the estrogen pathway in NSCLC, its implications in sex-based responses to ICIs and the potential use of antiestrogen therapy in combination with ICIs.

The HGF-MET signaling pathway is enriched in LUAC brain metastases

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Background: Brain metastases occur in over 40% of non-small cell lung cancer (NSCLC) patients leading to a poor prognosis. c-Met (MET) is a receptor tyrosine kinase that upon binding hepatocyte growth factor (HGF), mediates proliferation, epithelial-mesenchymal transition (EMT), invasion, angiogenesis and metastasis. We have previously shown that the EMT transcription factor, TWIST1 is required for proliferation in MET driven NSCLC. Therefore, the HGF/MET/TWIST1 pathway may be a significant determinant of metastatic potential to the brain. Methods: We evaluated 125 lung adenocarcinoma (LUAC) brain metastases for MET amplification by FISH as well as other molecular alterations using targeted next generation sequencing in a subset of brain metastases (N = 74) and primary LUAC (N = 171) samples including 13 paired primary and brain sets. MET activation was examined in paired tumors using a HGF-MET proximity binding, dual-antibody assay (VeraTag; Monogram Biosciences). TWIST1 and EMT markers in the paired sets were measured by immunohistochemistry. Results: Compared to primary LUAC, we found that 17 pathogenic variants including TP53, SMAD4, RB1, RET, APC, ALK, FGFR3, EGFR, STK11 and MET alterations were significantly more common in LUAC brain metastases (adj. p values ≤ 0.02). Specifically, MET amplification was significantly enriched in LUAC brain metastases (23/125, 19%) compared to 2-4% in non-brain metastatic and primary sites. Among paired samples, 2/13 brain metastases had MET amplification that was not found in the primary tumor. MET mutations were also present in 16/74 brain cases (22%) compared to 9% (16/171) observed in the lung. VHL mutations were associated with MET altered cases compared to non- MET altered cases. MET expression was increased in the majority of brain metastases compared to the paired LUAC and there were 3 cases with brain specific MET activation. We found that TWIST1 was induced by HGF and determined response to MET TKIs in vitro. Among paired samples, TWIST1 was increased in brain metastases compared to primary LUAC in a subset of cases. Further analyses of TWIST1 and EMT markers is ongoing. Conclusions: Over a third of brain metastases have MET alterations compared to primary LUAC and may be responsive to MET inhibitors.

Immunologic mediators of outcome for irradiated oropharyngeal carcinoma based on human papillomavirus status

PURPOSE

To investigate the prognostic value of pre-treatment immune parameters including white blood cell count (WBC) and circulating lymphocyte count (CLC) among patients with oropharyngeal carcinoma treated by radiation therapy.

METHODS AND MATERIALS

A total of 136 consecutive patients were treated by radiation therapy for locally advanced (stage III/IV) squamous cell carcinoma of the oropharynx with known human papillomavirus (HPV) status. Medical records were reviewed to identify patients with documented pre-treatment laboratory bloodwork. The Kaplan-Meier method and linear regression models were used to evaluate the association between pre-treatment CBC and CLC values with survival endpoints.

RESULTS

One hundred and eleven patients satisfied inclusion criteria. Median age was 62 years (range, 22-91). Eighty-four patients were HPV-positive (76%) and 27 (24%) were HPV-negative. There was no difference in WBC and CLC mean values at baseline between HPV-positive and HV-negative (p > 0.05, for both). Trends were detected in the HPV-positive cohort favoring patients with higher CLC, with respect to 2-year local-regional control (93% vs. 82%, p = 0.06) and distant control (88% vs. 82%, p = 0.10) using the median CLC as cut-off. HPV-positive patients with CLC values in the lowest quartile had inferior local-regional control compared to those in the upper 3 quartiles (69% vs. 89%, p = 0.01).

CONCLUSION

Low pre-treatment CLC was correlated with local-regional recurrence and distant failure among HPV-positive patients. These associations were not observed in the HPV-negative cohort.

Prognostic significance of HPV status in the re-irradiation of recurrent and second primary cancers of the head and neck

PURPOSE

To evaluate the prognostic significance of human papillomavirus (HPV) status among patients treated by salvage radiation therapy for local-regional recurrences and second primary cancers of the head and neck arising in a previously irradiated field.

METHODS AND MATERIALS

The medical records of 54 consecutive patients who underwent re-irradiation for squamous cell carcinoma of the head and neck occurring in a previously irradiated field were reviewed. Only patients with biopsy-proven evidence of recurrent disease that had previously been treated with doses of radiation therapy of at least 60 Gy were included. Determination of HPV status at the time of recurrence was performed by p16 immunohistochemistry. The median age at re-irradiation was 58.5 years (range, 27.9 to 81.5 years). Thirty patients (55.5%) were lifelong never-smokers. The Kaplan Meier method was used to calculate overall survival, progression-free survival, and local-regional control, and distant metastasis-free survival with comparisons between groups performed using the log-rank test.

RESULTS

HPV status among tumors that were re-irradiated was as follows: 16 positive (29.7%); 7 negative (12.9%); 31 unknown (57.4%). The median overall survival in the entire cohort was 11.7 months (range, 8 to 27 months), with the 1-year and 2-year estimates of overall survival being 47.2% and 38.4%, respectively. A statistical trend was identified favoring patients with HPV-positive cancers with respect to the endpoints of overall survival (p = 0.06) and progression-free survival (p = 0.08) after re-irradiation when compared to the HPV-negative/unknown population. There was no significant difference in distant control between the two cohorts (p = 0.40).

CONCLUSIONS

The favorable prognostic significance of HPV seemingly extends to patients treated by re-irradiation suggesting that this biomarker may be useful in risk stratification in this setting.

Tolerance of the Brachial Plexus to High-Dose Reirradiation

PURPOSE

To study the tolerance of the brachial plexus to high doses of radiation exceeding historically accepted limits by analyzing human subjects treated with reirradiation for recurrent tumors of the head and neck.

METHODS AND MATERIALS

Data from 43 patients who were confirmed to have received overlapping dose to the brachial plexus after review of radiation treatment plans from the initial and reirradiation courses were used to model the tolerance of this normal tissue structure. A standardized instrument for symptoms of neuropathy believed to be related to brachial plexus injury was utilized to screen for toxicity. Cumulative dose was calculated by fusing the initial dose distributions onto the reirradiation plan, thereby creating a composite plan via deformable image registration. The median elapsed time from the initial course of radiation therapy to reirradiation was 24 months (range, 3-144 months).

RESULTS

The dominant complaints among patients with symptoms were ipsilateral pain (54%), numbness/tingling (31%), and motor weakness and/or difficulty with manual dexterity (15%). The cumulative maximum dose (Dmax) received by the brachial plexus ranged from 60.5 Gy to 150.1 Gy (median, 95.0 Gy). The cumulative mean (Dmean) dose ranged from 20.2 Gy to 111.5 Gy (median, 63.8 Gy). The 1-year freedom from brachial plexus-related neuropathy was 67% and 86% for subjects with a cumulative Dmax greater than and less than 95.0 Gy, respectively (P=.05). The 1-year complication-free rate was 66% and 87%, for those reirradiated within and after 2 years from the initial course, respectively (P=.06).

CONCLUSION

The development of brachial plexus-related symptoms was less than expected owing to repair kinetics and to the relatively short survival of the subject population. Time-dose factors were demonstrated to be predictive of complications.

Heart Dose Is an Independent Dosimetric Predictor of Overall Survival in Locally Advanced Non-Small Cell Lung Cancer

INTRODUCTION

In the randomized trial of standard- versus high-dose chemoradiotherapy for locally advanced (LA) NSCLC (Radiation Therapy Oncology Group 0617), overall survival (OS) was worse in the high-dose arm. Although heart dose was suggested as a contributing factor, actionable parameters have not been established. We present an analysis of clinical and dosimetric parameters affecting OS in this patient population, focusing on heart dose.

METHODS

Clinical data were collected on 416 patients with LA NSCLC treated at a single institution, with a subset of 333 available treatment plans recontoured using Radiation Therapy Oncology Group 0617 normal tissue guidelines. Toxicity and dosimetry data were analyzed for 322 patients; multivariate analysis was performed on 251 patients. Dosimetric parameters of radiation to tumor and organs at risk were analyzed with clinical data pertaining to OS, disease-free survival, and toxicity.

RESULTS

Patients were treated with radiation therapy to prescribed doses of 50.0 to 84.9 Gy (median 66.0 Gy). Median follow-up was 14.5 months. Median OS was 16.8 months. The 1- and 2-year OS rates were 61.4% and 38.8%, respectively. On multivariate analysis, factors independently associated with worse OS were increasing heart V₅₀ (volume receiving ≥50 Gy), heart volume, lung V₅ (proportion of the lung structure [excluding the target volume]) receiving at least 5 Gy), bilateral mediastinal lymph node involvement, and lack of concurrent chemotherapy. When stratified by heart V₅₀ less than 25% versus 25% or greater, the 1-year OS rates were 70.2% versus 46.8% and the 2-year OS rates were 45.9% versus 26.7% (p < 0.0001). Median heart V₅₀ was significantly higher (20.8% versus 13.9%, p < 0.0001) for patients with cardiac toxicity with a Common Terminology Criteria for Adverse Events grade of 1 or higher.

CONCLUSIONS

Heart dose is associated with OS and cardiac toxicity for patients with LA NSCLC treated with chemoradiotherapy.

Laparoscopic repair of a colonoscopic perforation

We report a case of laparoscopic repair of a diagnostic colonoscopic perforation. No other such reports were noted in the literature. The management of colonoscopic perforations has become controversial. Operative vs nonoperative treatment is continually debated. The morbidity of operative management is significant. Colostomy is often performed. Laparoscopy should allow early evaluation of operative patients and primary repair of those with minimal contamination and no residual pathology. The benefits of minimally invasive surgery, such as shortened hospitalization and rapid return to full activities, including work, were realized in our patient. Laparoscopy should be considered in the selective management of colonoscopic perforations.

Laparoscopic cholecystectomy: evolution, early results, and impact on nonsurgical gallstone therapies

Laparoscopic cholecystectomy, a surgical technique first performed in France, has gained widespread acceptance among surgeons in the United States. The abdominal cavity is inflated by carbon dioxide, a video monitor is inserted via a laparoscope placed periumbilically, and the gallbladder is freed and removed from the liver bed by using small subcostal ports for access and dissection. Intraoperative cholangiography is routinely performed, but uncertainty exists about how best to manage choledocholithiasis. Compared with traditional cholecystectomy, initial reports describing laparoscopic cholecystectomy cite shorter recovery times because no large incisions are made, thus potentially reducing the cost and morbidity of cholecystectomy. A survey of 614 early cases supports these claims, with a reported complication rate of 1.5% and quick resumption of normal activities by patients. Because of its promise for reduced morbidity, laparoscopic cholecystectomy is challenging open cholecystectomy as the therapeutic gold standard for symptomatic cholelithiasis. Thus, the standard to which the nonsurgical gallstone therapies, such as lithotripsy and contact dissolution, will be compared may shift to laparoscopic cholecystectomy. As the laparoscopic complications are similar to those of traditional cholecystectomy, such as abscesses and bile leaks, their percutaneous treatment should not change.

Yersinia pestis: correlation of ultrastructures and immunological status

Ultrastructural identification and localization of the fraction 1 "envelope" antigen in the plague bacillus Yersinia pestis were the primary objectives of this brief study. The antigenicity of extra-cellular material between the bacilli in undisturbed cultured colonies and that of the pathogen per se were measured and correlated by means of the semi quantitative complement fixation method after incubation for 72 h at 37 C. When the amount of extracellular substance in wild-type T1 (virulent) bacteria was compared by electron microscopy with that in avirulent strains of Y. pestis, with and without passage through guinea pigs, we found that the material of interest was greatly attenuated or even absent in colonies that had not been passed through animals, whereas passage markedly augmented production of the material. We also explored the requirement for larger quantities of Ca(2+) and Mg(2+) in the culture media and discovered that without these ions production of the extracellular material was limited. These observations support the hypothesis that this extracellular substance between cultured Y. pestis bacilli of various strains represents the source of the fraction 1 envelope antigen.