Surgical management of truncal soft tissue sarcoma and other selected soft tissue neoplasms

Soft tissue sarcoma (STS) is a heterogeneous entity comprising only 1% of all adult cancers that has received considerable attention since it was initially described after the 1st century as "fleshy" by Claudius Galenus. Nick-named the forgotten cancer, more than 100 histologic subtypes have been identified making treatment paradigms extremely complex. A key principle in the management of truncal STS is a defined multi-disciplinary team consisting of several providers. In most instances, surgery is the cornerstone of treatment. This overview will focus on the management of truncal sarcoma from a surgical perspective that will entail several points of consideration including histologic subtype, degree of differentiation, margin status as well as necessity of reconstruction; it will also include discussion of other unique soft tissue neoplasms relevant to the breast and abdominal wall.

Abstract B23: Targeted exome sequencing for effectors involving the MAPK and PI3K pathways of cutaneous melanoma in the minority population: Identifying unique molecular signatures

Background: Melanoma is a global problem, as its incidence is rising faster than any other malignancy for both men and women. Since Caucasians are primarily affected by melanoma, most of the clinical effort and patient education is focused on this cohort. In minorities, melanoma is usually detected at a more advanced stage, distributed on sun-protected areas and associated with a worse survival. Previous studies have depicted the relevance of alterations in the MAPK and PI3K pathways; however, inclusion of a multi-ethnic population comprising of unique groups such as Native Hawaiians, Pacific Islanders, Filipinos, and other Asians has been limited.

Methods: IRB approval was obtained for this retrospective analysis. From 2008 to 2013, 10 Asian/Pacific Islander patients histologically confirmed to have invasive conventional (non-acral) cutaneous melanoma were evaluated at a tertiary institution. Data including age, gender, tumor location, Breslow thickness, ulceration, and mitoses per mm squared were compiled. Using a cloud based in silica primer design software target genes was chosen. Multiplex primers were generated. Coverage was assessed using the University of California, Santa Cruz (UCSC) and National Center for Biotechnology Information (NCBI) genome browsers to ensure that known pathogenic single nucleotide polymorphisms were captured from the latest dbSNP genome build. Targets included AKT, BRAF, C-KIT, MEK, MTOR, NRAS, and PI3K. This pre-designed multiplexed panel contains genes across families representing driver mutations in signaling pathways. Next generation sequencing was performed using the Ion Torrent Personal Genome Machine™.

Results: Our findings demonstrated a unique molecular distribution. Interestingly in our non-Caucasian cohort of conventional melanoma, PI3K mutations were found in 30% (normally 2-6% in Caucasians) of the biospecimens, which supports our hypothesis that ethnic minorities may have a distinct biological profile. Furthermore, 40% of this minority cohort had a c-KIT mutation which is atypical for non-acral melanoma; in addition 2 of these c-KIT mutations were novel and not classically associated with melanoma in Caucasians. What is also compelling is that 50% had simultaneous mutations, including 30% that had a concomitant PI3K mutation. Demographics of the multi-ethnic cohort included mean age of 57.5 years (range 19-80) and male gender (4/10; 40 %). Tumor location primarily involved the extremity (8/10; 80%); median Breslow thickness was 1.97 mm (range 0.77-16.0), and mean mitoses per mm squared was 5.2 (range 0-16).

Conclusion: This is compelling data that may be applied to patient selection in future trials utilizing targeted agents and assist with gleaning insight into the mechanism of melanoma genesis. Molecular profiling diverse cohorts may improve the identification of novel molecular signatures germane to melanoma biology and therapy.

Note: This abstract was not presented at the conference.

Citation Format: Shane Y. Morita. Targeted exome sequencing for effectors involving the MAPK and PI3K pathways of cutaneous melanoma in the minority population: Identifying unique molecular signatures. [abstract]. In: Proceedings of the Seventh AACR Conference on The Science of Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; Nov 9-12, 2014; San Antonio, TX. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2015;24(10 Suppl):Abstract nr B23.

Rare presentations of primary melanoma and special populations: a systematic review

A subset of patients with melanoma present in rare and unique clinical circumstances requiring specific considerations with respect to diagnostic and therapeutic interventions. Herein, we present our review of patients with: (1) primary mucosal melanoma of the head and neck, gastrointestinal, and genitourinary tracts; (2) primary melanoma of the eye; (3) desmoplastic melanoma; (4) subungual melanoma; (5) melanoma in special populations: children, nonwhites, as well as a discussion of familial melanoma.

Abstract A80: Acral melanoma in the Hawaiian Islands: Exploring immunologic PDL-1 signature in the minority population

Background: While acral melanoma (AM) is the least common subtype amongst the principal histologic variants of cutaneous melanoma (CM), darker-skinned individuals such as Asians, Pacific Islanders, and African Americans are more frequently affected. Asian/Pacific Islanders with AM in particular, exhibit the worst survival amongst all ethnic groups. Recent studies have profiled the importance of programmed cell death ligand 1 (PDL-1) in the therapeutic armamentarium for melanoma. However, the pathologic features and immunologic characteristics of AM evaluating PDL-1 in the minority population have not been thoroughly analyzed.

Methods: IRB approval was obtained for this retrospective analysis. From 2004 to 2011, 17 Asian/Pacific Islander patients histologically confirmed to have invasive AM were evaluated at a tertiary institution. Data including age, gender, tumor location, Breslow thickness, ulceration, tumor infiltration lymphocyte (TIL) status, and mitoses per mm squared were compiled. Immunohistochemistry was performed targeting the PDL-1 (CD274) antigen on primary tumor cells in formalin-fixed paraffin-embedded archived biospecimens. PDL-1 expression was graded on a scale from 0 (absent) to 2 (high).

Results: Our findings demonstrated that PDL-1 expression was low in this series (3/17; 17.6%). All AM patients had a non-brisk TIL response. A significant proportion of our entire cohort (8/17; 47.1%) exhibited thick primary lesions (>4.0 mm) with a high propensity for ulceration (8/17; 47.1%). Demographics of the Asian/Pacific Islander cohort included mean age of 63.8 years (range 40-86) and male gender (9/17; 53 %). Tumor location primarily involved the foot (11/17; 64.7%); median Breslow thickness was 3.98 mm (range 0.96-11.0), and mean mitoses per mm squared was 3.9 (range 0-10). Conclusion: Asian/Pacific Islanders with AM were found to have a low frequency of PDL-1 expression. The lack of a brisk lymphocytic host response in AM may provide insight into its mechanism of tumorigenesis. This is the first study to our knowledge that has examined the immunologic signature of TIL and PDL-1 status in a multi-ethnic population of AM patients. This is compelling data that may be applied to patient selection in future trials utilizing immunotherapy.

Citation Format: Shane Y. Morita. Acral melanoma in the Hawaiian Islands: Exploring immunologic PDL-1 signature in the minority population. [abstract]. In: Proceedings of the Sixth AACR Conference: The Science of Cancer Health Disparities; Dec 6–9, 2013; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2014;23(11 Suppl):Abstract nr A80. doi:10.1158/1538-7755.DISP13-A80

Molecular targets in melanoma: time for 'ethnic personalization'

Worldwide, the incidence of melanoma continues to rise. Although not the most common cutaneous malignancy, it is the most lethal. Until recently, while other oncologic patients benefited from the nuances of targeted therapy, those afflicted with melanoma lacked that option. In 2011, the US FDA approved an oral agent that targets the BRAF oncogene. As this information is promising, it is essential that other populations (in addition to Caucasians) are examined, in order to further comprehend the biology of melanoma. Recent studies profiling various ethnicities, including Asians, have provided novel data with respect to the molecular characterization (c-KIT, BRAF, NRAS) of melanoma. It is hopeful that the management of melanoma will be universally applicable to all ethnic groups.

Abstract B76: Thyroid cancer ethnic disparity in Hawaii: BRAF mutation within the Filipino population

Background: The incidence of thyroid cancer is rapidly progressing in the United States, with the vast majority attributed to papillary thyroid carcinoma (PTC). In Hawaii, Filipinos comprise the largest group affected by this malignancy. Although generally perceived to be indolent, previous investigators have noted that Filipinos with thyroid cancer have a higher recurrence rate. Interestingly, biologic factors to explicate this disparity have not been fully elucidated. The prevalence of the BRAF mutation in PTC is approximately 45% and has been associated with an aggressive phenotype as well as an adverse prognosis. However, molecular profiling for this somatic mutation within the Filipino PTC population has not been conducted. The Pacific Basin provides a unique opportunity to study diseases in distinct ethnic groups. We elected to examine the frequency of the BRAF mutation in PTC within the Filipino population here in Hawaii.

Methods: IRB approval was obtained for this retrospective analysis. From 1992–2006, 37 Filipino patients histologically confirmed to have conventional PTC were evaluated at a tertiary care medical center. Data including age, gender, tumor size, subtype, extrathyroidal extension, multifocality, lymph node involvement, presence of distant metastasis, and American Joint Committee on Cancer (AJCC) stage were compiled. Detection for the BRAF somatic mutation was performed on formalin-fixed/ paraffin-embedded archived surgical biospecimens. Tumor DNA was isolated via laser capture microdissection and ascertained by a microarray chip containing a panel of selected V600 BRAF point mutations, including A, D, E1, E2, and KRM. Comparison of the average BRAF frequency as reported in the literature versus our study cohort was done by binomial proportion analysis. Five-year survival was calculated by the Kaplan-Meier method. Fisher's exact test was used to determine if extrathyroidal extension was a predictor for the BRAF mutation.

Results: Our findings demonstrated that 31/37 (83.8%) of our patients harbored the BRAF mutation and were exclusively the V600E1 variant. This was statistically significant with a p-value of <0.001. Additionally, 5-year survival for our cohort was only 84.2%. Demographics of the Filipino population included mean age of 47 years old (range 21–87) and female gender 28/37 (76%). All patients possessed the conventional subtype of PTC; those with aggressive histologies such as tall-cell or insular were excluded. The average tumor size was 2.1 cm (range 0.4–6.0); extrathyroidal extension was 23/37 (62%), multifocality 18/37 (49%), lymph node involvement 17/37 (46%), while presence of distant metastasis was only 2/37 (5%). AJCC stage distribution was I=19/37 (51%), II=4/37 (11%), III=11/37 (30%), and IV=3/37 (8%). Eleven patients (11/14 i.e. 78.6%) did not possess extrathyroidal extension, although they were BRAF mutant. There was no association between extrathyroidal extension and BRAF mutation (p-value 0.65).

Conclusions: Filipino patients with conventional PTC were unequivocally found to have a high preponderance of the BRAF mutation (83.8%) when compared to the norm in the literature (45%). Although extrathyroidal extension has historically been documented as a predictor for BRAF mutation, we did not find this association in our study. Despite the fact that half of our cohort had stage I disease, five-year survival was lower with respect to the literature. This is the first study to our knowledge that has profiled the BRAF mutation in a Filipino population of PTC patients. This is compelling data that may be applied to the metastatic phenotype in future trials and advocates the potential utility of ethnicity as a legitimate prognostic variable. More importantly, this supports the concept of conducting ethnic disparities research in understudied populations such as the Filipinos, who have increased in number by nearly 40% in the U.S.

Citation Information: Cancer Epidemiol Biomarkers Prev 2011;20(10 Suppl):B76.

Increased Fatalities and Cost of Traumatic Injuries in Elderly Pedestrians in Hawaii: A Challenge for Prevention and Outreach

This study was carried out to evaluate and quantify risk factors, mechanisms, and cost of traumatic injuries in Hawaii's elderly and to identify potential preventive strategies. A retrospective review of a prospective database of patients admitted to the only Trauma Center in the Pacific Basin, between January 2000 and December 2001, was conducted. Of 2634 trauma admissions, 11% were ≥65 years of age. Mechanisms of injury included falls, motor vehicle crashes (MVCs), pedestrians hit by automobiles, and miscellaneous causes. The incidence of elderly pedestrians hit by automobiles in Hawaii is higher than previously reported. Hospital mortality rate was highest for the pedestrian hit group, followed by falls, and then MVCs. The pedestrian hit group consumed the largest quantity of resources and MVCs the least. Given the high mortality rate and associated resource consumption in the pedestrian hit group, it would be appropriate to give priority to this group while developing preventive measures for this age group.

Twenty-eight-day mortality in critically ill surgical patients is an imprecise temporal end-point measure for in-hospital mortality

BACKGROUND

The purpose of this study was to determine the incidence of deaths occurring beyond 28 days in critically ill surgical patients and to identify the proportion of these deaths attributable to the original disease process.

METHODS

Analysis of 1,360 subjects admitted to a surgical intensive care unit during a 2 year period. Demographics, indication(s) for admission, comorbidities, mortality rate, multiorgan failure development, and cause of death was obtained.

RESULTS

Mortality rate in the surgical intensive care unit was 12%. Twenty % of deaths occurred more than 28 days after hospital admission with 76% of deaths related to admission diagnosis. By day 34, 95% of mortalities had occurred.

CONCLUSIONS

The 28-day time period used to assess efficacy of therapeutic interventions and to define mortality in the context of quality audits should be questioned. If these findings are validated in other centers another temporal end point for in-hospital mortality should be considered.

Combining agents that target the tumor microenvironment improves the efficacy of anticancer therapy

PURPOSE

Over the past 60 years, cytotoxic chemotherapy has targeted the cancer cell. Despite this, there have been few cancer cures. A new approach to cancer therapy is to target the multicellular biological entity of the tumor microenvironment.

EXPERIMENTAL DESIGN

Lenalidomide, an immunomodulatory drug, sunitinib, a tyrosine kinase inhibitor, and low-dose metronomic cyclophosphamide, were tested alone and in combination for their abilities to inhibit endothelial cell tube formation, rat aortic ring outgrowth, tumor growth, and metastatic development in mice. In addition, ectopic tumor lysates were evaluated for the presence of proangiogenic proteins.

RESULTS

The three agents alone were shown to significantly inhibit endothelial cells' ability to form tubes and significantly inhibit the multicellular microenvironment in the rat aortic ring assay (P < 0.01 and P < 0.001). This effect was also significantly augmented when the agents were combined. Furthermore, the three-drug combination was able halt the progression of tumor growth almost completely in xenograft models of ocular melanoma, colon cancer, pancreatic cancer, and cutaneous melanoma. These agents significantly decrease the number of proliferating cells in tumors, significantly increase the number of cells undergoing active cell death in tumors, and significantly decrease the number of blood vessels in treated tumors (P < 0.05). Combination therapy shows a decrease in the compensatory up-regulation of proangiogenic proteins after treatment when compared with single-agent therapy.

CONCLUSIONS

This combination of agents causes an inhospitable microenvironment for tumor cells and shows great promise for use in the clinic.

Transcutaneous pressure of oxygen: a noninvasive and early detector of peripheral shock and outcome

A noninvasive tool to recognize early shock would improve outcome by providing prompt recognition of tissue ischemia and precise resuscitation endpoint. The skin is the first tissue bed to vasoconstrict in shock states. Studies have demonstrated that transcutaneous partial pressure of oxygen (PtCO2) increases with higher FiO2 in nonshock states as arterial pressure of oxygen (PaO2) increases, but in shock situations, PtCO2 mirrors changes in cardiac output and oxygen delivery with minimum response to increasing FiO2 and PaO2. This study examined the relationship of hemodynamic variables and the degree of PtCO2 response to FiO2 of 1.0 (identified as the "oxygen challenge test") to mortality and organ failure. This prospective observational study examined 38 patients requiring at least 24 h of cardiac output monitoring for shock resuscitation in the Surgical Intensive Care Unit. Patients were resuscitated to the standard protocol of blood pressure, urine output, oxygen delivery (DO2), and mixed venous O2 (SvO2). Seventy-nine percent of the patients (30/38) with a mean age of 59 +/- 21 years had septic shock or severe sepsis with a 26% mortality (10/38). Measurements included hemodynamic variables, PtCO2, and outcome (mortality and organ failure). In this study, the ability of PtCO2 value to increase by 21 mmHg on a FiO2 of 1.0, at 24 h of resuscitation, divided survivors from nonsurvivors, P <.001. The PtCO2 response to FiO2 may provide an additional noninvasive method of detecting early shock as well as a specific endpoint of resuscitation.

Uncompensated Metabolic Acidosis: An Underrecognized Risk Factor for Subsequent Intubation Requirement

BACKGROUND

There are no published reports identifying an inadequate ventilatory response to metabolic acidosis as a predictor of impending respiratory failure. Metabolic acidosis should induce a respiratory alkalosis in which the partial pressure of carbon dioxide (Paco2) is (1.5 [HCO3-] + 8) +/- 2. This study examined the relation between inadequate ventilatory compensation and intubation among trauma patients.

METHODS

A retrospective chart review was performed for trauma patients admitted between January 1999 and December 2000. Age, gender, Injury Severity Score and combined Trauma and Injury Severity Score, chest injury, history of cardiac or pulmonary disease, partial pressure of oxygen (Pao2), Paco2, Glasgow Coma Score, respiratory rate, systolic blood pressure, base deficit, and ability to compensate were analyzed with respect to intubation and need for ventilator support.

RESULTS

Of 140 patients with metabolic acidosis, 45 ultimately were intubated. The mean Paco2 for the unintubated patients was 34 +/- 7 mm Hg, as compared with 41 +/- 11 mm Hg for the intubated patients (p < 0.001). Only injury severity and ability to compensate for metabolic acidosis were independent predictors of intubation. Patients with inadequate compensation were 4.2 times more likely to require intubation when control was used for the Injury Severity Score (95% confidence interval, 1.8-9.7; p < 0.001).

CONCLUSIONS

Inability to mount an adequate hyperventilatory response to metabolic acidosis is associated with an increased likelihood of respiratory failure and a need for ventilatory support. Recognition of this relation should lead to closer monitoring of patients with this condition, and could help to avert unforeseen crisis intubations. This observation needs to be validated in a prospective study.

Time dependent ethnic convergence in colorectal cancer survival in Hawaii

BACKGROUND

Although colorectal cancer death rates have been declining, this trend is not consistent across all ethnic groups. Biological, environmental, behavioral and socioeconomic explanations exist, but the reason for this discrepancy remains inconclusive. We examined the hypothesis that improved cancer screening across all ethnic groups will reduce ethnic differences in colorectal cancer survival.

METHODS

Through the Hawaii Tumor Registry 16,424 patients diagnosed with colorectal cancer were identified during the years 1960-2000. Cox regression analyses were performed for each of three cohorts stratified by ethnicity (Caucasian, Japanese, Hawaiian, Filipino, and Chinese). The models included stage of diagnosis, year of diagnosis, age, and sex as predictors of survival.

RESULTS

Mortality rates improved significantly for all ethnic groups. Moreover, with the exception of Hawaiians, rates for all ethnic groups converged over time. Persistently lower survival for Hawaiians appeared linked with more cancer treatment.

CONCLUSION

Ethnic disparities in colorectal cancer mortality rates appear primarily the result of differential utilization of health care. If modern screening procedures can be provided equally to all ethnic groups, ethnic outcome differences can be virtually eliminated.

Stool appearance in intussusception: assessing the value of the term "currant jelly"

This study surveyed the stool appearance descriptions of 107 inpatient children with intussusception. Fifty-six patients presented with grossly bloody stools (passed spontaneously), 10 of which were determined on chart review to resemble currant jelly. Of the 51 patients without grossly bloody spontaneously passed stools, 35 patients had rectal examination results charted. Eight of these children had grossly bloody stools noted on rectal examination, 4 of which were determined on chart review to resemble currant jelly. While most of the grossly bloody stools were not consistent with pure currant jelly, the most common terms used in describing the grossly bloody stools were "bloody," "mucus," "red," and "diarrhea." Since stools truly resembling currant jelly account for a minority of the grossly bloody stools in intussusception, the term "currant jelly stools" should be assessed in the teaching of intussusception. Generic terms such as blood, mucus, burgundy, red, etc, are more objective and sensitive at identifying cases of intussusception. Junior physicians who are taught the classic presentation of intussusception with currant jelly stool should also be taught that intussusception should be considered in the differential diagnosis of children passing any type of bloody stool. As a result, physicians with limited experience will be more likely to appropriately consider the diagnosis of intussusception, permitting a more timely diagnosis and a better outcome.