Q (sonnet): What are the top 5 most frequently altered genes in a structural variant in the Osteosarcoma study from TARGET?

▶ list_guides
{}

▶ list_studies
{
 "search": "Osteosarcoma TARGET"
}

◀ result
{"result":[{"uri":"cbioportal://mutation-frequency-guide","description":"Comprehensive guide for calculating gene mutation frequencies with gene-specific profiling denominators"},{"uri":"cbioportal://clinical-data-guide","description":"Guide for querying clinical data including patient vs sample level considerations"},{"uri":"cbioportal://sample-filtering-guide","description":"Guide for filtering samples and studies in cBioPortal queries"},{"uri":"cbioportal://common-pitfalls","description":"Guide to avoid common mistakes when querying cBioPortal data. If you already know which numbered pitfall applies, fetch just that section via read_guide(\"cbioportal://common-pitfalls#<number>\") (e.g. #16) instead of the full guide"},{"uri":"cbioportal://treatment-guide","description":"Guide for querying treatment/clinical event data including drug agents, timelines, and linking to genomic data"},{"uri":"cbioportal://faq-guide","description":"General cBioPortal FAQ: history, how to cite, data types, reference genome, abbreviations, GISTIC thresholds, API access"},{"uri":"cbioportal://statistical-tests-guide","description":"Statistical test selection guide — decision matrix for choosing Fisher's exact, Wilcoxon, chi-squared, t-test, ANOVA, etc. based on data type and group count"},{"uri":"cbioportal://gene-expression-guide","description":"Gene expression / copy-number / methylation analysis. Covers genetic_alteration_derived, profile_type discovery, and the gene_pair_coexpression view for Spearman correlation between two genes"},{"uri":"cbioportal://external-resources-guide","description":"Guide for finding external linked resources such as imaging, pathology, Minerva, HTAN, or other resource_* table links before declaring data unavailable"},{"uri":"cbioportal://gene-resolution-guide","description":"Guide for resolving ambiguous gene symbols, aliases, gene families, and shorthand such as CD3 before querying expression or alteration data"},{"uri":"cbioportal://study-resolution-guide","description":"Guide for resolving requested studies, avoiding silent substitute cohorts, and redirecting to known external cBioPortal instances when data is not in this deployment"},{"uri":"cbioportal://germline-guide","description":"Guide for querying germline variant data — storage columns, study discovery, query patterns, and somatic vs germline considerations"},{"uri":"cbioportal://study-guide/{study_id}","description":"Dynamic study-specific guide - use get_study_guide(study_id) tool to generate"}]}

◀ result
{"result":[{"cancer_study_identifier":"os_target_gdc","name":"Osteosarcoma (TARGET GDC, 2025)","type_of_cancer_id":"os","sample_count":159,"has_guide":true,"url":"https://www.cbioportal.org/study/summary?id=os_target_gdc"}]}

▶ read_guide
{
 "uri": "cbioportal://mutation-frequency-guide"
}

▶ get_study_guide
{
 "study_id": "os_target_gdc"
}

◀ result
# Mutation Frequency Analysis Guide

## IMPORTANT: Reporting Mutation Frequencies
- **ALWAYS report frequencies as percentages**, not raw counts: `frequency = (altered_samples / total_profiled_samples) × 100`
- For quick frequency lookups, **prefer the TCGA Pan-Cancer Atlas study first**, then offer to expand to other studies
- When reporting across multiple studies, show **ranges** (e.g., "TP53 is mutated in 30–60% of samples") rather than a single average
- **NEVER** sum mutation events across studies to compute an aggregate frequency — this can exceed 100% due to double-counting
- Warn users that samples may overlap across cohorts (e.g., MSK studies may share patients)
- **Choose and state the counting unit**: use patient-level frequencies for prevalence/rate questions unless the user explicitly asks for samples; use sample-level frequencies when the user asks about samples.
- **For "across cancer types" questions**, jump to the [Cross-Cancer-Type Mutation Frequency](#cross-cancer-type-mutation-frequency) section below — there is one correct recipe and several common wrong ones.

## Counting Unit: Samples vs Patients

Before answering any mutation count or frequency question, decide whether the unit is samples or patients and state that choice in the answer.

| User wording | Counting unit |
|--------------|---------------|
| "prevalence", "rate", "fraction of patients", "patients with", "how common is" | Patient-level: `COUNT(DISTINCT patient_unique_id)` |
| "samples", "specimens", "biopsies", sample-level cohort composition | Sample-level: `COUNT(DISTINCT sample_unique_id)` |
| Ambiguous | Ask, or default to patient-level for prevalence/rate language and say so |

### Cross-study sample-count caveat

When an answer touches more than one study and reports a sample count, prepend a one-line caveat:

> Sample IDs are unique within cBioPortal study prefixes, not guaranteed biological-sample identifiers across studies; overlapping cohorts can count the same patient/sample more than once.

Prefer one of these safer approaches:

- Use a shipped `cancer_study_query_preferences` cohort such as `pan_cancer_tcga` or `all_studies_non_redundant`.
- Restrict to one named study.
- Aggregate by `patient_unique_id` when the biological question is patient prevalence.

## STOP rule: a frequency above 100% means your query is wrong

If your query returns a frequency over 100%, **do not try to debug or explain the data inconsistency to the user**. The cause is always one of these query bugs:

- Summing mutation events instead of `COUNT(DISTINCT sample_unique_id)` for the numerator
- Using a study-wide sample count as the denominator instead of the gene-specific profiled count
- Cross-study aggregation where the same biological sample appears under multiple `sample_unique_id` values (e.g., MSK-IMPACT and MSK-CHORD share patients)
- **Joining the profiled CTE through `gene_panel` / `gene_panel_list` without a WES branch.** `gene_panel_id = 'WES'` is *not* a row in … (35166 more chars)

◀ result
# Osteosarcoma (TARGET GDC, 2025)

**Study ID:** `os_target_gdc`

## Overview
Pediatric osteosarcoma study from the TARGET (Therapeutically Applicable Research to Generate Effective Treatments) initiative. Whole exome sequencing data.

## Gene Panel
- **WES** (Whole Exome Sequencing): all coding genes profiled
- **143 of the 160 samples are profiled for mutations.** Use 143 as the mutation-frequency denominator (`sample_to_gene_panel_derived`, `alteration_type = 'MUTATION_EXTENDED'`), not the study's sample count — e.g. TP53 is mutated in 32/143 = 22.4%.

## Patients vs Samples
383 patients have clinical data, but only 153 of them have a sample (159 samples). Patient-level questions (age, sex, survival) use all patients with a value; genomic questions use the 143 mutation-profiled samples.

## Clinical Attributes - Semantic Guide

### Patient Demographics
| Attribute | Description | Notes |
|-----------|-------------|-------|
| `AGE` | Age at diagnosis, **floored at 18** | Every patient younger than 18 is recorded as 18 (241 of 293). **Don't use it for age statistics** — use `DAYS_TO_BIRTH` |
| `DAYS_TO_BIRTH` | Days from birth to diagnosis, negative | Age at diagnosis in years = `-DAYS_TO_BIRTH / 365.25`. 293 patients have a value; 90 are empty |
| `SEX` | Patient sex | Male 172, Female 133, 78 empty |
| `RACE`, `ETHNICITY` | Race, ethnicity | |

### Disease Characteristics
| Attribute | Description | Notes |
|-----------|-------------|-------|
| `CANCER_TYPE_DETAILED` | Cancer type | Osteosarcoma for every sample |
| `PRIMARY_SITE_PATIENT` | Primary site | "Appendicular Skeleton" for every patient with a value — no finer location (femur, tibia) |

No histological subtype, tumor necrosis / chemotherapy response, or event-free survival attributes exist in this study.

### Clinical Outcomes
| Attribute | Description | Notes |
|-----------|-------------|-------|
| `OS_MONTHS` | Overall survival in months | Time from diagnosis |
| `OS_STATUS` | Overall survival status | 0:LIVING 171, 1:DECEASED 105, 107 empty |

## Age at Diagnosis

Compute age from `DAYS_TO_BIRTH`, not `AGE`. A median from `AGE` comes out as 18 because every child is recorded as 18; the real median is about 15 years.

```sql
SELECT
    count() AS patients,
    round(median(-toFloat64OrNull(attribute_value) / 365.25), 1) AS median_age_years,
    round(min(-toFloat64OrNull(attribute_value) / 365.25), 1) AS min_age_years,
    round(max(-toFloat64OrNull(attribute_value) / 365.25), 1) AS max_age_years
FROM clinical_data_derived
WHERE cancer_study_identifier = 'os_target_gdc'
  AND attribute_name = 'DAYS_TO_BIRTH'
  AND toFloat64OrNull(attribute_value) IS NOT NULL;
-- 293 patients, median 15.2, range 3.6-87.1
```

When reporting, say the age comes from `DAYS_TO_BIRTH` and that `AGE` is floored at 18.

## Notes & Caveats
- This is a pediatric cancer cohort; age distribution is younger than adult studies
- WES coverage means no gene panel filtering needed for frequency calculations
- Part  … (66 more chars)

▶ clickhouse_run_select_query
{
 "query": "SELECT * FROM top_sv_genes_in_study(study = 'os_target_gdc', top_n = 5)"
}

◀ result
{"rows":[]}

▶ clickhouse_run_select_query
{
 "query": "SELECT DISTINCT variant_type FROM genomic_event_derived WHERE cancer_study_identifier = 'os_target_gdc'"
}

◀ result
{"rows":[{"variant_type":"cna"},{"variant_type":"mutation"}]}

▶ clickhouse_run_select_query
{
 "query": "SELECT genetic_profile_id, genetic_alteration_type, datatype, name FROM genetic_profile WHERE cancer_study_identifier = 'os_target_gdc'"
}

◀ result
{"error_message":"Query execution failed: HTTPDriver for https://dl96orhu96.us-east-1.aws.clickhouse.cloud:8443 received ClickHouse error code 47\n Code: 47. DB::Exception: Unknown expression or function identifier `cancer_study_identifier` in scope SELECT genetic_profile_id, genetic_alteration_type, datatype, name FROM genetic_profile WHERE cancer_study_identifier = 'os_target_gdc'. (UNKNOWN_IDENTIFIER) (version 26.4.1.2359 (official build))\n"}

▶ resolve_and_route
{
 "studyIds": [
  "os_target_gdc"
 ]
}

◀ result
{"success":true,"message":"Found 1 study. Use the metadata to call the appropriate navigation tool(s).","data":{"totalCount":1,"studiesWithMetadata":[{"studyId":"os_target_gdc","name":"Osteosarcoma (TARGET GDC, 2025)","sampleCount":159,"studyViewUrl":"https://www.cbioportal.org/study?id=os_target_gdc","metadata":{"clinicalAttributeIds":["AGE","CANCER_TYPE","CANCER_TYPE_DETAILED","DAYS_TO_BIRTH","DAYS_TO_DEATH","DISEASE_TYPE","ETHNICITY","MUTATION_COUNT","ONCOTREE_CODE","OS_MONTHS","OS_STATUS","PRIMARY_DIAGNOSIS","PRIMARY_SITE_PATIENT","PROJECT_ID","RACE","SAMPLE_COUNT","SEX","SPECIMEN_TYPE","TMB_NONSYNONYMOUS","VITAL_STATUS"],"molecularProfileIds":["os_target_gdc_cna","os_target_gdc_mrna_seq_fpkm","os_target_gdc_mrna_seq_fpkm_Zscores","os_target_gdc_mrna_seq_read_counts_Zscores","os_target_gdc_mrna_seq_tpm","os_target_gdc_mrna_seq_tpm_Zscores","os_target_gdc_mutations","os_target_gdc_rna_seq_mrna"],"heatmapProfileIds":["os_target_gdc_mrna_seq_fpkm_Zscores","os_target_gdc_mrna_seq_read_counts_Zscores","os_target_gdc_mrna_seq_tpm_Zscores"],"availableComparisonTabs":["overlap","clinical","survival","alterations","mutations","mrna"]}}]}}

═ answer (success)
This confirms the finding: the study's molecular profiles are `cna`, `mutations`, and several `mrna_seq` expression profiles — **no structural variant profile exists**.

## Answer

The **Osteosarcoma (TARGET GDC, 2025)** study (`os_target_gdc`, 159 samples) does not include a structural variant (fusion) molecular profile in cBioPortal. Available data types are limited to:
- Mutations (`os_target_gdc_mutations`)
- Copy-number alterations (`os_target_gdc_cna`)
- mRNA expression (FPKM/TPM, Z-scores)

There is no SV data to compute "top 5 most frequently altered genes by structural variant" for this cohort.

If useful, I can instead provide the top 5 most-mutated genes or top 5 CNA genes for this study — let me know which you'd like.

[View Osteosarcoma (TARGET GDC, 2025) Study View](https://www.cbioportal.org/study?id=os_target_gdc)