Q (sonnet): What percentage of genomic events in the MSK-CHORD Study occur in genes that are off-panel (not covered by the sequencing panel used)? ▶ read_guide { "uri": "cbioportal://mutation-frequency-guide" } ▶ read_guide { "uri": "cbioportal://sample-filtering-guide" } ◀ 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) ▶ get_study_guide { "study_id": "msk_chord_2024" } ◀ result # Sample and Study Filtering Guide ## Overview Proper filtering is essential for meaningful cBioPortal analysis. This guide covers filtering by studies, sample types, and other criteria. ## Study-Level Filtering ### 1. Always Filter by Study Every query should specify a study to ensure consistent results: ```sql -- Always include study filtering SELECT * FROM your_table WHERE cancer_study_identifier = 'your_study_id' -- Additional filters... ``` ### 2. Find Available Studies ```sql -- Discover available studies SELECT cancer_study_identifier, name, description, type_of_cancer_id FROM cancer_study ORDER BY cancer_study_identifier; ``` ### 3. Study Information ```sql -- Get detailed study information SELECT cs.cancer_study_identifier, cs.name as study_name, cs.description, cs.sample_count, COUNT(DISTINCT p.internal_id) as patient_count FROM cancer_study cs LEFT JOIN patient p ON cs.cancer_study_id = p.cancer_study_id WHERE cs.cancer_study_identifier = 'your_study_id' GROUP BY cs.cancer_study_identifier, cs.name, cs.description, cs.sample_count; ``` ### 4. Find Studies by Available Data Types Use this when the user asks *"which studies have mutation and copy-number data for X"*, *"studies with expression for Y"*, *"is there any imaging data"*, or any *"studies with Z data"* question. `cancer_study` has one precomputed sample count per data type — filter on them. No join and no schema exploration needed. These are the same counts as the portal's study list and its "Data type" filter. **Canonical query — studies with ALL requested data types for a cancer type:** ```sql SELECT cancer_study_identifier, name, sample_count, mutation_sample_count, cna_sample_count FROM cancer_study WHERE type_of_cancer_id = 'luad' -- ← OncoTree code from search_oncotree AND mutation_sample_count > 0 -- ← one condition per required data type AND cna_sample_count > 0 ORDER BY sample_count DESC; ``` **Data type → column** (a count of 0 means the study doesn't have that data): | Data type in the user's question | Column (portal "Data type" filter label) | |---|---| | samples in the study | `sample_count` | | mutation / mutations | `mutation_sample_count` ("Mutations") | | copy-number / CNA / amplification / deletion | `cna_sample_count` ("CNA") | | structural variant / fusion | `structural_variant_sample_count` | | RNA / mRNA / gene expression (any platform) | `mrna_expression_sample_count` — use this for "which studies have expression data" | | specifically the portal's "RNA-Seq" filter | `rna_seq_sample_count` ("RNA-Seq") — counts only the `_rna_seq_v2_mrna` list; 0 for many GDC and iAtlas studies that do have RNA-Seq | | specifically the portal's "RNA (microarray)" filter | `mrna_microarray_sample_count` ("RNA (microarray)") — counts only the `_mrna` list | | microRNA | `mirna_sample_count` ("miRNA") | | protein / RPPA | `rppa_sample_count` ("RPPA") | | mas … (7083 more chars) ◀ result # MSK-CHORD (MSK, Nature 2024) **Study ID:** `msk_chord_2024` ## Overview Targeted sequencing via MSK-IMPACT panels. Clinical annotations include some derived from natural language processing (denoted NLP). **Exactly five cancer types** (`CANCER_TYPE`, patients): Non-Small Cell Lung Cancer 7,809, Colorectal Cancer 5,543, Breast Cancer 5,368, Prostate Cancer 3,211, Pancreatic Cancer 3,109. There is **no melanoma** or any other cancer type; say so up front if asked, instead of substituting another type. **No therapy-response variable.** There is no RECIST, objective response, or best-response attribute or event. For treatment-outcome questions (e.g. immunotherapy response), say this first; the only proxies are `OS_MONTHS`/`OS_STATUS`, or NLP radiology progression events (`Diagnosis` events with `SUBTYPE = 'Progression'`, key `PROGRESSION` = Y/N/Indeterminate), in patients with `Treatment` events of the relevant `SUBTYPE` (e.g. `Immuno`: 3,341 patients). Hand off the comparison to cBioPortal group comparison / survival. **Nearly one sample per patient: 24,950 patients / 25,040 samples.** Only 90 patients have more than one sample, and all 90 have samples from two different cancer types (second primaries); only 26 have both a `Primary` and a `Metastasis` sample. There is no meaningful same-patient (paired) primary-vs-metastasis cohort. For "same patient" / paired questions, say this up front, then offer the **unpaired** comparison of all `Primary` vs `Metastasis` samples (`SAMPLE_TYPE`), labelled as unpaired. ```sql SELECT countIf(n > 1) AS multi_sample_patients, -- 90 countIf(has_p AND has_m) AS primary_and_met -- 26 FROM (SELECT patient_unique_id, count() AS n, has(groupArray(attribute_value), 'Primary') AS has_p, has(groupArray(attribute_value), 'Metastasis') AS has_m FROM clinical_data_derived WHERE cancer_study_identifier = 'msk_chord_2024' AND attribute_name = 'SAMPLE_TYPE' GROUP BY patient_unique_id); ``` ## Gene Panels This study uses multiple MSK-IMPACT panel versions: - **IMPACT341**: Earlier version, 341 genes - **IMPACT410**: 410 genes - **IMPACT468**: 468 genes - **IMPACT505**: Latest version, 505 genes **Important:** Different samples may have different gene coverage. Always use gene-specific denominators when calculating mutation frequencies. ## Clinical Attributes - Semantic Guide ### Cancer Classification | Attribute | Description | Values | |-----------|-------------|--------| | `CANCER_TYPE` | Broad cancer category | e.g., "Non-Small Cell Lung Cancer", "Breast Cancer" | | `CANCER_TYPE_DETAILED` | Specific subtype | e.g., "Lung Adenocarcinoma", "Invasive Ductal Carcinoma" | | `ONCOTREE_CODE` | OncoTree classification code | Standardized cancer type codes | ### Sample Information | Attribute | Description | Values | |-----------|-------------|--------| | `SAMPLE_TYPE` | Sample origin | Primary, Metastasis, Local Recurrence, Unknown | | `SAMPLE_CLASS` | Sample … (5439 more chars) ▶ clickhouse_list_table_columns { "table": "genomic_event_derived" } ◀ result {"columns":[{"name":"sample_unique_id","type":"String"},{"name":"hugo_gene_symbol","type":"String","comment":"HUGO gene symbol (e.g., TP53, KRAS, BRAF). Use for gene-specific queries."},{"name":"entrez_gene_id","type":"Int32"},{"name":"gene_panel_stable_id","type":"LowCardinality(String)"},{"name":"cancer_study_identifier","type":"LowCardinality(String)"},{"name":"genetic_profile_stable_id","type":"LowCardinality(String)"},{"name":"variant_type","type":"LowCardinality(String)","comment":"Type of genomic event: \"mutation\" for SNVs/indels, \"cna\" for copy number alterations, \"structural_variant\" for SVs. Always filter by this."},{"name":"mutation_variant","type":"String","comment":"Protein change notation (e.g., p.V600E, p.R175H). Use for specific variant queries. \"NA\" for non-mutation events."},{"name":"mutation_type","type":"LowCardinality(String)"},{"name":"mutation_status","type":"LowCardinality(String)","comment":"For mutations: Somatic, Germline, UNKNOWN, or UNCALLED. Filter mutation_status != \"UNCALLED\" to exclude uncertain calls. Include all other statuses."},{"name":"driver_filter","type":"LowCardinality(String)"},{"name":"driver_filter_annotation","type":"String"},{"name":"driver_tiers_filter","type":"LowCardinality(String)"},{"name":"driver_tiers_filter_annotation","type":"String"},{"name":"cna_alteration","type":"Nullable(Int8)","comment":"Copy number alteration: only 2 = amplification (AMP) and -2 = deep deletion (HOMDEL) are stored. Shallow deletion (-1), diploid (0) and gain (1) are not in this table; query genetic_alteration_derived WHERE profile_type = 'gistic' (alteration_value is a String, e.g. '-1'). NULL for non-CNA events."},{"name":"cna_cytoband","type":"String"},{"name":"sv_event_info","type":"String"},{"name":"patient_unique_id","type":"String"},{"name":"off_panel","type":"Bool","comment":"Boolean: 1 = mutation outside gene panel coverage (off-panel), 0 = within panel (on-panel). Filter off_panel = 0 for reliable frequency calculations."}]} ▶ clickhouse_run_select_query { "query": " SELECT variant_type, off_panel, count() AS n FROM genomic_event_derived WHERE cancer_study_identifier = 'msk_chord_2024' GROUP BY variant_type, off_panel ORDER BY variant_type, off_panel " } ◀ result {"rows":[{"variant_type":"cna","off_panel":false,"n":60787},{"variant_type":"mutation","off_panel":false,"n":208082},{"variant_type":"mutation","off_panel":true,"n":150},{"variant_type":"structural_variant","off_panel":false,"n":7544},{"variant_type":"structural_variant","off_panel":true,"n":2727}]} ▶ clickhouse_run_select_query { "query": " SELECT variant_type, off_panel, mutation_status, count() AS n FROM genomic_event_derived WHERE cancer_study_identifier = 'msk_chord_2024' AND variant_type = 'mutation' GROUP BY variant_type, off_panel, mutation_status ORDER BY off_panel, mutation_status " } ◀ result {"rows":[{"variant_type":"mutation","off_panel":false,"mutation_status":"SOMATIC","n":206278},{"variant_type":"mutation","off_panel":false,"mutation_status":"UNKNOWN","n":1804},{"variant_type":"mutation","off_panel":true,"mutation_status":"SOMATIC","n":148},{"variant_type":"mutation","off_panel":true,"mutation_status":"UNKNOWN","n":2}]} ▶ clickhouse_run_select_query { "query": " SELECT countIf(off_panel = true) AS off_panel_events, count() AS total_events, round(off_panel_events * 100.0 / total_events, 3) AS pct_off_panel FROM genomic_event_derived WHERE cancer_study_identifier = 'msk_chord_2024' " } ◀ result {"rows":[{"off_panel_events":2877,"total_events":279290,"pct_off_panel":1.03}]} ▶ clickhouse_run_select_query { "query": " SELECT variant_type, countIf(off_panel = true) AS off_panel_events, count() AS total_events, round(off_panel_events * 100.0 / total_events, 2) AS pct_off_panel FROM genomic_event_derived WHERE cancer_study_identifier = 'msk_chord_2024' GROUP BY variant_type ORDER BY total_events DESC " } ◀ result {"rows":[{"variant_type":"mutation","off_panel_events":150,"total_events":208232,"pct_off_panel":0.07},{"variant_type":"cna","off_panel_events":0,"total_events":60787,"pct_off_panel":0},{"variant_type":"structural_variant","off_panel_events":2727,"total_events":10271,"pct_off_panel":26.55}]} ▶ clickhouse_run_select_query { "query": " SELECT hugo_gene_symbol, variant_type, count() AS off_panel_events FROM genomic_event_derived WHERE cancer_study_identifier = 'msk_chord_2024' AND off_panel = true GROUP BY hugo_gene_symbol, variant_type ORDER BY off_panel_events DESC LIMIT 10 " } ◀ result {"rows":[{"hugo_gene_symbol":"EML4","variant_type":"structural_variant","off_panel_events":211},{"hugo_gene_symbol":"RTEL1-TNFRSF6B","variant_type":"mutation","off_panel_events":137},{"hugo_gene_symbol":"KIF5B","variant_type":"structural_variant","off_panel_events":91},{"hugo_gene_symbol":"CD74","variant_type":"structural_variant","off_panel_events":75},{"hugo_gene_symbol":"PTPRK","variant_type":"structural_variant","off_panel_events":33},{"hugo_gene_symbol":"RSPO3","variant_type":"structural_variant","off_panel_events":32},{"hugo_gene_symbol":"EWSR1","variant_type":"structural_variant","off_panel_events":29},{"hugo_gene_symbol":"TFG","variant_type":"structural_variant","off_panel_events":26},{"hugo_gene_symbol":"ADGRG7","variant_type":"structural_variant","off_panel_events":26},{"hugo_gene_symbol":"CCDC6","variant_type":"structural_variant","off_panel_events":24}]} ▶ resolve_and_route { "studyIds": [ "msk_chord_2024" ] } ◀ result {"success":true,"message":"Found 1 study. Use the metadata to call the appropriate navigation tool(s).","data":{"totalCount":1,"studiesWithMetadata":[{"studyId":"msk_chord_2024","name":"MSK-CHORD (MSK, Nature 2024)","sampleCount":25040,"studyViewUrl":"https://www.cbioportal.org/study?id=msk_chord_2024","metadata":{"clinicalAttributeIds":["ADRENAL_GLANDS","BONE","CANCER_TYPE","CANCER_TYPE_DETAILED","CLINICAL_GROUP","CLINICAL_SUMMARY","CNS_BRAIN","CURRENT_AGE_DEID","DIAGNOSIS_DESCRIPTION","ETHNICITY","FRACTION_GENOME_ALTERED","GENDER","GENE_PANEL","GLEASON_FIRST_REPORTED","GLEASON_HIGHEST_REPORTED","GLEASON_SAMPLE_LEVEL","HER2","HISTORY_OF_PDL1","HR","ICD_O_HISTOLOGY_DESCRIPTION","INTRA_ABDOMINAL","LIVER","LUNG","LYMPH_NODES","METASTATIC_SITE","MSI_COMMENT","MSI_SCORE","MSI_TYPE","MUTATION_COUNT","NUM_ICDO_DX","ONCOTREE_CODE","OS_MONTHS","OS_STATUS","OTHER","PATHOLOGICAL_GROUP","PDL1_POSITIVE","PLEURA","PRIMARY_SITE","PRIOR_MED_TO_MSK","RACE","REPRODUCTIVE_ORGANS","SAMPLE_CLASS","SAMPLE_COUNT","SAMPLE_COVERAGE","SAMPLE_TYPE","SMOKING_PREDICTIONS_3_CLASSES","SOMATIC_STATUS","STAGE_HIGHEST_RECORDED","TMB_NONSYNONYMOUS","TUMOR_PURITY"],"molecularProfileIds":["msk_chord_2024_cna","msk_chord_2024_mutations","msk_chord_2024_structural_variants"],"availableComparisonTabs":["overlap","clinical","survival","alterations","mutations"]}}]}} ▶ navigate_to_study_view { "studyIds": [ "msk_chord_2024" ] } ◀ result {"success":true,"message":"Navigating to https://www.cbioportal.org/study/summary?id=msk_chord_2024","url":"https://www.cbioportal.org/study/summary?id=msk_chord_2024","data":{"studyIds":["msk_chord_2024"],"studies":[{"studyId":"msk_chord_2024","name":"MSK-CHORD (MSK, Nature 2024)","sampleCount":25040}],"tab":"summary","hasFilters":false,"hasPlotsConfig":false,"pageDescription":"Overview of all study data displayed as interactive charts summarizing available clinical and genomic data. Click within a chart to filter. Additional charts may be available in the Charts menu."}} ═ answer (success) **[View MSK-CHORD Study Overview](https://www.cbioportal.org/study/summary?id=msk_chord_2024)** 25,040 samples across five cancer types (NSCLC, colorectal, breast, prostate, pancreatic). Note that "off-panel" flagging is per-sample (based on which of the four IMPACT panel versions — 341/410/468/505 genes — profiled that sample), not a single fixed gene list for the whole cohort.